BUILDING TECHNOLOGIES PROGRAM

BUILDERS CHALLENGE GUIDE TO

40% Whole-House Energy 

Savings in the Cold and 

Very Cold Climates

PREPARED BY

Pacific Northwest National Laboratory 

& Oak Ridge National Laboratory

February 2011

February 2011 • PNNL-20139

COLD & VERY COLD CLIMATES

VOLUME 12. BUILDING AMERICA BEST PRACTICES SERIES

R
This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the 

United States Government nor any agency thereof, nor Battelle Memorial Institute, nor any of their employees, makes any 

warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of 

any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. 

Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise 

does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any 

agency thereof, or Battelle Memorial Institute. The views and opinions of authors expressed herein do not necessarily state or 

reflect those of the United States Government or any agency thereof.
BUILDING AMERICA BEST PRACTICES SERIES

VOLUME 12.

Builders Challenge Guide to 40% 

Whole-House Energy Savings in 

the Cold and Very Cold Climates

PREPARED BY

The Building America Research Teams

Building America Industrialized Housing Partnership 

led by the Florida Solar Energy Center

Building Industry Research Alliance 

led by ConSol

Building Science Consortium 

led by Building Science Corporation

Consortium for Advanced Residential Buildings 

led by Steven Winter Associates, Inc.

Integrated Building and Construction Solutions

National Association of Home Builders Research Center

Pacific Northwest National Laboratory

Michael C. Baechler

Theresa L. Gilbride, Marye G. Hefty, and Pam C. Cole

Oak Ridge National Laboratory

Pat M. Love

February 2011

Prepared for the U.S. Department of Energy

under Contract DE-AC05-76RLO 1830

PNNL-20139
Preface

This best practices guide is the twelfth in a series of guides for builders 

produced by the U.S. Department of Energy’s Building America 

program. This guidebook is a resource to help builders design and 

construct homes that are among the most energy-efficient available, 

while addressing issues such as building durability, indoor air quality, 

and occupant health, safety, and comfort. With the measures described 

in this guide, builders in the cold and very cold climates can build 

homes that have whole-house energy savings of 40% over the Building 

America benchmark with no added overall costs for consumers. 

The best practices described in this document are based on the 

results of research and demonstration projects conducted by Building 

America’s research teams. Building America brings together the 

nation’s leading building scientists with over 300 production builders 

to develop, test, and apply innovative, energy-efficient construction 

practices. Building America builders have found they can build homes 

that meet these aggressive energy-efficiency goals at no net increased 

costs to the homeowners. To recognize builders who are producing 

the most efficient, sustainable, and comfortable homes on the market, 

DOE created the Builders Challenge. Homes that qualify for the 

Builders Challenge must achieve a 70 or lower on the EnergySmart 

Home Scale (E-Scale), which is described in this document. 

This document represents a step up from our first cold best practices 

document (Volume 3. Builders and Buyers Handbook for Improving New 

Home Efficiency, Comfort, and Durability in the Cold and Very Cold 

Climate), which aimed at achieving energy-efficiency savings of 15% 

above the benchmark, a home built to the 1993 Model Energy Code, 

the code in effect at the time of the program’s inception. Building 

America has continued to develop systematic building strategies 

that meet more challenging efficiency goals over time. The Building 

America research projects described in this guide achieve energy 

savings of 40% greater than the Building America benchmark home. 

The national energy and building codes are revised on a 3-year 

cycle. The most recent versions are the 2009 International Energy 

Conservation Code (IECC) and the 2009 International Residential 

Code (IRC). The recommendations in this document meet or exceed 

the requirements of the 2009 IECC and 2009 IRC. Beginning in fiscal 

year (FY) 2011, Building America research projects are using the 2009 

IECC as the benchmark for analysis of home energy efficiency.

Building America welcomes reader feedback on all volumes of the 

Best Practices Series. Please submit your comments via e-mail to 

George James (George.James@ee.doe.gov)

You can learn more about Building 

America and download additional copies 

of this document, other best practices, 

research reports, and case studies at 

www.buildingamerica.gov

R

The Building America recommendations 

provided in this guide meet or exceed 

the code requirements of the 2009 

International Energy Conservation Code 

(2009 IECC) and the 2009 International 

Residential Code (2009 IRC).

i Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011

BUILDING AMERICA BEST PRACTICES SERIES
Acknowledgments

The U.S. Department of Energy’s Building America program 

comprises public-private partnerships that conduct systems research 

to improve overall housing performance, increase housing durability 

and comfort, reduce energy use, and increase energy security for 

America’s homeowners. Program activities focus on finding solutions 

for both new and existing homes, as well as integrating clean onsite 

energy systems that will allow the homebuilding industry to provide 

homes that produce more energy than they use. In addition to the 

DOE management and staff, the Building America program includes 

several consortia, four DOE national laboratories, and hundreds 

of builders, research organizations, manufacturers, and service 

providers. Building America also co-manages the ENERGY STAR 

Program along with the U.S. Environmental Protection Agency, 

and works with other federal agencies to coordinate research efforts 

and disseminate findings. Together, all of these partners make the 

program a valuable source of knowledge and innovation for U.S. 

home builders. 

The DOE Building America program funded the development of 

this series of handbooks. DOE also funded the Building America 

consortia and national laboratories to conduct the research that 

forms the basis of these best practices. The consortia that conducted 

the research described in this report are listed to the right. These 

were the Building America research teams through fiscal year 2010. 

The consortia have taken on the hard work of applied research, 

field testing, training builders, and transforming results into best 

practices. Most of the drawings, descriptions, photos, and case 

studies in these guides originated with these research partners. 

Hundreds of builders across the country have chosen to work with 

Building America and its partners on research projects to further 

our understanding of building science. These builders deserve 

thankful recognition for their dedication to continually improving 

the quality and energy efficiency of the homes they build and for 

their contributions to our understanding of how buildings work. 

Five builders from the cold climate are showcased in case studies 

in this document: Devoted Builders of Kennewick, Washington; 

East Liberty Development, Inc., and S&A Homes of Pittsburgh, 

Pennsylvania; Nelson Construction of Farmington, Connecticut; 

Rural Development, Inc., of Turners Falls, Massachusetts; and 

Shaw Construction of Grand Junction, Colorado, and the City 

of Aspen, Colorado. Examples from these and other cold climate 

builders are used throughout the document to illustrate construction 

best practices. 

FY2010 Building America 

Research Teams

These Building America research teams partner 

with all segments of the building industry to 

conduct research and demonstration projects 

that develop, analyze, and test strategies 

and technologies for improving building 

performance and energy efficiency. Building 

America teams who participated in the 

preparation of this document included

Building America Industrialized 

Housing Partnership 

led by the Florida Solar Energy Center

www.baihp.org

Building Industry Research Alliance 

led by ConSol www.bira.ws

Building Science Consortium 

led by Building Science Corporation

www.buildingscienceconsulting.com

Consortium for Advanced 

Residential Buildings 

led by Steven Winter Associates, Inc.

www.carb-swa.com/index.html

Integrated Building and 

Construction Solutions

www.ibacos.com

National Association of Home 

Builders Research Center 

www.nahbrc.com

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 ii

ii

BUILDING AMERICA BEST PRACTICES SERIES
Several national laboratories participated in this project. Pacific 

Northwest National Laboratory and Oak Ridge National Laboratory 

led the writing and production of this document. The National 

Renewable Energy Laboratory made its library of Building America 

documents available to the authors, reviewed this guide, and posted 

it to the Web. Scientists at Lawrence Berkeley National Laboratory 

reviewed the document as well.

The authors and DOE wish to thank the many contributors who 

have made this project a success. We would especially like to thank 

graphic artist Christina Van Vleck who designed this document and 

prepared many of its illustrations.

iii Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011

BUILDING AMERICA BEST PRACTICES SERIES
Contents

Chapter 1. Welcome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1

Chapter 2. The Business Case for Building High-Performance Homes . . . 2.1

Builders and Building America . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1

The Business Case for Energy Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2

Consumer Preferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3

Competitive Advantage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4

Cost Neutral Energy Savings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4

Codes as Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9

Chapter 3. Business Management Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1

Quality Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1

Integrated Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4

Traditional Design Processes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5

Integrated Design Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.6

Value Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.9

Managing Innovation with Prototypes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.10

Chapter 4. Selling Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1

Branding and Labeling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1

Training Sales Staff. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3

Marketing Energy Efficiency. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5

Reach Out to the Media. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6

Chapter 5. The Cold and Very Cold Climates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1

Design Considerations for Cold Climates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2

Climate Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2

Cold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2

Very Cold. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2 

Subarctic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3

Weather . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5

Precipitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5

Flooding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5

Stormwater Management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.7 

Tornadoes and High Winds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.7 

Seismic Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.8

Forest Fires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.9

Considering Solar Gain in Siting & Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.10

Lot Orientation and Home Siting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.10

Overhangs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.12

Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.12

Shading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.13

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 iv

iv

BUILDING AMERICA BEST PRACTICES SERIES
Chapter 6. Building Science and the Systems Approach . . . . . . . . . . . . . . . . 6.1

The Systems Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1

Building Science Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1

Water. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

Vapor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

Air Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5

Heat Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6

Occupants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.9

Chapter 7. The Overall Building Envelope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1

Advanced Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1

Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4

Air Sealing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.8

The Thermal Bypass Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.11

Chapter 8. Building Envelope Sub-Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.1

Foundation Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.1

Controlling Liquid Water in Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.1

Frost Heave and Adfreeze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.3

Controlling Water Vapor in Foundations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4

Controlling Air Infiltration in Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.7

Controlling Heat Flow in Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.7

Basement Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.10

Controlling Other Foundation Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.12

Wall Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.14

Controlling Liquid Water in Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.14

Controlling Water Vapor in Walls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.17

Controlling Air Infiltration in Wall Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.19

Controlling Heat Flow in Wall Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.23

Roof Assemblies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.24

Controlling Liquid Water in Roof Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.24

Ice Dam Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.24

Controlling Water Vapor in Roof Assemblies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.26

Controlling Air Flow in Roof/Attic Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.26

Controlling Heat Flow in Roof Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.27

Window and Door Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.29

Chapter 9. Mechanical, Plumbing and Electrical Systems . . . . . . . . . . . . . . . 9.1

Heating, Ventilation and Air Conditioning (HVAC). . . . . . . . . . . . . . . . . . . . . . . . . 9.1

Heating and Cooling Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2

Ducts and Air Handlers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.7

Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.12

Plumbing and Water Heating. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.17

Hot Water Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.18

Hot Water Circulation Pumps and Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.18

Water Heaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.19

High-Performance Lighting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.23

Appliances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.25

EnergyGuide Label . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.25

ENERGY STAR Label . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.25

v Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011

BUILDING AMERICA BEST PRACTICES SERIES
Chapter 10. Occupant Health and Safety. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.1

Chapter 11. Inspecting, Testing, and Commissioning . . . . . . . . . . . . . . . . . . . . 11.1

Walkthroughs During Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1

Building Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2

Pre-Dry Wall Inspection and Duct Pressure Testing . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2

Whole-House Pressure Testing and HERS Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2

SnapShot Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.3

Homeowner Education . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.3

Chapter 12. Construction Site Documents, Scheduling, and Training . . . 12.1

Construction and Contract Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1

Contract Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.2

Scheduling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.3

Training Installers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.5

Training Tips from Cold Climate Builders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.5

Training Opportunities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.6

HotSpot Inspections and Training . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.7

Chapter 13. Durability and Energy Efficiency Checklist . . . . . . . . . . . . . . . . . 13.1

Foundation Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.1

Controlling Moisture in All Foundation Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.1

Controlling Moisture in Crawlspace and Basement Foundations . . . . . . . . . . . . . . 13.2

Controlling Air Infiltration in All Foundation Types . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.2

Controlling Heat Flow in Slab Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.2

Controlling Heat Flow in Crawlspace Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.3

Controlling Heat Flow in Basement Foundations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.3

Other Foundation Issues. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.3

Wall Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.4

Controlling Liquid Water in Wall Assemblies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.4

Controlling Water Vapor in Wall Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.5

Controlling Air Infiltration in Wall Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.5

Controlling Heat Flow in Wall Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.6

Roof Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.6

Controlling Liquid Water in Roof Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.6

Controlling Water Vapor in Roof Assemblies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.6

Controlling Air Flow in Roof Assemblies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.6

Controlling Heat Flow in Roof Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.7

Whole-House Air Leakage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.7

Mechanical Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.8

Heating and Cooling Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.8

Ducts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.8

Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.9

Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.10

Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.10

Occupant Health and Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.11

Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.11

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 vi

vi

BUILDING AMERICA BEST PRACTICES SERIES
Chapter 14. Field Guides for Installers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.1

Advanced Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.3

Foundation System, Insulation, Moisture and Air Leakage Control . . . . . . 14.7

Masonry Construction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.15

Housewrap. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.17

Window Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.19

Wall-to-Roof Flashing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.21

Interior Air Sealing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.23

Exterior Air Sealing with Insulating Sheathing Panels . . . . . . . . . . . . . . . . . . 14.27

Plumbing Air Sealing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.29

Electrical Air Sealing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.31

Installing Fiberglass Batt Insulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.33

Installing Windows in Walls with External Rigid Foam Insulation. . . . . . 14.35

Duct Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.39

Air Handler and Duct Sealing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.43

Ductless Heat Pumps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.45

Ice Dam Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.47

Case Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CS.1

Devoted Builders, Pasco, WA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

East Liberty Development, Inc./S&A Homes, Pittsburgh, PA . . . . . . . . . . . . . . . . 1

Nelson Construction, Farmington, CT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Rural Development, Inc., Turners Falls, MA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Shaw Construction, Aspen, CO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Appendices

I. Homebuyer’s Checklist. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A1.1

II. DOE Building Energy Code Resource Center Code Notes . . . . . . . . . . . . . A2.1

III. Energy & Housing Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A3.1

IV. Acronyms and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A4.1

vii Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011

BUILDING AMERICA BEST PRACTICES SERIES
“Teaming with Building America is 

a great marketing tool because we 

can honestly say we are building 

houses better.”

Chris Nelson, President of Nelson Construction, Farmington, Connecticut

Constructing energy-efficient, durable, and comfortable homes 

makes economic sense—for the builder, the consumer, the real estate 

professional, and the environment. In a time of significant challenges 

for the real estate community, Building America builders have 

made an important discovery—their homes are selling while their 

competitors’ homes are not. They are making some other exciting 

discoveries as well. They are having fewer callbacks and complaints. 

Instead, buyers are calling to thank them for lower utility bills. 

Builders of all sizes are discovering the benefits of teaming with 

Building America. In fact, nine of the nation’s ten largest builders in 

2009 were Building America partners. 

Learn what hundreds of builders across the country have already 

discovered—it isn’t difficult to build energy-efficient homes that 

are more healthy, durable, and comfortable to live in, while cutting 

energy bills nearly in half. Building America will help show you how. 

This guide can help you apply Building America research to your 

own projects to achieve energy savings of 40% over the Building 

America benchmark (a home built to the 1993 Model Energy Code). 

Using these whole-house building principles, your homes will meet 

and exceed the new 2009 International Energy Conservation Code 

(2009 IECC) and the 2009 International Residential Code (2009 

IRC). Whether you’re a multi-state builder with managers, sales 

staff, designers, site superintendents, and installers on your staff, 

Chapter 1.

Welcome

Chapter 1. Welcome 

Argument for Energy-Efficient Construction

Chapter 2. The Business Case 

Chapter 3. Business Management Tools 

Chapter 4. Selling Performance 

Cold Climate Building Science Basics

Chapter 5. The Cold Climate 

Chapter 6. Building Science 

Design Recommendations

Chapter 7. Building Envelope 

Chapter 8. Sub-Assemblies 

Chapter 9. Mechanical/Plumbing/ Electrical 

Chapter 13. Checklist 

Installation Guidance 

Chapter 10. Health and Safety

Chapter 11. Inspecting and Commissioning

Chapter 12. Construction Site Contracts, 

Scheduling, and Training

Chapter 14. Field Guides for Installers

Case Studies: 

• Devoted Builders, Pasco, WA

•	 East Liberty Development, Inc./

S&A Homes, Pittsburgh, PA

• Nelson Construction, Farmington, CT

• Rural Development, Inc., Turners Falls, MA

• Shaw Construction, Aspen, CO

Appendices:

I. Homebuyer’s Checklist

II. DOE Code Notes

III. Glossary

IV. Acronyms

1.1

CHAPTER 1. WELCOME

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 1.1
The 2009 IECC and 2009 IRC mandate a 

significant increase in energy efficiency 

in new home construction. Changes in 

these codes represent an approximate 

15% improvement in energy efficiency 

over the 2006 IECC. This guide will help 

builders meet and exceed these new 

requirements. The 2009 IECC and 2009 

IRC requirements are noted in green 

throughout this guide.

Building America welcomes 

reader feedback on all volumes 

of the Best Practices Series.

Please submit your comments via 

e-mail to: George James 

(George.James@ee.doe.gov). 

(top) Nelson Construction worked with DOE’s 

Building Science Consortium to achieve HERS 

scores in the low 50s on houses such as the 

one above in Farmington, Connecticut.

(bottom) East Liberty Development, Inc., 

and S&A Homes teamed with DOE’s IBACOS 

research team to build six highly efficient 

homes in inner-city Pittsburgh as part of a 

neighborhood revitalization.

or a small builder wearing many of these hats yourself, this guide 

can help you understand and apply the latest building science to 

differentiate yourself in a struggling new-construction market and 

to meet the new tougher energy codes.

Break open this guide and you’ll find the following:

Chapters 2 through 4 provide the data to make the case to upper 

management, yourself, and your shareholders for the value of energyefficient construction, including research on consumer preferences, 

competitive advantage, and incentives. Here you’ll also find business 

management tools, sales training tips, and marketing strategies. 

Chapters 5 and 6 explain the whole-house approach to building 

science and special considerations for building in the cold and very 

cold climate. 

Chapters 7 through 9 provide construction recommendations to 

architects and engineers based on Building America research, 

with guidance on best practices for meeting and exceeding code 

in regard to moisture management, insulation, and air sealing of 

home foundations, walls, and roofs. Guidance is also provided on 

windows, heating, air conditioning, ventilation, plumbing, and 

electrical systems. Occupant safety and health related to equipment 

installation issues are discussed in Chapter 10. Chapter 11 provides 

guidance on inspecting and commissioning. Chapter 12 covers 

construction contracts, scheduling, and training. Chapter 13 

provides a useful checklist of all of these recommendations. 

Chapter 14 provides handy two-page how-to field guides on 

specific energy-efficiency measures for installers.

Throughout the ensuing chapters, real-life examples are highlighted 

from exceptional builders in the cold and very cold climates. Case 

studies at the back of the report tell how five builders achieved 

significant energy savings using Building America practices. 

Finally, appendices provide a homebuyers’ checklist, a DOE–

sponsored resource for meeting codes, a glossary, and acronym list.

For More Information

You can learn more about Building America and download additional 

copies of this document, other best practices, case studies, and research 

reports at www.buildingamerica.gov.

CHAPTER 1 / BUILDING AMERICA BEST PRACTICES SERIES

1.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
The number one reason identified by builders for building energyefficient homes is to differentiate themselves from their competition 

(NAHBRC 2007). Builders who use Building America principles are 

among the most successful in the United States today.

Builders and Building America

Building America has worked with production builders since 1995 

to improve the energy efficiency, durability, comfort, environmental 

performance, and quality of new homes. Building America and 

its partners have conducted building science field research with 

builders throughout the country to test techniques, materials, and 

processes in real-world situations. As of August 2010, the program 

has contributed directly to the energy-efficient construction of more 

than 42,200 homes, and builders and vendors that have worked with 

Building America have influenced over a million new homes. 

Nine of the nation’s ten largest builders are Building America 

partners. Twenty-three of Building America’s 350+ builder partners 

made Builder Magazine’s Builder 100 list of the top 100 builders of 

2009 (based on home sale closings). While new home starts in 2009 

dropped to their lowest on record since 1959, twelve of Building 

America’s partners moved up in the Builder 100 rankings. 

Qualifying for programs such as DOE’s Builders Challenge and 

ENERGY STAR provides an easy way to show consumers that 

your company’s homes are a cut above the competition.

Chapter 2.

The Business Case 

for Building HighPerformance Homes

“Working with Building America 

helped us understand there is 

serious return on investment when 

you put these energy-efficiency 

features into your house.” 

Todd Winnor, project manager, 

S&A Homes, Pittsburgh

CHAPTER TOPICS

2.1 Builders and Building America

2.2 The Business Case for 

Energy Efficiency

R

Learn more about Building America at 

www.buildingamerica.gov.

2.1

CHAPTER 2. THE BUSINESS CASE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 2.1
Builders Challenge

The Builders Challenge label prominently features the EnergySmart Home Scale 

(or E-Scale), which shows a Home Energy Rating System (HERS) score. A house 

built to the 2006 IECC would score 100; a home that uses no more energy than it 

can produce with onsite generation such as solar panels would have a HERS score 

of 0. Builders Challenge homes must score 70 or lower.

The Business Case for Energy Efficiency

The world of new home construction is not the same place it was five 

years ago. The pace of new construction is still down in most markets. 

The good news is the public’s awareness of energy efficiency is up and in 

most markets around the country builders who emphasize energy-efficient 

construction have found that they are outselling their competition. 

The business case for high-performance, energy-efficient 

construction is straightforward and is based on the following points:

1. Consumers prefer energy-efficient homes.

2. Builders can use energy efficiency and other high-performance 

features to gain competitive advantage. Consumer preference and 

competitive advantage lead to more and faster sales.

3. Building America homes can meet energy-efficiency goals at no 

net increased costs to homeowners when added costs are balanced 

with utility savings.

4. New state and federal building codes are now a driving force in 

energy-efficient construction.

S

H O M

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Meets The Builders Challenge

Recognizing the best energy performance, quality, comfort, health and safety in the market.

Conditioned floor area (sq. ft.):

SM

Estimated annual energy usage:

www.buildingamerica.gov/challenge

55

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Electric (kWh) 10101

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Rating conducted January 28th, 2009

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Annual Energy Savings:

$1496

Building America builders ranked highest 

in overall customer satisfaction in 11 of 17 

new home markets and were among the 

top three in all 17 markets surveyed by J.D. 

Power in 2010. Building America builders 

Shea Homes and Standard Pacific Homes 

each took highest ranks in three markets 

and KB Homes took highest rank in two 

markets. Building America builders also 

ranked in the top three in all 17 markets in 

J.D. Power’s new-home quality study. Other 

Building America partners that placed 

highly include Centex, David Weekley 

Homes, Del Webb, DR Horton (shown 

here), John Wieland, K. Hovnanian, Lennar, 

Pardee Homes, Pulte, Ryan, and Ryland 

(J.D. Power press release 9/15/2010).

“In this hypercompetitive market, 

green features have become a 

crucial selling point, since newhomebuyers are seeking to save 

on energy costs, as well as to 

increase the value of their home.” 

Dale Haines, senior director of the real 

estate and construction industries 

practice at J.D. Power and Associates 

(J.D. Power press release 9/15/2010).

CHAPTER 2 / BUILDING AMERICA BEST PRACTICES SERIES

2.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Consumer Preferences

McGraw Hill Construction (2009) reports that “green building has 

grown in spite of the market downturn. Green seems to be one area of 

construction insulated from the downturn, and we expect green building 

will continue to grow over the next five years, despite negative 

market conditions, to be a $96–$140 billion market.” Most of the 

features listed by McGraw Hill in defining a green building involved 

energy efficiency. The report notes that green construction can help 

differentiate builders and stabilize their business in a struggling 

market. McGraw Hill also found word-of-mouth referrals are 

the most likely way that consumers learn about green home builders 

(McGraw Hill Construction 2009).

Surveys show that consumers want energy efficiency and they are 

willing to pay for it:

•	 87% of homebuyers said a greener, more energy-efficient home 

is a priority in a Better Homes and Gardens Magazine survey 

(Patterson 2010).

•	 94% of builders report that their buyers want more energy-efficient 

new homes; 55% said buyers specifically want ENERGY STAR®

homes (NAHB 2009). 

•	 Most builders (69%) indicated that some of their buyers are willing 

to pay extra for green amenities; 9% indicated that most were. 25% 

of builders said buyers want homes with more recycled materials 

and less material use overall (NAHB 2009). 

•	 91% of homebuyers preferred an energy-efficient home with lower 

utility bills to a cheaper home (sales price 2% to 3% lower) without 

the energy-efficient features (Rice 2009). 

•	 Homebuyers are willing to pay on average $6,000 more for their 

new home to save $1,000 annually on energy costs (Rice 2009).

•	 86% of Americans would choose one home over another based on 

its energy efficiency. Yet 78% of the homeowners polled said no one 

talked to them about energy efficiency during the buying process 

(National Builder News, April 9, 2007).

•	 Energy improvements topped the list of how homeowners would 

spend an extra $5,000 on their new homes (NAHBRC 2009).

•	 90% of new homebuyers are willing to spend more for energy 

efficiency—up to $17,000 more (McGraw Hill 2007).

•	 84% listed energy efficiency as the most important factor in 

their appliance purchases (Maynard 2009).

Building America Partners on 

Builder Magazine Top 100 List 2009 

Ranking Building America Partner

1 D.R. Horton

2 Pulte

3 Lennar

5 KB Home

6 Centex

7 K. Hovnanian

8 Habitat for Humanity Int’l

9 The Ryland Group

10 Beazer Homes USA

11 Meritage Homes Corp

12 Standard Pacific Corp

13 Taylor Morrison Homes 

17 David Weekley Homes

18 Weyerhaeuser Real Estate Co

20 Shea Homes

29 William Lyon Homes

32 WCI Communities

44 Mattamy U.S. Group 

63 John Wieland Homes 

and Neighborhoods

64 ICI Homes

67 Heartland Homes

71 Castle & Cooke

90 Ideal Homes

Nine of the nation’s ten largest builders are 

Building America partners. Twenty-three of 

Building America’s 350+ builder partners 

made Builder Magazine’s Builder 100 list 

of the top 100 builders of 2009 (based on 

home sale closings) in a very difficult year 

for U.S. home builders. 

“The downturn of the housing 

market—along with intensified 

competition for a very limited pool 

of homebuyers—has reinforced the 

importance of customer focus for 

new-home builders. Many builders 

that were unable to maintain this 

focus consistently have had to exit 

the marketplace.” 

Dale Haines, senior director of the real 

estate and construction industries practice 

at J.D. Power and Associates. “

(J.D. Power press release 9/15/2010) 

2.3

CHAPTER 2. THE BUSINESS CASE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 2.3
Nelson Construction of Farmington, 

Connecticut, teamed with Building America 

research partner Building Science Corporation 

to cut energy use by 50% compared to the 

Building America benchmark.

Competitive Advantage

Competitive advantage is critical, especially in a down market when 

buyers are few and their choices abound for new and existing homes. 

In 2009, Nelson Construction experienced a high volume of sales 

at its Hamilton Way development in Farmington, Connecticut, in a 

market that had almost completely stopped. Nelson built 10 Builders 

Challenge homes and all sold within 2 months of completion.

“My utility bills went through the roof in 2009. Anyone who was 

looking to buy was definitely considering what kind of performance 

their house was going to get,” said Peter Baker, a senior associate 

with Building Science Corporation who helped Nelson achieve 

energy savings of 50% over the Building America benchmark.

Building America analysis predicted annual utility savings of $2,429 

to $3,070 on the 2,960- to 3,540-square foot homes, compared to 

the Building America benchmark, based on local utility rates of 

$0.16/kWh or $1.60/therm.

“‘Building Better’ is now the tag line for Nelson Construction. It 

has become part of our company identity that we build energyefficient, healthy, sustainable homes,” said Chris Nelson, president 

of Nelson Construction.

Nelson adds: “Now we have a marketing advantage. We are looked 

at as one of the experts in the industry related to energy efficiency. 

From the developer’s side, it helps us get approvals, which is really a 

big deal and nothing we were thinking about when we decided to do 

this. Towns want to work with builders who are doing things better.”

Cost-Neutral Energy Savings

Building America case studies prove that energy-efficient 

construction does not have to cost more for homebuyers. Tradeoffs 

in building material choices, streamlining of processes, and tax 

incentives and rebates can minimize cost increases for builders.

Building America builders have experienced upfront cost savings in 

numerous ways that balance out against the increased costs of some 

energy-efficiency measures. For example, they have used advanced 

framing techniques, which cut down on lumber costs; designed 

on a 2-foot grid to reduce materials cost and waste; downsized 

HVAC equipment through better insulation and air sealing of the 

building envelope and right sizing of equipment; and substituted 

How homeowners would 

spend an extra $5,000 

on their new homes 

(Figure source: NAHBRC) 

 26% would pay for energy improvements

 22% for new countertops 

 23% for other

 17% for upgraded flooring

 6% for upgraded appliances

 5% for upgraded bathroom features

 1% for new siding

“The longer they [builders] wait 

to build energy-efficient houses, 

the further behind they are going 

to be. It’s definitely what buyers 

are looking for. It is better to be 

proactive than reactive.” 

Rich Coyle, vice president for building 

science at DR Horton’s Sacramento division

CHAPTER 2 / BUILDING AMERICA BEST PRACTICES SERIES

2.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
“We sold all of our homes in 

less than two months. The people 

who were buying our homes 

wanted to buy something that 

was built better.” 

Chris Nelson, president of Nelson 

Construction, Farmington, Connecticut, 

who teamed with Building America on 

10 homes that sold at $649,000 and up 

in a dead market.

rigid foam for structural panel sheathing for better performance at 

neutral cost. They’ve cut labor costs by spray foaming rather than 

individually caulking rim joists, by shortening and simplifying duct 

runs, and by moving ducts out of awkward crawlspaces and attics 

into conditioned space. Builders have reduced construction time and 

money by prefabricating duct components on the ground and by 

factory-building frame wall components or using structural insulated 

panels (SIPs). They’ve streamlined processes, realized savings from 

vendors, reduced or eliminated callbacks, and cut back on costly 

schedule overruns through good upfront planning with integrated 

management techniques, ongoing training of subcontractors, and 

interim and final inspections and commissioning.

Case Studies Prove Homebuyers Profit

In 2007 through 2010, Building America researchers worked with 

five builders in the cold climate to build more than 161 homes that 

met or exceeded 40% energy savings. In each of those projects, 

homeowners’ utility bill savings yielded a net profit each year, after 

subtracting increased mortgage costs. Researchers from Building 

Science Corporation modeled one house plan from each builder using 

EnergyGauge and BEopt software. Table 2.1 shows the energy cost 

savings calculated for each builder’s home, the incremental increase 

in the annual mortgage to cover the costs of the energy-efficiency 

features versus the cost of a mortgage for a typical house, and the net 

annual cash flow to the homebuyer. In every case the homebuyer came 

out ahead, with net gains ranging from $277 to $1,392 per year. These 

examples show how homebuyers can realize a positive return from 

energy-efficiency improvements no matter how the stocks and bonds 

markets are doing.

Table 2.2 details costs associated with one builder’s choices in 

energy-efficient features. The builder, Rural Develoment, Inc., spent 

$11,800 more per unit to add energy-efficiency measures they had not 

incorporated into previous projects, including a solar water heater, 

triple-pane windows, and double-stud walls. Some changes may 

actually cut costs; in this case switching from an oil boiler to a highefficiency gas space heater saved the builder $5,000 per unit. When 

these costs are added to the sale price of the home (at a 10% markup) 

and incorporated into a 30-year mortgage at 7% interest, it adds 

$1,050 per year to the homeowner’s mortgage but calculated utility 

savings are $2,192 annually per home, so the homeowner actually nets 

a profit of $1,142 per year.

Energy-Saving Features Are “In” 

Energy-saving features are “in” according to 

builders polled by the National Association 

of Home Builders at the 2010 NAHB 

International Builders’ Show in Las Vegas, 

in January 2010. When builders were given 

a list of 40 features and asked which ones 

they were likely to include in new homes, 

five of their top ten choices were energyrelated. “Builders will focus heavily on 

energy-saving features. Things we thought 

were consumer necessities—such as granite 

countertops in the kitchen or home offices—

are not on the list,” Rose Quint, assistant 

vice president for NAHB’s Survey Research 

Economics and Housing Policy Group, told 

media at the 2010 NAHB International 

Builders Show (RREA 2010).

Items most likely to be found 

in new homes for 2010 (NAHB):

1. Walk-in closet in master bedroom 

2. Separate laundry room 

3. Insulated front door 

4. Great room 

5. Low-E windows 

6. Linen closet 

7. Programmable thermostat 

8. Energy-efficient appliances 

and lighting 

9. Separate shower and tub 

in master bedroom 

10. Nine-foot ceilings on first floor 

(instead of 2-story foyer)

2.5

CHAPTER 2. THE BUSINESS CASE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 2.5
Table 2.1. Cold Climate Case Study Costs and Savings

Every Building America project yielded net annual gains for homeowners, after deducting increased mortgage costs from annual 

utility bill savings.

Builder

Cost Increase 

for Energy 

Improvements

Added Annual 

Mortgage Cost for 

Energy Efficiency

Annual Utility 

Bill Savings vs. 

Benchmark

Net Annual 

Cash Flow

Devoted Builders $10,000 $809 $1,333 $524

East Liberty Development, Inc./S&A Homes $9,900 $792 $1,699 $907

Nelson Construction $25,740 $2,055 $3,447 $1,392

Rural Development, Inc. $11,850 $1,050 $2,192 $1,142

Shaw Construction $6,200 $498 $775 $277

In every case study, the energy-efficiency improvements are actually money makers for the homeowners.

Utility bill savings relative to the Building America benchmark were calculated by Building Science Corporation using EnergyGauge 

and BEopt 0.8.6 software. Cost increases are based on builder estimates and additional data sources such as RS Means, DEER, 

supplier cost bids, etc. A 10% markup is assumed and the cost is converted into an annuity assuming a 7% loan over 30 years. Inflation, 

incentives, and rebates are not considered. For multi-family buildings, costs are estimated per-unit costs. The Building America 

benchmark is a home built to the 1993 Model Energy Code.

Table 2.2. How Much Does it Cost to Reach 40% Energy Savings? 

One Example in the Cold Climate

The example shown here is for a typical 1,390-ft2, 2-story, 3-bedroom, 2-bath, home built by Rural Development, Inc. (RDI), in 

Greenfield, Massachusetts. Estimated costs for energy-efficiency measures are listed in the table below. As shown, when increased 

mortgage costs are balanced against utility savings, the homeowner comes out ahead $1,142 each year.

Energy-Efficiency Feature Added Cost, per Home, Over 

Builder’s Conventional Practice

Double-wall construction $2,500

R-50 attic insulation $300

R-40 floor insulation $540

Triple-pane windows $3,000

Solar water heating system $9,750

Heating system ($5,000)

Ventilation system $450

100% CFL lighting $114

ENERGY STAR appliances $190

Total $11,844

Annual cost (when incorporated into a 30-year loan at 7% interest) $1,050

Annual utility bill savings $2,192

Net Annual Cash Flow to Homeowner $1,142

Conclusion: These energy-efficiency improvements are actually money makers for the owner of this home.

Cost estimates were provided by the builder. A 10% markup is assumed; incentives and rebates are not considered.

CHAPTER 2 / BUILDING AMERICA BEST PRACTICES SERIES

2.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Federal, State, and Local Incentives and Tax Credits

Incentives can help offset costs as builders transition to more energyefficient construction materials. A wide range of incentives and tax 

credit opportunities are available at the federal, state, and local level. 

In addition to financial incentives for energy-efficient homes, some 

local governments offer streamlined permitting processes for green 

and energy-efficient projects. 

For information on what is available to you, visit the Database 

of State Incentives for Renewables and Efficiency (DSIRE), at 

www.dsireusa.org. DSIRE is a comprehensive source of information 

on state, local, utility, and federal incentives, tax credits, and policies 

that promote renewable energy and energy efficiency. Established 

in 1995 and funded by the U.S. Department of Energy, DSIRE is 

an ongoing project of the North Carolina Solar Center and the 

Interstate Renewable Energy Council.

Although the $2,000 Federal tax credit for building a new energy-efficient 

home expired on December 1, 2009, other tax credits for specific measures 

still exist; see www.energystar.gov/index.cfm?c=tax_credits.tx_index.

For new home construction, until December 31, 2016, a tax credit 

covering 30% of the cost (with no upper limit) is available for 

geothermal heat pumps, small residential wind turbines, and solar 

energy systems. Also available until December 31, 2016, is a 30% tax 

credit with up to $500 per 0.5 kW of power capacity for residential 

fuel cells and micro-turbine systems. This site provides easy-to-follow 

information about eligibility and applying for these tax credits.

The ENERGY STAR “Special Offer/Rebate Finder” website below 

enables a user to enter a zip code to receive accurate information 

about rebates and sales tax exemptions or credits for qualified 

products. These include most major appliances, residential ventilation 

fans, heating and cooling equipment, insulation, roof products, 

windows, doors, lighting, water heaters, and office equipment. See 

www.energystar.gov/index.cfm?fuseaction=rebate.rebate_locator.

ENERGY STAR has more information for builders interested 

in qualifying homes through ENERGY STAR’s new home 

program at www.energystar.gov/index.cfm?c=bldrs_lenders_raters.

nh_benefits_builders.

Builders can check ENERGY STAR’s New Homes Partner Locator 

page for state contacts for locally administered builder incentives 

for new ENERGY STAR homes at www.energystar.gov/index.

cfm?fuseaction=new_homes_partners.locator.

“The market is tough and these are 

spec homes. People who bought 

were buying for energy efficiency, 

because of the location, and 

because of the quality.”

Eric Jester, project manager of East Liberty 

Development, Inc. who worked with the 

Building America team IBACOS and builder 

S&A Homes on an urban in-fill project, 

which sparked a turnaround in a struggling 

Pittsburgh neighborhood with increased 

housing values, decreased vacancy rates, 

and a 60% drop in crime rates.

S&A Home’s highly efficient Building 

America homes in Pittsburgh sold for 

$216,000 to $305,000 in a challenged 

neighborhood, where median prices had 

been well under $100,000.

2.7

CHAPTER 2. THE BUSINESS CASE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 2.7
For More Information on the Business Side of Building 

2009 IECC. 2009. International Energy Conservation Code, International Code Council (ICC), 

Washington, D.C. www.iccsafe.org/Store/Pages

2009 IRC. 2009. International Residential Code - One and Two-Family Dwellings, 

International Code Council (ICC), Washington, D.C. www.iccsafe.org/Store/Pages

Builders Magazine. 2009. “Builder 100.” www.builderonline.com

Caufield, John. 2010. “Hard Landing, The housing market may have finally hit bottom in 

2009,” Builder Online, posted May 4, 2010, www.builderonline.com/sales/hard-landing.aspx

Dakin, Willard, David Springer, and Bill Kelly. 2008. “Case Study: The Effectiveness of Zero 

Energy Home Strategies in the Marketplace.” In Proceedings of the 2008 ACEEE Summer 

Study on Energy Efficiency in Buildings, American Council for an Energy-Efficient Economy, 

Washington D.C.

J.D. Power and Associates. 2010. “Satisfaction with New-Home Builders and New-Home 

Quality Reach Historic Highs, as Home Builders Respond to Tough Market Conditions by 

Improving Products and Service,” press release 09/15/2010, http://businesscenter.jdpower.

com/news/pressrelease.aspx?ID=2010177

Maynard, Nigel F. 2009. “New Survey Finds Energy, not Water, Drives Appliance Purchases.” 

Builder Magazine, March 27, 2009. www.builderonline.com/appliances/survey-finds-energydrives-appliance-purchases.aspx

McGraw Hill Construction. 2009. 2009 Green Outlook: Trends Driving Change. 

http://construction.com/market_research/reports/GreenOutlook.asp.

Nation’s Building News. 4/9/07. “Builders Need to Make Energy Efficiency a Selling Point.” 

Energy Pulse Survey by Shelton Group, reported in Nation’s Building News Online. 

National Association of Home Builders. www.nbnnews.com/NBN/issues/2007-04-09/

Front+Page/index.html

Nation’s Building News. 4/16/07. “In a Down Housing Market, Green Demand Exceeds 

Supply.” Nation’s Building News Online. National Association of Home Builders. 

www.nbnnews.com/NBN/issues/2007-04-16/Front+Page/index.html

National Association of Home Builders (NAHB). 2009. “Baby Boomers Want Convenience 

and Energy Efficiency in New Homes According to New Survey,” news release 9/15/2009 

www.nahb.org/news_details.aspx?sectionID=1196&newsID=9696/

NAHBRC. 2007. Building America Challenge Survey of Builders and Consumers. Proprietary 

survey commissioned by DOE and conducted by the NAHBRC as part of the Annual 

Consumer Practices Survey. National Association of Home Builders Research Center, 

Upper Marlboro, MD.

Patterson, Jean. 2010. “Buyers seek smarter and smaller homes, survey says,” The Seattle 

Times, Feb. 8, 2010, http://seattletimes.nwsource.com/html/homegarden/2011019068_

cozyhomes09.html

Register Real Estate Advisors. January 25, 2010. “What do homebuyers want in 2010?” 

http://rrea.com/news/what-do-homebuyers-want-in-2010-builders-hope-they-know/

Rice, Alison. 2009. “Consumers Rethink Home-Buying Priorities,” Builder 2009. 

January 22, 2009. www.builderonline.com/housing-trends/consumers-rethink-homebuying-priorities.aspx

In a 2010 study of 16,400 new 

homebuyers, market research 

organization J.D. Power found that newhome builders are increasingly using 

green and energy efficiency features 

as a selling point—65% of new home 

builders identified the green features 

of their homes to homebuyers in 2010, 

up from 48% in 2009, and 61% of new 

homebuyers perceived their new home 

as environmentally friendly, compared 

with only 31% in 2009. 

“We benefitted greatly from 

this project, not only from the 

exposure, but from learning what 

it takes to get to the 40% mark.” 

Todd Winnor, project manager 

S&A Homes, Pittsburgh

CHAPTER 2 / BUILDING AMERICA BEST PRACTICES SERIES

2.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Codes as Drivers

New building energy codes are now a driving force in energy-efficient 

construction. 

The International Energy Conservation Code

The 2009 International Energy Conservation Code (2009 IECC) 

was published in December 2008 and has gotten a boost in adoption 

from the American Recovery and Reinvestment Act (ARRA) 

of 2009. States seeking funding for building programs through 

the Act must show that they have adopted building energy codes 

for residential buildings that meet or exceed the 2009 IECC. The 

provisions of the 2012 IECC were finalized at the Final Action 

Hearings in November 2010. 

State Energy Codes

There are 34 states that are wholly or partially in the cold or very 

cold Building America climate zones (which correspond to IECC 

climate zones 5, 6, 7, and 8; see maps in Chapter 5.) The status of 

residential energy code adoption in each state (as of January 5, 

2011) is summarized in the map below. Several of these states have 

recently undertaken or are in the process of adopting building energy 

code revisions and many expect to adopt IECC 2009 by June 2013 

including the following: CT, FL, HI, MI, MN, NC, NE, NM, NV, 

OH, OR, SC, TX, UT, VA, VT, WI, and WV. Table 2.3 provides 

additional details on each state’s energy code adoption status and 

planned activities. (See www.energycodes.gov/states for up-to-date 

state information on energy code adoption). 

Status of Residential Energy Codes in Cold Climates

“Everyone needs to understand 

that the difference between the 

way we have been building in the 

past and the way we have to build 

now is night and day. Everyone 

complains about what a pain the 

change in codes is, but I think we 

have to start being smarter about 

how we build.”

Todd Winnor, project manager 

S&A Homes, Pittsburgh

For More Information on Codes

2009 IECC. 2009. International Energy 

Conservation Code, International Code 

Council (ICC), Washington, DC. 

www.iccsafe.org/Store/Pages

2009 IRC. 2009. International Residential Code - 

One and Two-Family Dwellings, International Code 

Council (ICC), Washington, DC. 

ww.iccsafe.org/Store/Pages

Building Energy Codes Program. U.S. Department 

of Energy Office of Energy Efficiency and 

Renewable Energy, 

www.energycodes.gov

“Working on this project with Building 

America made me realize this is the way of 

the future. There is no getting around this. 

For years, builders tried to save dollars here 

and there. Code changed big time in 2009 

and a lot of builders were not ready for it. 

Working with Building America has put 

us ahead of the curve,” said Todd Winnor, 

project manager, S&A Homes, Pittsburgh.

*Adoption by county/jurisdiction above state-mandated minimum

American Samoa

Guam

N. Mariana Islands

Puerto Rico

U.S. Virgin Islands

IL* IN

MI

OH

PA

NY

VTNH

ME*

MA

CT RI

NJ

DE

DC

MD

VA WV

KY

TN*

MS*

LA

AL*

SC

NC

FL

GA

IA

*MO

MT

WA

OR

NV

ID

UT

HI*

AK

CA CO*

WY*

SD*

ND*

NE

KS*

OK* AZ* NM AR

TX*

WI

MN

IECC 2009, 

equivalent or 

more stringent

IECC 2006, 

equivalent or 

more stringent

IECC 2003, 

equivalent or 

less stringent

No Statewide Code

(as of Jan. 5, 2011)

2.9

CHAPTER 2. THE BUSINESS CASE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 2.9
Table 2.3. Status of Energy Code Adoption in U.S. Cold Climate States (as of August 2010)

States Statewide 

Residential Code

Adoption by Local 

County/Jurisdiction Notes

Alaska State Specific Mandatory The Building Energy Efficiency Standard (BEES) uses the 

2006 International Energy Conservation Code, with AlaskaSpecific Amendments. The state code includes an optional 

performance-based compliance approach that is completely 

separate from the IECC. A home that receives an energy rating 

and achieves a level of four stars using the AKwarmTM method 

meets the state code. The Alaska Housing Finance Corporation 

reports that code compliance is “most often shown” by 

this method.

Arizona None Voluntary Many jurisdictions have adopted the IECC editions and some 

have adopted advanced energy codes. 

California State Specific Mandatory State-developed code, Part 6 of Title 24, which exceeds 2009 

IECC. (New 2008 Standard, became effective 

Jan. 1, 2010)

Colorado 2003 IECC Yes Mandatory in any area that does not adopt or enforce 

local codes. 

Connecticut 2006 IECC Mandatory 2006 IECC with amendments effective August 1, 2009. 

Iowa 2009 IECC Mandatory

Idaho 2009 IECC Mandatory 2009 IECC effective January 2011

Illinois 2009 IECC Mandatory

Indiana State Mandatory State code based on 92 MEC, currently updating to the 

2009 IECC 

Kansas None Yes Homebuilders or realtors must disclose information about the 

home energy performance parameters on the Kansas Energy 

Efficiency Disclosure Form

Massachusetts 2009 IECC Mandatory 2009 IECC with amendments

Michigan 2003 IRC Mandatory 2003 IRC with reference to 2004 IECC supplement, currently 

in the process of updating to 2009 IECC

Minnesota State Mandatory Based on 2006 IRC with amendments, very prescriptive

Missouri None Voluntary None statewide. State-owned single-family and multi-family 

residential buildings must comply with the latest edition of the 

MEC or ANSI/ASHRAE Standard 90.2-1993.

Montana 2009 IECC Mandatory

CHAPTER 2 / BUILDING AMERICA BEST PRACTICES SERIES

2.10 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
States Statewide 

Residential Code

Adoption by Local 

County/Jurisdiction Notes

Nebraska 2003 IECC Mandatory

New Hampshire 2009 IECC Mandatory

New Jersey 2009 IECC Mandatory 2009 IECC with amendments. 

New Mexico 2006 IECC Mandatory In the process of adopting a new residential code that 

is 20% more stringent than the 2006 IECC. Currently out 

for public review. 

Nevada 2006 IECC Mandatory

New York 2009 IECC Mandatory 2009 IECC with amendments, effective December 2010.

North Carolina 2006 IECC Mandatory 2006 IECC with amendments. No HVAC trade-offs are allowed 

and 0.40 SHGC or better required in all climate zones.

North Dakota None Voluntary 2006 IRC and IECC contingent upon local adoption 

effective August 1, 2009.

Ohio 2006 IECC Mandatory With alternative prescriptive path www.com.state.oh.us/dic/

Documents/bbst_PARTA-Residential.pdf

Oregon State Mandatory State-developed code based on the 2006 IRC.

Pennsylvania 2009 IECC Mandatory

Rhode Island 2009 IECC Mandatory 2009 IECC became effective July 1, 2010.

South Dakota None Voluntary 2006 IECC is voluntary.

Utah 2006 IECC Mandatory 2009 IECC for multi-family high-rise and low-rise buildings. 

2006 IECC for one- and two-family dwellings.

Vermont State Mandatory Based on the 2000 IECC with amendments. 

2009 IECC rulemaking due by January 1, 2011.

Washington State Mandatory State-developed code based on 2009 IECC, 

effective Jan. 1, 2011. 

Wisconsin State Mandatory State developed code meets/exceeds 2006 IECC.

West Virginia State Mandatory 2003 IECC with amendments. 2006 IECC is encouraged.

Wyoming None Voluntary Adoption by jurisdiction, City of Cheyenne adopted 

2006 IRC.

2.11

CHAPTER 2. THE BUSINESS CASE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 2.11
For builders who want to build high-performance homes and achieve 

a healthy bottom line, sound business systems are a critical part of 

the picture. 

This chapter introduces the following four practices to aid in 

construction planning and management: 

•	 quality management 

•	 integrated design 

•	 value engineering 

•	 prototype development. 

Each of these four practices has value on its own, but they work best 

when applied as part of an overall management system suited to an 

individual business.

Quality Management 

Three terms are often used when describing quality programs: 

quality management, quality assurance, and quality control. These 

terms are described below, based on the definitions provided by the 

American Society for Quality (www.asq.org).

•	 QUALITY MANAGEMENT: a process for achieving maximum 

customer satisfaction at the lowest overall cost to the organization 

while continuing to improve the building process. A quality 

management system documents the structure, responsibilities, 

and procedures required to achieve your company’s goals. A 

related term—total quality management—refers to all members 

of an organization participating in improving processes, products, 

services, and the culture in which they work.

Chapter 3.

Business 

Management Tools

Builders learn quality management 

concepts at a Building America workshop, 

conducted by Building America research 

team lead IBACOS.

“We have seen a direct impact 

on our quality through the 

Building America program. We 

are able to build a better product 

because of our consistent 

approach [in implementing 

Building America practices].” 

Josh Robinson, vice president of 

Operations for Pulte, North Inland 

Empire Division of California

CHAPTER TOPICS

3.1 Quality Management

3.4 Integrated Design

3.9 Value Engineering

3.10 Managing Innovation 

with Prototypes

3.1

CHAPTER 3. BUSINESS MANAGEMENT TOOLS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 3.1
•	 QUALITY ASSURANCE: the planned and systematic activities 

that provide confidence that a product fulfills requirements for 

quality. These activities may include tests, such as blower door 

tests, inspections, checklists, and systematic training. 

•	 QUALITY CONTROL: the operational activities used to fulfill 

requirements for quality. These activities include evaluations, such 

as statistical studies to evaluate product variation, expected failure 

rates, and corrective actions. 

Many companies formalize their quality management processes 

and practices. Other companies simply incorporate tools into their 

business practices that help to improve quality. Some companies 

choose to become certified under third-party quality assurance 

programs. The important point is to plan for quality.

Building America’s Integrated Building and Construction Solutions 

(IBACOS) research team has developed comprehensive quality 

management guidelines for builders. The recommendations 

encompass all facets of the builder’s organization including 

leadership, strategic planning, customer satisfaction, performance 

management, jobsite responsibilities, safety, workforce development, 

quality construction processes, and trade contractor and supplier 

partnerships. This operations evaluation is based on the National 

Association of Homebuilders Research Center’s National Housing 

Quality Program. The recommendations can be found in Appendix 

D of the report, Achieving 30% Whole-House Energy Savings Level 

in Marine Climates, prepared by Building America’s research teams 

(DOE 2006) and available at http://apps1.eere.energy.gov/ buildings/

publications/pdfs/ building_america/39743.pdf. 

In accordance with these guidelines, Building America recommends 

that a quality management approach include these four ingredients: 

•	 TRAINING AND EDUCATION – for builders, trades, and sales 

staff (including participating in certification programs); see 

Chapter 12 for more information on training

•	 OPERATIONAL EVALUATION – described above and in DOE 2006

•	 PERFORMANCE-BASED STANDARDS – described throughout 

this guide; examples include DOE’s Builders Challenge and EPA’s 

Thermal Bypass Checklist

•	 VERIFICATION/COMMISSIONING/FEEDBACK – testing and 

inspections; see Chapter 11 for more details.

New Tradition Homes in Washington 

State, incorporates these elements in 

its quality management program: an inhouse building science team, a corporate 

commitment to energy efficiency, ongoing 

training of staff, participation in federal 

and regional energy-efficiency programs, a 

dedicated air sealing contractor, third-party 

performance testing, in-house marketing 

research, and an ongoing, interactive 

relationship with their heating, ventilation, 

and air conditioning (HVAC) contractor. 

“While a quality home need not 

necessarily be a high-performance 

home, any high-performance 

home MUST be a quality home. 

The quality management 

approach is an essential element 

of the Building America approach 

to homebuilding because it is 

the main vehicle for moving from 

science to implementation.” 

Building Industry Research Alliance, 

a Building America research team lead

CHAPTER 3 / BUILDING AMERICA BEST PRACTICES SERIES

3.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
The final judge of quality is the consumer. If a builder consistently 

meets consumer expectations, the rewards are tremendous. 

Consumer research organization J.D. Power found that truly 

delighted homebuyers (those rating their builders a 10 on a 10-point 

scale) recommend their builder to nearly twice as many people as the 

average new homebuyer (J.D. Power 2008).

BUSINESS MANAGERS

Excavation

Concrete

Framing

Sheathing

Housewrap

HVAC

Plumbing

Cladding

Sheet Rock

Trim

Finish

Insulation

Air Sealing

Electrical

BUSINESS MANAGERS Share house 

designs with company divisions. Develop 

and support implementation of a quality 

management system.

CONSTRUCTION MANAGERS / 

MATERIALS PURCHASERS Interact directly 

with trade contractors to develop mutually 

agreeable scopes of work, checklists, and 

test and inspection protocols. Interact with 

customers to manage expectations and 

ensure satisfaction. 

TRADE CONTRACTORS Ensure that the

project is ready for your work to start. 

Perform work according to plans, 

specifications, manufacturer’s installation 

instructions, and local codes. Perform final 

inspection to ensure work is performed 

according to your own standards and those 

of the builder. Confirm that the project is 

ready for next trade to begin work.

TRADE HAND-OFFS 

where job-ready and job-complete checklists are done.

HOMEBUYER 

MARKET

DESIGNERS Ensure construction 

documents include clear diagrams of 

critical details and specifications for 

required materials and equipment.

FIELD SUPERVISORS Work with trade 

contractors to ensure coordination, installation 

according to the plans and specifications, 

compliance with local code, and completion 

of company quality assurance processes.

➊

➋

➌

➍

➎

FIELD SUPERVISORS

CONSTRUCTION MANAGERS / MATERIALS

PURC

H

A

SER

S

TRADE CONTRACTORS

DESIGNERS

Close Out Testing

Quality Management Process Wheel

Information flows both to and from each part of the company including subcontractors.

3.3

CHAPTER 3. BUSINESS MANAGEMENT TOOLS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 3.3
For More Information on Quality Management

ASQ. 2008. ISO 9001:2000 Interpretive Guide for the Design and Construction Project Team. 

American Society for Quality Press, Milwaukee, WI. www.asq.org/quality-press.

2009 International Energy Conservation Code. Section 103.2, “Information on Construction 

Documents.” International Code Council (ICC), Washington, D.C. www.iccsafe.org/Store/Pages.

Building Science Corp. 2008. Quality Assurance Roadmap for High Performance Residential 

Buildings. Building Science Corporation. www.buildingscience.com/documents/guides-andmanuals/gm-building-america-quality-assurance-roadmap/view?searchterm=quality.

DOE. 2006. Building America Residential System Research Results: Achieving 30% 

Whole-House Energy Savings Level in Marine Climates, January 2006 – December 2006, NREL/

SR-550-39743, prepared by the Building America research teams BIRA, BSC, CARB, Davis 

Energy Group, FSEC, IBACOS, NAHBRC and NREL for the U.S. Department of Energy, 

http://apps1.eere.energy.gov/buildings/publications/pdfs/building_america/39743.pdf.

Haas Davenport, Linda. 2000. The Scopes of Work Program: Procedures and Standard to 

Increase Quality. NAHB BuilderBooks, Washington, D.C., http://store.builderbooks.com/cgibin/builderbooks.

ISO 9000. Quality Management Systems. International Organization for Standardization, 

www.iso.org.

NAHBRC. 2000. Quality Assurance System for Wood Framing Contractors: National Quality 

Housing. National Association of Home Builders Research Center. www.pathnet.org/

si.asp?id=478.

NAHBRC. 2008. Scopes of Work for High-Performance Homes. Prepared for the National 

Renewable Energy Laboratory by the National Association of Home Builders Research 

Center, Upper Marlboro, MD.

Integrated Design

The integrated design process, including energy-efficiency modeling 

and appropriate HVAC system sizing, is at the heart of Building 

America recommendations. Integrated design is a process by which 

all the various building subsystems are evaluated for the local 

climate and their interrelationships are analyzed, planned, and 

optimized. The goal is to gain value at every step of the design 

process (value engineering) rather than relying solely on negotiation 

and procurement to manage costs. 

Before World War II, a house was often designed and built under 

the watchful eye of a single person. As construction projects have 

become more complex and expertise has become more specialized, 

the decision-making, design, and construction processes have been 

divided among managers, designers, site superintendents, vendors, 

subcontractors, and the trades. Along with increasingly diverse 

teams, building materials and construction techniques have also 

multiplied and become more technical. 

The integrated design process invites today’s larger design and 

construction teams to share information and insights to achieve the 

kind of whole-house perspective and understanding that previously 

came with a single master builder.

“We have enjoyed our new Marsala 

townhome for about seven 

months. The integral concrete and 

insulation construction has made 

ours an extremely quiet, energyefficient and comfortable home.... 

Devoted Builders has certainly 

lived up to their name by their 

devotion and committment to the 

total quality of the Mediterranean 

Villas townhome community. We 

are glad to be here.” 

Mr. and Mrs. Stewart, homeowners 

at Devoted Builders’ Mediterranean 

Villas, Pasco, Washington, a Building 

America partner

CHAPTER 3 / BUILDING AMERICA BEST PRACTICES SERIES

3.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Builders who use the integrated design approach focus on wholehouse performance. They start by looking at how all the systems in 

the house (HVAC, insulation, walls, ceilings, and windows) work 

together to achieve a house that performs well in terms of energy 

efficiency, air quality, and moisture management. This investment 

in up-front planning is especially worthwhile for production builders 

because they reap the benefits with multiple applications of a 

house design.

In contrast, builders using typical design practices often start by 

emphasizing cost and size. With these external factors decided, they 

move through a linear process ending with house construction; 

building performance is considered as an afterthought or not at all.

Traditional Design Processes

Typically a design process includes the following steps.

1. PROGRAMMING: 

In this conceptual development and planning stage, the price range, 

square footage, number of stories, lot sizes, general features, and 

styles are determined.

2. SCHEMATIC DESIGN: 

Preliminary designs are developed including floor plan sketches, 

number of bedrooms, major options, basic circulation and function 

locations, as well as some elevation concepts.

3. DESIGN DEVELOPMENT: 

Preliminary structural, mechanical, electrical, and plumbing plans 

are drawn.

4. CONSTRUCTION DOCUMENTS: 

Final working drawings and specifications are ready for bidding 

and code approval.

The traditional design process tends to be linear, with input coming 

sequentially. Sometimes design decisions are made before the 

input is available. Sometimes the input is not part of the formal 

design process, but comes in the field where access to information 

is limited and decisions must be based on the materials, expertise, 

and conditions at hand. For example, HVAC equipment may not be 

sized until the installer shows up on the project site, and important 

decisions such as routes and sizes for ducts may not occur until 

installation work begins in the field.

When RDI designed its Solar Village 

in western Massachusetts, it used an 

expanded integrated design process and 

included architects, engineers, Building 

America staff, and trades (carpenters, 

plumbers, electricians, solar installers, etc.) 

in the initial planning meetings.

Related Standards & Procedures

•	 ISO 9000, Quality Management Systems 

www.iso.org

•	 2009 International Energy Conservation 

Code, Section 103.2 “Information on 

construction documents,” International 

Code Council (ICC), Washington, DC. 

Available for purchase at 

www.iccsafe.org/Store/Pages 

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Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 3.5
Integrated Design Process

A key idea behind integrated planning is that decisions about 

all building systems, including equipment selection, sizing, and 

placements, are made within the design process, not as afterthoughts 

in the field. The decisions are made with the help of analytical 

tools and the input of all relevant disciplines. Rather than a linear 

traditional process, the integrated process involves looping in 

ongoing input from relevant sources.

The following are steps within the integrated design process.

PRE-DESIGN – Bring together a diverse and knowledgeable team. 

The makeup of the team and members’ roles will vary depending 

on the project or objective under consideration. Community 

design may benefit from ecologists, landscape architects, or solar 

planners. House designs may need input from architects or designers, 

structural engineers, framers, and HVAC contractors. Solving a 

particular installation challenge could involve the site supervisor 

and the relevant trades. For larger-scale efforts, select a facilitator to 

carry the process forward and set up a schedule of needed meetings.

SET PERFORMANCE STANDARDS – Early in the design process, 

establish standards that the house model will be expected to achieve. 

Measure progress against these standards at each step. Use market 

data to determine the level of quality, performance, size, and cost 

the houses will achieve. Performance areas may include moisture 

management, indoor air quality, energy efficiency, HVAC comfort, 

and any certification requirements (for example, achieving a Home 

Energy Rating Scale (HERS) index score to qualify for a tax credit).

CONCEPTUAL AND PRELIMINARY DESIGNS – Gain team 

feedback during all phases of design and construction. Use 

an energy specialist to test design assumptions and simulate 

possible solutions. It is important to work with framing and other 

contractors, especially HVAC contractors, to identify conflicts and 

develop solutions before houses go into production. You may want 

to consult with code officials for any nonstandard techniques or 

materials. By integrating design decision-making, all parties benefit. 

For example, the mechanical contractor can aggressively size 

the HVAC equipment knowing that the thermal envelope is 

well insulated, properly air sealed, and third-party inspected.

Building America team IBACOS encouraged 

S&A Homes to use an integrated design 

approach and to design the home around 

the HVAC system when it built its urban 

in-fill homes on narrow city lots. 

“The idea is a whole-house 

system integration approach. We 

wanted to make sure the HVAC 

system and mechanicals were 

not an after-thought. A lot of 

builders put up the frame and 

don’t really consider where duct 

lines and supply risers need to go 

or how the plumbing lines and 

drain lines may be routed. Before 

the HVAC guy gets in there and 

starts hacking up floor trusses, 

plates, and walls, let’s put some 

thought into what needs to be 

routed where. The best approach 

is to start at the initial design of 

the building, making sure that 

all of these considerations are 

accounted for when you 

are planning.” 

Kevin Brozyna, a project manager for 

IBACOS, a Building America team lead

CHAPTER 3 / BUILDING AMERICA BEST PRACTICES SERIES

3.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Traditional Versus Integrated Design Process

The Integrated Design Process loops in design input at every stage of development (Adapted from IEA 2003).

TRADITIONAL DESIGN PROCESS

➊ PROGRAMMING

➋ SCHEMATIC DESIGN

➌ DESIGN DEVELOPMENT

➎ CONSTRUCTION

 DOCUMENTATION

➐ CONSTRUCTION/COMMISSIONING

➑ ANALYZE PERFORMANCE

 TO ENSURE COMPLIANCE

➍ CONSTRUCTION

 DOCUMENTATION

➎ BIDDING & NEGOTIATION

➏ CONSTRUCTION

VALUE ENGINEERING

VALUE ENGINEERING

INTEGRATED DESIGN PROCESS

➏ BIDDING & NEGOTIATION

➊ PRE-DESIGN

➋ SET PERFORMANCE STANDARDS

➌ CONCEPTUAL DESIGN

➍ FINAL DESIGN

PERFORMANCE STANDARDS

Market Needs Incentives

Landscape

Branding

Efficiency

Energy Measures

HVAC

Moisture

Management

Sequencing

Community

Requirements

Cost

Comfort

Costs

Construction

Consideration

Advanced

Framing

HVAC Ducts

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FINAL DESIGN – Create specific drawings and system designs. 

Generate architectural, framing, HVAC, electrical, and plumbing 

drawings that specify locations for equipment chases and runs. 

Develop framing plans showing the location of every stud, floor 

truss, and roof truss. HVAC drawings should specify duct sizes 

and locations, including chases designed to carry ducts inside 

conditioned space. Some builders create a single system design 

that can be approved, installed, and warranted by any installing 

contractor on most of their home models. This can apply for many 

systems including framing, electrical, plumbing, and HVAC. 

CONSTRUCTION DOCUMENTATION – Base construction 

documents on the final design. Include statements of work for all 

subcontractors. Specify installation requirements. Use job-ready and 

job-complete checklists for self- and third-party verification.

CONSTRUCTION/COMMISSIONING – Build the houses to the 

designs. After ducts are in and sealed but before insulation and 

sheetrock are added, conduct duct leakage tests. After insulation 

is added, conduct visual inspections for compaction and voids. 

After sheetrock and wall surfaces are added, check whole-house 

air leakage, temperature evenness, room pressures, ventilation, and 

carbon monoxide levels. Confirm that specified appliances and 

lighting are installed. Use the NAHB-developed HotSpot tool to 

check and fix problem areas (see Chapter 11 for example).

ANALYZE PERFORMANCE TO ENSURE COMPLIANCE – 

Use computer models to simulate the energy consumption of your 

designs. As construction is completed, confirm performance with 

the quantitative measurements listed under commissioning above, 

including duct blaster and blower door testing using the SnapShot 

form developed by Building Science Corporation (BSC) (see Chapter 

9 for form, see Chapter 11 for description of tests) or use verification 

forms for any labeling programs you are participating in.

For More Information on Integrated Design

AIA. 2007. The Integrated Project Delivery Guide, the American Institute of Architects, 

www.aia.org/contractdocs/AIAS077630

AIA. 2010. Integrated Project Delivery: Case Studies, the American Institute of Architects, 

www.aia.org/about/initiatives/AIAB082049

ANSI. 2007. ANSI/MTS 1.0. Whole Systems Integrated Process Guide (WSIP) 2007 for 

Sustainable Buildings & Communities. Institute for Market Transformation to Sustainability. 

American National Standards Institute, http://webstore.ansi.org/RecordDetail.aspx?sku=ANS

I%2FMTS+1.0+WSIP+Guide-2007

BC Green Building Roundtable. 2007. Roadmap for the Integrated Design Process, 

Part One: Summary Guide. Prepared by Busby Perkins+Will and Stantec Consulting for 

Metro Canada. Vancouver, B.C. www.metrovancouver.org/buildsmart/design/Pages/

Integrateddesignprocess.aspx

“The biggest challenge was 

getting the subcontractors up to 

speed. IBACOS was great in their 

quality assurance, they provided 

a triple check in the field.”

Eric Jester, project manager, East Liberty 

Development, Inc., Pittsburgh

“We would do mock ups of 

some of the assemblies at 

our warehouse then have the 

contractors come to the mockup 

site so they could see what we 

were trying to achieve. If they had 

any questions or suggestions for 

how to improve the process, we 

could work those out before we 

got into the field.”

Kevin Brozyna, a project manager for 

IBACOS, a Building America team lead, 

on the East Liberty project.

CHAPTER 3 / BUILDING AMERICA BEST PRACTICES SERIES

3.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
International Energy Agency. 2003. Integrated Design Process Guideline. Prepared by 

sol*id*ar planungswerkstatt architects and engineers and Architeckten B+S for the IEA. 

www.iea-shc.org/task23/design.htm

NIBS. 2010. Engage the Integrated Design Process. National Institute of Building Sciences. 

www.wbdg.org/design/engage_process.php

Value Engineering

Value engineering has its roots in World War II. While coming 

up with creative substitutions for building supplies in the face of 

wartime shortages, staff at General Electric developed a process 

that had the unintended consequences of reducing costs and 

improving products. Value engineering has evolved into a systematic 

method for improving the value of goods and services by examining 

approaches to meeting function. Value can be increased by either 

meeting function more efficiently or reducing cost. Value engineering 

within the construction design process was developed in the 1960s.

Optimum value engineering for framing, also referred to as advanced 

framing, is one example of how value engineering can reduce 

construction costs while maintaining or improving functionality. 

More information on advanced framing can be found in Chapter 7. 

Advanced framing can be an important design feature, but value 

engineering can be applied to all aspects of home design. 

Much of Building America’s research is aimed at helping builders 

choose more efficient construction materials and methods to make 

their buildings more efficient. Building America’s research takes 

into account energy efficiency, as well as other important aspects 

of functionality, such as structural needs, durability, comfort, and 

health. Improved quality control also means fewer callbacks which 

leads to more customer referrals.

Value engineering is an important part of quality management 

and integrated design. Production builders are in a good position 

to take advantage of value engineering. The investment made up 

front in the design process pays off in the many homes where those 

improved designs are applied. Value engineering is not just about 

reducing cost, it is about selecting the systems with the best value 

and recognizing synergies within the integrated design process.

For More Information on Value Engineering

Moser, Cliff. 2007. “Using Active Value Engineering for Quality Management,” 

Practice Management Digest, American Institute of Architects. 

SAVE International. 2007. Value Standard and Body of Knowledge.

www.value-eng.org/pdf_docs/monographs/vmstd.pdf

As part of its strong commitment to quality 

assurance, Devoted Builders in Kennewick, 

WA, has 100% of its homes third-party 

tested and inspected. All homes have met 

the federal tax credit level of 50% savings 

since 2007.

“Building America showed us a 

way to take a good system and 

make it a great system.”

Eric Jester, project manager, 

East Liberty Development, Inc., 

Pittsburgh, Pennsylvania

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Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 3.9
BUILDER/DEVELOPER

PHASE #1

Decision

BUILDING SCIENCE 

PERSPECTIVE

ENGINEER / ARCHITECT / 

HERS RATER / HVAC CONTRACTOR

PHASE #2

Integrated Design

& Analysis

PHASE #4

Construction

PHASE #5

Post-Construction

Evaluation

PHASE #3

Marketing

PHASE #6

Lessons Learned

Commits to go forward with best 

practices, sets goals, and expands 

design team to include building scientists

Management evaluates costs and 

benefits and decides on next steps

Management tracks financial benefits

Management ensures proper materials 

are purchased and available

Marketers create marketing 

program to emphasize improvements

Planners integrate lessons learned in 

selection and siting of future communities

Designer evaluates changes in style 

and materials, consults code officials 

for preliminary review.

Designer adds new features 

to production plans

Site supervisors evaluate skills, 

subcontractors, and code issues

Construction documents include detailed 

plans, specifications, and scopes of work

Site supervisors train crews, set clear 

expectations, and check quality

Trades professionals implement best practices 

in their installation and construction processes

Together, trades and supervisors use 

pre-job and post-job checklists

Offers design solutions based 

on whole-building analysis, including 

materials compatibility and durability, 

and system tradeoff modeling 

Communicates design approach 

to supervisors and crew – helps 

work out installation sequences

Educates builder about building 

science and systems approach

Determines impact of design 

solutions, including energy savings

Provides test results and 

data for marketing

Observes construction practices, 

recommends improvements, 

and offers training

Offers help with upgrading 

production plans with solar 

and energy-efficient design

Conducts field tests and inspections 

including blower door, duct pressure, 

and HVAC system tests

Managing Innovation with Prototypes

Many builders choose to try out Building America technical ideas in 

a prototype house. The prototype experience enables the builder to 

experiment with new materials, products, and construction practices 

with minimal costs and risks. After building one or a few prototypes, 

the builder decides which features to carry forward into standard 

construction. The chart below shows a process for working with building 

scientists, such as a Building America team, a HERS rater, engineer, 

architect, or trained staff member to build the prototype house.

Rural Development, Inc. (RDI) worked with Building America’s 

CARB team in 2006 on the development of a prototype home in 

Colrain, Massachusetts, that achieved a HERS score of 21. RDI 

used that experience to design 20 multi-family units in Turners Falls 

that achieved HERS scores of 8 to 18.

Process for Building a Prototype 

High-Performance Home

S&A Homes, who worked with Building 

America on six above-market-rate homes 

in Pittsburgh, decided to push the envelope 

by building a prototype zero-energy home 

with Building America team lead IBACOS 

providing technical support.

“The zero-energy lab house [which 

S&A Homes is constructing with 

IBACOS] is a great project. We 

skipped over 50% and 60% and 

went right to zero energy. The lab 

home pushes us even further into 

tomorrow so we understand now 

what we will need to do to stay 

ahead of the code even 10 or 15 

years from now.”

Todd Winnor, project manager, 

S&A Homes, Pittsburgh, Pennsylvania

“The next community I want to 

do totally BuiltGreen, including 

the street layout, infrastructure, 

etc., with all Building Americalevel ENERGY STAR and 

BuiltGreen homes. My goal is 

to build zero energy houses. 

Hopefully we can get closer and 

closer to that, and do it sensibly.”

Fred Giacci, owner of Devoted Builders, 

Kennewick, Washington

CHAPTER 3 / BUILDING AMERICA BEST PRACTICES SERIES

3.10 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
The number one reason builders give for building energy-efficient homes 

is to differentiate their product from their competitors, (NAHBRC 

2007)—and it works. Building America has worked with hundreds of 

builders who have successfully used energy efficiency to sell houses. 

Consumers want the value and comfort high-performance homes offer. 

Builders want happy customers and the positive referrals they will give. 

However, the sales do not happen by themselves. To recoup the 

investment builders make in energy efficiency and quality management, 

they should do the following:

•	 Brand and label their products for fast and easy differentiation. 

•	 Train their sales staff to educate consumers.

•	 Market the sometimes hidden energy-efficient features of the home.

•	 Get their business name and products in front of the public.

Branding and Labeling

Branding and labeling offer two methods for gaining consumer 

attention and confidence. When consumers recognize a brand and 

associate that brand with positive attributes, they are more willing 

to consider purchasing that product. 

Creating a recognizable brand that resonates with consumers is 

difficult. Large corporations that rely on consumer sales spend 

millions of dollars on campaigns to keep their brands fresh but 

familiar. This investment pays off best when products involve 

multiple, frequent purchases from many consumers. Most builders 

do not fit this equation very well—builders typically sell their 

products in limited markets, and homebuyers tend to hang onto 

their purchases for a long time.

Chapter 4.

Selling Performance

Energy efficiency and low maintenance are a 

winning combination for Devoted Builders of 

Kennewick, Washington. 

“Real estate is perception. These 

homes gave a very strong perception 

that this was a good idea.” 

Eric Jester, project manager, 

East Liberty Development, Inc.

For S&A Homes and East Liberty 

Development Inc., energy efficiency has 

not only sold homes, it has helped sell 

the neighborhood. In a part of Pittsburgh 

where homes were typically selling for 

under $50,000, S&A’s six highly efficient 

homes sold for $200,000 to $300,000.

CHAPTER TOPICS

4.1 Branding and Labeling

4.3 Training Sales Staff

4.5 Marketing Energy Efficiency

4.6 Reaching Out to the Media

R

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CHAPTER 4. SELLING PERFORMANCE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 4.1
Brands like Builders Challenge, ENERGY STAR, and other national 

and regional programs offer builders a recognizable label tied to 

known sets of standards. Qualifying for these nationally known 

programs will give your energy-efficiency efforts instant credibility, 

and they are excellent vehicles for leveraging your marketing dollars. 

Homes that achieve a 70 or lower on the HERS Index and that meet 

specified quality criteria can qualify for DOE’s Builders Challenge. 

The Builders Challenge label shown below is attached to qualifying 

homes. In addition to identifying the Builders Challenge brand, 

the label also provides useful information for consumers. The label 

incorporates the E-Scale, a ranking of energy efficiency based on 

the HERS index. Like a miles-per-gallon rating, this index gives 

consumers an easy way to compare and distinguish competing houses. 

The ENERGY STAR logo is a label that most consumers recognize 

for products that are energy efficient and good for the environment. 

This label can be found on many consumer products ranging from 

computers and dishwashers to lights and homes. Homes that qualify 

for the ENERGY STAR for Homes label are generally about 15% 

more energy efficient than the 2006 IECC requirements. Whether 

or not builders choose to brand their homes as ENERGY STAR 

homes, many of the products that go into the home (or are on display 

in model homes) can carry the ENERGY STAR logo. 

“Many builders out there have 

their own energy-efficiency 

programs, and each one is called 

something different. The U.S. 

Department of Energy is known 

and respected. It lends credibility 

if you can say you are meeting 

the DOE’s Builders Challenge 

standard, as opposed to meeting 

a program criteria you came up 

with yourself.”

Chris Kelly, vice president of operations, 

Pulte Phoenix Division

U.S. Department of Energy 

Builders Challenge 

DOE has posed a challenge to the 

homebuilding industry—to make costeffective, highly energy-efficient homes 

available to all Americans by 2030. 

As of September 2010, 623 builders 

have participated in Builders Challenge, 

qualifying more than 3,700 homes. 

Homes are achieving average 

HERS scores of 63 and saving their 

homeowners on average $873 per 

home per year in energy cost savings.

Meets The Builders Challenge

Recognizing the best energy performance, quality, comfort, health, and safety in the market.

Conditioned floor area (sq. ft.): 3,312

SM

Estimated average 

monthly energy bill:

$104

Estimated annual energy usage:

Electric (kWh) 7728

Natural gas (Therms) 237

123 Main Street, Gainesville, FL 32601

Rated by Home Performance, Inc.

Rating conducted June 8, 2008

www.buildingamerica.gov/challenge

64

Your Home!

ADBuilder ADBuilder

#00000000000

Maximized

Energy-Efficient

Home

R

CHAPTER 4 / BUILDING AMERICA BEST PRACTICES SERIES

4.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Both the ENERGY STAR (www.energystar.gov) and the Builders 

Challenge (www.buildingamerica.gov/challenge) websites provide 

brochures and materials that builders can download for marketing. 

DOE’s Builders Challenge has formed national partnerships with 

other green building programs that provide marketing and labeling 

support, including the National Association of Home Builders’ 

National Green Building ProgramTM (NAHB 2009), the U.S. Green 

Building Council’s Leadership in Energy and Environmental Design 

(LEED) for Homes program, and Masco’s Environments for Living®. 

Many Building America builders choose to offer their homeowners 

an energy-use guarantee. Some builders do this on their own; others 

work through Masco Home Service’s Environments for Living 

program. Masco developed the program in 2001 with help from 

Advanced Energy Corporation and Building Science Corporation, 

a Building America team lead. Under Environments for Living, the 

home’s heating and cooling energy use are estimated, and Masco 

guarantees the homeowner that Masco will pay them the difference 

if their energy bills are higher than the calculated estimate.

For homes at the Environments for Living gold and platinum level, 

Masco also offers a comfort guarantee promising the temperature at the 

thermostat will not vary more than three degrees from the temperature 

at the center of any conditioned room within that thermostat zone. The 

gold level requires that homes perform 15% above code (2006 IECC) 

and qualify for the U.S. EPA’s ENERGY STAR® label. The platinum 

level requires that homes perform 30% above IECC and qualify for the 

U.S. DOE’s Builders Challenge program.

Training Sales Staff 

Having properly trained sales staff is key to helping buyers 

understand and appreciate the value of energy-efficiency features. 

As the first builder to qualify homes for the Builders Challenge in 

California, the Grupe Company realized the importance of training. 

Grupe’s approach to training involved the entire staff. Tools were 

developed for the sales team that included a technical sales resource 

binder, four hours of initial formal training, and ongoing training 

sessions. Training covered financial benefits for homeowners, solar 

power for homes, energy-efficiency features, and utility information. 

Another Building America builder, Vern McKown, co-owner of Ideal 

Homes in Norman, Oklahoma, shared some of his tips for training 

and marketing at the Energy and Environmental Building Alliance 

(EEBA) National Conference in Denver, Colorado, in September 2009: 

Builders who meet the DOE Builders 

Challenge criteria also qualify for the 

Environments for Living platinum level.

ENERGY STAR Update

In April 2010, the U.S. Environmental 

Protection Agency (EPA) announced 

new, more rigorous guidelines known as 

ENERGY STAR for New Homes Version 

3.0. The updated requirements will ensure 

that the government’s ENERGY STAR label 

continues to deliver a significant increase 

in energy efficiency over homes that are 

built to code and standard builder business 

practices. Homes that earn the ENERGY 

STAR label under Version 3.0 will show 

energy savings of 15% compared to homes 

built to the 2009 IECC. These guidelines 

are being phased in during 2011 and, on 

January 1, 2012, will become effective for 

all homes permitted on or after that date.

For more information about ENERGY STAR 

for Homes, see: www.energystar.gov

4.3

CHAPTER 4. SELLING PERFORMANCE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 4.3
 TRAIN SALES STAFF.

- Field training of every sales person every six months, no matter how 

long they’ve been with the company.

- New hire sales training boot camp.

 GIVE SALES STAFF SIMPLE MESSAGES TO CONVEY, 

 FOR EXAMPLE:

- Here’s how we are different—show infrared camera photos.

- Blown-in insulation fills in nooks and crannies better than batt.

- Our duct leakage is 5%, the average is 27%.

- Our windows are high performance—less heat in, less energy loss out.

- Utilities are guaranteed.

 GET SALES STAFF TO WALK BUYERS THROUGH THE HOME.

- Identify four key exterior features and nine key interior features.

- Use mystery shoppers to find out what your sales folks are actually 

telling shoppers. 

- Keep it simple—“We tell sales folks, if you aren’t sure of the specifics 

just say ‘we’re better’ and stop there.”

 STAFF YOUR WEBSITE.

- Keep your website up to date.

- Make it active with a phone or email link to a live person.

- Respond to web inquiries within five minutes.

- When the typical customer looks at the website, they look at the 

location, street scene, elevation, and floor plan.

- Ideal Homes trains its sales staff to interrupt that typical thought 

process, to emphasize that “we are different and we are better,” by 

pointing out energy savings and quality.

 FIND A NICHE.

- “We have a competitor 1.5 miles away who is a national builder. They 

sell at 78 cents/ft2, we sell at $1.12/ft2. We have a different market 

niche,” said McKown.

- All of Ideal’s homes are Builders Challenge homes.

 DO YOUR OWN RESEARCH.

- Do exit interviews with customers, buyers, and lookers.

- Drill down for specifics in problem areas.

- Have every trade fill out job-ready and job-complete forms.

- Do NAHB quality certification audits of the whole company on 

a regular basis.

 ENSURE CULTURAL AND CORPORATE ALIGNMENT.

- Identify your company’s core values and hire people who share those values. 

- Ask your employees where the weak spots are and fix them. 

- Ask your employees how you can help them do their jobs better.

“It’s a matter of education. We 

sell a lot of homes to engineers, 

they are all over our product. 

But the general public needs 

more education on the value of 

energy efficiency. They need to 

understand, your home is worth 

more. It will be more comfortable 

and more easy to maintain. It’s 

healthier. You’ll save energy. Your 

utility bills are going to be lower.”

Fred Giacci, owner, Devoted Builders, 

Kennewick, Washington

Field train sales staff every six months 

to keep them up to date on energyefficiency techniques.

CHAPTER 4 / BUILDING AMERICA BEST PRACTICES SERIES

4.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Marketing Energy Efficiency

A challenge for builders of energy-efficient homes is showing 

consumers the energy efficiency they are purchasing. Most energyefficiency improvements are hidden away in walls and attics invisible 

to buying eyes. Making energy improvements “real” to the consumer 

is a multi-faceted, ongoing process that can include any of the 

following (NAHBRC 2010):

•	 Emphasize cost, comfort, health, and environmental benefits. 

•	 Educate customers and sales professionals. Use duct blaster, 

blower door, and HERS scores to show differences.

•	 Use walk-throughs and model homes with display cutaways of energy 

features such as insulated attics and wall sections to help buyers and 

sales staff understand the energy-efficient construction process.

•	 Turn the model home’s garage into an energy information center. 

Use side-by-side displays on walls, demo walls showing wall and 

window features, touch screen videos, and poster board displays.

•	 Organize tours for homebuyers, school groups, media, and 

realtors. Use slides, sample products, and energy bills as aids.

•	 Emphasize an energy-efficiency upgrade when signing the final 

papers. One builder has a wall of testimonials, photos, and examples 

of utility bills in his waiting room. Another builder has the buyer 

meet with the building site supervisor after the sale is made for one 

more chance to sign up for energy-efficiency upgrades. 

•	 Provide take-home brochures that explain energy-saving features. 

Develop your own fact sheets or give away Building America 

and ENERGY STAR brochures, reprints of magazine articles, 

and vendor and trade association brochures. Also, give potential 

buyers a checklist so they can compare the energy-saving measures 

in your homes with those of other builders (see Appendix I). 

•	 Use paid advertising with a simple slogan. One builder created an ad 

campaign based on “$60,” a figure they guaranteed monthly electric 

bills would not exceed for the first year. They ran ads on billboards, 

the sides of buses, signs on their property, and in the newspaper. 

•	 Use the Internet—websites, YouTube videos, Facebook, Twitter, etc. 

•	 Seek out free publicity, send out press releases, hold media events. 

•	 Participate in building-related charity events.

•	 Get involved in your local home builders association.

•	 Offer energy-efficiency guarantees. 

•	 Make buyers aware of energy-efficient mortgages.

(top) Show potential buyers your 

energy-efficient features with cut-aways 

and side-by-side displays.

(bottom) Use signage to spell out 

your message.

Through 2009, Building America builders 

have won 93 Energy Value Housing Awards 

(EVHA) from the National Association of 

Home Builders Research Center. Beginning 

with the 2010 awards 

cycle, builders can earn 

points for participation in 

DOE’s Builders Challenge 

program and can apply 

for Builders Challenge 

certification through the 

EVHA application process.

“Now we have a marketing 

advantage. We are looked at as 

one of the experts in the industry 

in terms of energy efficiency.”

Chris Nelson, president of Nelson 

Construction, Farmington, Connecticut

4.5

CHAPTER 4. SELLING PERFORMANCE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 4.5
•	 Package energy efficiency features through a national or regional 

program or your company’s own energy-efficiency “brand.”

Reaching Out to the Media

Nothing is more cost effective than sending out a news release to local 

media to announce business news and other company activities. News 

related to energy efficiency can include partnering with the Builders 

Challenge, reaching a new best score for your area on the HERS 

Index, hitting milestones in numbers of energy-efficient houses built, 

winning awards for energy-efficient and green construction, trying 

out new technologies, offering tours of houses under construction, 

or cooperating with research organizations such as colleges or DOE. 

News releases can cover your company’s involvement in educational 

and charitable activities, for example, teaching school children about 

energy efficiency or building homes with Habitat for Humanity. 

Companies that try out new technologies or apply technologies 

on a big scale have earned much in the way of media exposure. 

For example, builders who have installed photovoltaic systems 

have been reported in The New York Times, on major televisions 

networks, and in the local press.

For More Information on Marketing

Builders Challenge www.buildingamerica.gov/challenge

ENERGY STAR www.energystar.gov

Environments for Living www.environmentsforliving.com

Farnsworth, Christina. 2003. “The Weakest Link.” Builder Magazine, December 2003, 

http://www.builderonline.com/business/the-weakest-link.aspx?printerfriendly=true

NAHB. 2009. ICC 700-2008 National Green Building Standard, the National Association of 

Home Builders and the International Codes Council, www.nahb.org

NAHBRC. 2007. Building America Challenge Survey of Builders and Consumers. Proprietary 

survey commissioned by DOE and conducted by the NAHBRC as part of the Annual 

Consumer Practices Survey. National Association of Home Builders Research Center, 

Upper Marlboro, MD.

NAHBRC. 2009. Green Building Program. National Association of Home Builders 

Research Center, www.nahbgreen.org

NAHBRC. 2010. Energy Value Housing Award Program. National Association of Home 

Builders Research Center, www.nahbrc.org/EVHA

Sikora, Jeannie. 2002. Energy Value Housing Award Guide: How To Build and Profit with 

Energy Efficiency in New Home Construction. National Association of Home Builders 

Research Center, Upper Marlboro, MD. www.nahbrc.org

U.S. Environmental Protection Agency. EPA Indoor airPLUS labeling program for new 

homes, www.epa.gov/indoorairplus/about.html

U.S. Environmental Protection Agency. WaterSense: An EPA Partnership Program, New 

Homes, “Saving Water—Inside and Out,” www.epa.gov/watersense/pp/new_homes.htm

U.S. Green Building Council www.usgbc.org

East Liberty Development, Inc., 

promoted its new homes in a historic 

neighborhood of Pittsburgh with a 

ribbon-cutting ceremony attended by 

Pittsburgh’s mayor, a congressional 

representative, the director of the 

Urban Renewal Authority, other elected 

officials, members of the press, and 

interested homebuyers in attendance. 

The New York Times and several regional 

news outlets picked up the story.

CHAPTER 4 / BUILDING AMERICA BEST PRACTICES SERIES

4.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Building America builder, New Tradition 

Homes of Washington State has its own 

channel on YouTube with over a dozen video 

clips advertising its energy-efficiency features. 

www.youtube.com/user/NewTraditionHomes

4.7

CHAPTER 4. SELLING PERFORMANCE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 4.7
East Liberty Development, Inc., 

modified a Builders Challenge 

label to show the annual utility 

bills homebuyers can expect 

from one of its energy-efficient 

homes compared to utility bills 

from three typical existing local 

homes, a new code-built home, 

and an ENERGY STAR home.

CHAPTER 4 / BUILDING AMERICA BEST PRACTICES SERIES

4.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
There are 34 states that are wholly or partially in the cold or very 

cold Building America climates. Conditions vary widely across these 

climate zones, which stretch from Alaska to Arizona and California 

to Rhode Island. 

Builders in the cold climate must be able to address solar gains in 

the summer and extreme, prolonged low temperatures and snow 

accumulation in the winter, along with torrential downpours, 

high winds, and, especially in areas east of the Mississippi, high 

humidity. The recommendations in this Best Practices guide apply 

to the cold and very cold climate regions. If you aren’t sure that 

your project is within these climate regions, check the Building 

America Best Practices Volume 7.1 Guide to Determining Climate 

Regions by County (DOE 2010, www.buildingamerica.gov) for a 

list of counties and climate zones. The Building America cold/

very cold climate zones correspond to the International Energy 

Conservation Code (IECC) climate zones 5, 6, and 7 (Briggs et al. 

2003; see maps page 5.3).

In addition to describing the cold and very cold climates, this 

chapter also provides information on building in the extreme 

weather conditions that can occur in these climates including heavy 

precipitation, high winds and tornadoes, flooding, earthquakes, and 

forest fires. Siting and design considerations with respect to solar 

gain are also included. See Chapters 7 and 8 for information on 

moisture management, air sealing, and thermal control techniques 

for foundations, walls, and roofs.

Chapter 5.

The Cold and 

Very Cold Climates

“Building America achieves 

superior performance by applying 

measures that work with the 

local climate. The principles that 

go into the design of Building 

America houses are sophisticated 

but not complicated. I would 

encourage any builder who is 

interested in near zero-energy 

construction to talk to us and 

give it a try.” 

George James, manager, new construction 

program, U.S. Department of Energy 

Building America

CHAPTER TOPICS

5.2 Design Considerations 

for Cold Climates

5.2 Climate Description

5.5 Weather 

5.10 Considering Solar Gain

in Siting and Design

5.1

CHAPTER 5. THE COLD & VERY COLD CLIMATES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 5.1
Design Considerations for Cold Climates

The extreme temperature variations, forces of driving wind and rain, 

snow accumulation and melting can take their toll on buildings and 

contribute to premature aging. Based on work with its cold climate case 

study builders, Building America makes the following recommendations 

for designing homes in the cold and very cold climate zones where 

high snow accumulation is likely:

•	 Don’t put balconies, stairs, parking, or entrances under eaves. 

•	 Design to avoid ice dams. Place any necessary roof penetrations 

high toward the ridge. 

•	 Avoid electric snowmelt systems in roofs.

•	 Avoid use of gutters in high snow load locations.

•	 Orient buildings to allow for southern exposure to entrances, 

drives, and walks to encourage snow and ice melting and reduce 

the need for snow and ice removal and snow storage.

•	 Protect entrances and sidewalks by locating them under overhangs 

or at gable ends. 

•	 Anticipate wind direction and drifting.

•	 Use low-maintenance, high-durability exterior products – for 

example cement fiber board siding, composite decking materials, 

and stained cedar railings. 

•	 Keep furnaces and ducts out of attics and air seal ceiling lid well to 

lessen likelihood of ice dam formation. 

•	 Heat and insulate basements and crawlspaces.

•	 Place footings below frost depth.

Climate Description

Cold

A cold climate is defined as a region with between 5,400 and 9,000 

heating degree days (65°F basis). The Building America cold climate 

corresponds to the IECC climate zones 5 and 6.

Very Cold

A very cold climate is defined as a region with between 9,000 and 

12,600 heating degree days (65°F basis). The Building America very 

cold climate corresponds to IECC climate zone 7.

FEMA Fact Sheets

The Federal Emergency Management 

Agency (FEMA) has produced a series of 31 

fact sheets providing recommendations for 

building homes in high wind and rain areas. 

The guides cover siting recommendations; 

moisture barrier systems; housewrap, 

masonry, roof sheathing, and other 

building materials; door and window 

installation; roof and deck-to-wall flashing; 

tile and asphalt roofing techniques for high 

wind areas; foundations; and construction 

techniques in flood-prone areas. See www.

fema.gov/library/viewRecord.do?id=1570. 

For More Information 

on Climate Description 

Briggs, RS; RG Lucas; and ZT 

Taylor. 2003. “Climate Classification 

for Building Energy Codes and 

Standards: Part 2 - Zone Definitions, 

Maps and Comparisons,” Technical and 

Symposium Papers, ASHRAE Winter 

Meeting, Chicago, January 2003.

DOE. 2010. Vol. 7.1: Guide to Determining 

Climate Regions by County. PNNL-19517, 

Building America Best Practices Series, 

Prepared for the U.S. Department of 

Energy by Pacific Northwest National 

Laboratory, www.buildingamerica.gov

NOAA. 2010. National Climatic Data 

Center. www.climate.gov/#dataServices/

pastPresent

CHAPTER 5 / BUILDING AMERICA BEST PRACTICES SERIES

5.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Subarctic

A subarctic climate is defined as a region with 12,600 heating degree 

days (65° basis) or more. The only subarctic regions in the United 

States are found in Alaska, which is not shown on the climate maps 

below. The Building America subarctic climate zone corresponds to 

IECC climate zone 8. While some of the guidelines in this document 

would apply to construction in the subarctic, the subarctic climate has 

its own unique considerations, which are not addressed in this guide.

HOT-HUMID

MIXED-HUMID

COLD / VERY COLD

HOT-DRY / MIXED-DRY

MARINE

1

2 2

2 3

3

4

4

5 5

6

6

7

Marine (C)

Dry (B) Moist (A)

All of Alaska in Zone 7

except for the following

Boroughs in Zone 8:

Bethel

Dellingham

Fairbanks N. Star

Nome

North Slope

Northwest Arctic

Southeast Fairbanks

Wade Hampton

Yukon−Koyukuk

Zone 1 includes

Hawaii, Guam,

Puerto Rico,

and the Virgin Islands

Warm−Humid

Below White Line

Building America 

U.S. Climate Regions

International Energy 

Conservation Code Map

The Building America cold 

and very cold climate regions 

correspond to zones designated 

5, 6, and 7 on the International 

Energy Conservation Code map. 

The Building America subarctic 

climate corresponds to IECC 

climate zone 8, which occurs 

only in Alaska and does not 

appear on this map.

5.3

CHAPTER 5. THE COLD & VERY COLD CLIMATES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 5.3
Mississippi River

Mississippi River

Missouri

River

Missouri

River

Rio Grande

Rio

Grande

Arkansas

River

Colorado

River

Ohio

River

Red

River

Brazos River

Columbia

River

Snake

R

Platte

R

Pecos River

Canadian

River

Tennessee

River

Colorado

River

Alabama

R

Kansas River

Republican

R

Lake of the Woods

Great Salt Lake

Lake Okeechobee

Lake Pontchartrain

Lake Champlain

Lake St Clair

Red Lake

Salton Sea

Rainy Lake

Lake Winnebago

Mille Lacs Lake

Yellowston e R

R Gila

River

N Platte R

S Platte

R

James

River

Red R

Illinois R

River

Cumberland

Savannah R

St Johns R

James R

Su qs uehanna

R

Connecticut R

Sacramento R

Green

Kennebec R

Hudson River

Scioto R

Wabash River

Oconee R

Des Moines R

Humboldt R

Willamette R

G U L F O F M E X I C O

P A

C I F I C

O

C

E

A

N

A

T

L

A

N

T I C

O

C

E

A

N

Lake Superior

Lake Michigan

Lake Huron

La k e Eri e

O n t a ri o

La k e

MAINE

VERMONT

NEW HAMPSHIRE NEW YORK MASSACHUSETTS

CONNECTICUT

RHODE ISLAND

PENNSYLVANIA

NEW JERSEY

DELAWARE

MARYLAND

VIRGINIA

WEST VIRGINIA

OHIO

INDIANA ILLINOIS

WISCONSIN

KENTUCKY

TENNESSEE NORTH CAROLINA

SOUTH

CAROLINA GEORGIA ALABAMA

FLORIDA

MISSISSIPPI

LOUISIANA

TEXAS

ARKANSAS

MISSOURI

IOWA

MINNESOTA

NORTH DAKOTA

SOUTH DAKOTA

NEBRASKA

KANSAS

OKLAHOMA

NEW MEXICO

COLORADO

WYOMING

MONTANA

IDAHO

UTAH

ARIZONA

NEVADA

CALIFORNIA

OREGON

WASHINGTON

DC

M I C H I G A N

The National Atlas of the United States of America U.S. Department of the Interior

U.S. Geological Survey

Where We Are nationalatlas.gov TM

OR

pageprecip_us3.pdf INTERIOR-GEOLOGICAL SURVEY, RESTON, VIRGINIA-2005

PACIFIC OCEAN

ATLANT I C O CE A N

HAWAII

ALASKA

M E X I C O

C A N A D A

C U B A

T H E B A H A M A

0 300 mi S

0 100 200 300 km

100 200

Albers equal area projection

PRECIPITATION

180.1-200

140.1-180

120.1-140

100.1-120

80.1-100

70.1-80

60.1-70

50.1-60

40.1-50

35.1-40

30.1-35

25.1-30

20.1-25

15.1-20

10.1-15

5.1-10

5 and less

Average Annual Precipitation (in inches)

1961-1990

Precipitation varies widely across the

United States, from a low of 2.3 inches

per year in California's Death Valley to a

high of 460 inches on Hawaii's Mount

Waialeale. Nevada ranks as the driest

state, with an average annual

precipitation of 9.5 inches, and Hawaii

is the wettest, at 70.3 inches.

Average Annual Precipitation 

(Source: U.S. Geological Survey)

Mean Annual U.S. Snowfall 

(Source: Environmental 

Science Services Administration)

0.0

0.1 - 3.0

3.1 - 6.0

6.1 - 12.0

12.1 - 24.0

24.1 - 36.0

38.1 - 48.0

48.1 - 72.0

> 72.0

Mean total snowfall 

(inches)

Average Annual Precipitation (1961-1990) (inches)

180.1 - 200

140.1 - 180

120.1 - 140

100.1 - 120

80.1 - 100

70.1 - 80

60.1 - 70

50.1 - 60 

40.1 - 50

35.1 - 40

30.1 - 35

25.1 - 30

20.5 - 25

15.1 - 20

10.1 - 15

5.1 - 10

5 and less

CHAPTER 5 / BUILDING AMERICA BEST PRACTICES SERIES

5.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Weather

Portions of the cold climate are subject to frequent and intense rain 

and snow storms, severe thunderstorms, and hail. Some areas are 

at high risk for tornadoes and high winds. Large portions of the 

Midwest and Northeast have been subject to flooding, with most of 

the counties of these areas experiencing four or more presidential 

disaster declarations due to flooding since 1965.

The region is at low risk of earthquakes except for localized areas 

in Idaho, Wyoming, and Utah and at the border of Tennessee and 

Missouri. The cold and very cold climate zones are at low risk 

of volcanic eruption except in Alaska, Washington, and Oregon. 

Portions of the cold climate are prone to landslides, especially in the 

Rocky Mountains and Appalachian Mountains. The region is at low 

risk for hurricanes except along the Eastern seaboard (USGS 2010).

Precipitation

Cold climate states in the southwest and Great Plains are the 

driest in the United States, experiencing less than 20 inches of 

precipitation per year, while cold states in the Northwest, Midwest, 

and Northeast commonly experience annual precipitation levels of 

40 inches or more. Construction techniques for snow and moisture 

management are described in Chapter 8. 

For More Information on Weather and Precipitation

National Climatic Data Center. 2005. Climate Maps of the United States. National Oceanic and 

Atmospheric Administration (NOAA) http://hurricane.ncdc.noaa.gov/cgi-bin/climaps/climaps.pl

U.S. Geological Survey. 2005. “The National Atlas of the United States of America: 

Precipitation,” U.S. Department of the Interior, www.nationalatlas.gov.

U.S. Geological Survey. 2010. “Natural Disasters,” www.usgs.gov/hazards/

Flooding

Flooding is a concern along inland waterways of the cold climate. 

Large portions of the Midwest and Northeast have been subject to 

flooding, with most of the counties of these areas experiencing four 

or more presidential disaster declarations due to flooding since 1965. 

Builders should check state building codes and contact the local 

community floodplain administrator for information on local floodplain 

management regulations. Location-specific Flood Insurance Rate Maps 

(FIRMs) can be obtained at www.fema.gov/hazard/map/firm.shtm.

If a community adopts and enforces adequate floodplain 

management regulations, FEMA will make flood insurance available 

within the community. Title 44 of the U.S. Code of Federal 

Regulations (CFR) contains the National Flood Insurance Program 

(top) Large-scale floods have hit the 

midwest repeatedly in recent decades 

(Photo source: USGS)

(middle) S&A Homes practices good 

water runoff management to control 

sediment during construction and to 

ensure that stormwater drains away 

from the house after construction.

(bottom) Vegetated swales, pervious 

pavers, pocket parks, and retention 

of existing trees all help to minimize 

runoff and lessen impacts on municipal 

sewer systems.

5.5

CHAPTER 5. THE COLD & VERY COLD CLIMATES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 5.5
(NFIP) criteria for floodplain management, including design and 

construction standards for new and substantially improved buildings 

located in special flood hazard areas (SFHAs) identified on the 

NFIP’s Flood Insurance Rate Maps (FIRMs). An SFHA is an area 

that has 1% chance of being flooded in a given year. [CFR Title 44, 

Section 60.3(a)(3) requires that all new construction in a flood-prone 

area be constructed with materials resistant to flood damage.] The 

lowest floor of a residential building must be elevated to or above 

the base flood elevation (BFE). All construction below the BFE is 

susceptible to flooding and must consist of flood damage-resistant 

building materials, for example brick; cement board; concrete; 

non-paper faced gypsum; steel or solid-wood preservative-treated 

studs, trusses, and joists; and ceramic tile. Flood-resistant materials 

are described in “Flood Damage-Resistant Materials Requirements,”

one of a series of Technical Bulletins that FEMA has produced to 

provide guidance concerning the building performance requirements 

of the NFIP (available at www.fema.gov/plan/prevent/floodplain/

techbul.shtm). [Code requirements for flood-resistant construction are 

detailed in the 2009 IRC R322.]

“FEMA reports that up to 25% of NFIP flood insurance claims are 

paid on buildings that are outside of the mapped SFHA. This occurs 

for many reasons, including out-of-date maps and local drainage 

problems” (FEMA 2008); therefore, all builders should be aware of 

flood-safe construction practices, regardless of location designation. 

Joseph Lstiburek of Building Science Corporation, a Building 

America team lead, recommends three basic strategies for building 

in flood-prone areas: elevate structures, build with materials that 

can get wet, and design assemblies to easily dry when they get wet. 

Specific recommendations include building the first floor using 

non-water-sensitive materials such as masonry, using an elevated slab 

or raising the crawlspace floor above grade, and using rigid foam 

exterior insulation such as rigid fiberglass rather than batt cavity 

insulation (especially on basement and first-floor walls).

For More Information on Construction in Flood Zones

Algan, H. and Wendt, R. 2005. Pre-Standard Development for the Testing of Flood-DamageResistant Residential Envelope Systems, Comparison of Field and Laboratory Results - 

Summary Report, Oak Ridge National Laboratory.

FEMA. 2000. Coastal Construction Manual, Third Edition, FEMA-55, Federal Emergency 

Management Agency, Washington, D.C., www.fema.gov

FEMA. 2008. Flood Damage-Resistant Materials Requirements for buildings located in 

special flood hazard areas in accordance with the National Flood Insurance Program, 

August 2008, FEMA Technical Bulletin, Federal Emergency Management Agency, 

www.fema.gov/library/viewRecord.do?id=1580

Lstiburek, Joseph. 2006. Flood and Hurricane Resistant Buildings, Building Science Digest 111, 

Building Science Press, www.buildingscience.com

Extreme Climate

The cold and very cold climates include 

some of the driest states (New Mexico, 

Utah, Nevada) and some of the wettest 

(Michigan, New York, West Virginia) 

as well as some of the most tornadoprone (Iowa, Illinois, Indiana); hail-prone 

(Colorado, Kansas), and windiest states 

(Massachusetts, Minnesota, Wyoming). 

And, of course, the top ten snowiest and 

top 10 coldest U.S. cities are located in the 

cold and very cold climates. Conditions can 

vary significantly from season to season 

within these states. The ten U.S. cities with 

the largest variation in average seasonal 

temperature from summer to winter are 

all cold climate cities, with variations 

of up to 91 degrees between average 

summer and average winter temperatures. 

Some locations experience dramatic 

temperatures swings even within a single 

day – swings of 60, 80, and even 100 

degrees have been known to occur. 

(NOAA 2010).

CHAPTER 5 / BUILDING AMERICA BEST PRACTICES SERIES

5.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Stormwater Management 

Builders are increasingly being called upon to manage surface runoff 

water onsite during and after construction because stormwater 

runoff carries with it sediment and pollutants that negatively impact 

water quality and high levels of runoff tax municipal sewer systems. 

Builders should check local requirements and guidelines regarding 

site water runoff control during and after construction. For long-term 

stormwater management, builders can minimize impervious surface 

areas by designing smaller building footprints, clustering developments, 

and adding green space areas; installing onsite rain-water harvesting 

systems; and using pervious paver materials. Other recommendations 

include planting vegetated buffers around parking areas; planting 

new trees and shrubs and retaining existing trees to minimize erosion; 

constructing swales, drywells, soakage trenches, planter boxes, 

vegetated infiltration basins, and flow-through planters; and installing 

drywells under streets to handle overflow from large storm events. 

Tornadoes and High Winds 

The cold climate includes areas in wind zone 4 (the highest risk zone) 

on FEMA’s scale of four U.S. wind zones, as well as areas designated 

special wind regions and hurricane-susceptible regions. FEMA, 

the NAHBRC, and the U.S. Department of Housing and Urban 

Development (HUD) have put together guidelines for constructing 

asphalt and tile roofs in high-wind coastal areas www.fema.gov/

library/viewRecord.do?id=1570. The Institute for Business and Home 

Safety provides structural details and guidance and a list of building 

materials acceptable for high-wind areas at www.disastersafety.org. 

For More Information About 

Stormwater Management

EPA. 2010. Stormwater Program. U.S. 

Environmental Protection Agency. http://cfpub.

epa.gov/npdes/home.cfm?program_id=6

Shaw, Daniel, Rusty Schmidt, Brian Ashman, 

Hugh Johnson, and Tony Randazzo. Plants for 

Stormwater Design, Volume II, Species Selection 

for the Upper Midwest, Great River Greening, 

St. Paul, Minnesota.

City of Portland. 2010. Stormwater Solutions 

Handbook, Bureau of Environmental Services, 

www.portlandonline.com/bes/index.

cfm?c=43110

City of Cleveland. 2004. Guidance Document: 

Erosion and Sediment Control Best Management 

Practices for Home Builders, Cleveland, 

Tennessee.

NAHB. 2010. “Citing Flawed Analysis, Feds 

Send EPA Storm Water Rules Back to the 

Drawing Board,” National Association of Home 

Builders press release, August 13, 2010 

www.nahb.com/news_details.

aspx?sectionID=479&newsID=11185

4 or more declarations

3 declarations

2 declarations

1 declaration

Map shows presidential disaster 

declaration for flooding by 

county 1965-2003:

Flooding in the 

United States

(Source: FEMA, Michael Baker Jr., Inc., 

the National Atlas and the USGS)

5.7

CHAPTER 5. THE COLD & VERY COLD CLIMATES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 5.7
New requirements in the 2009 IRC R301 address some of these highwind concerns with increased wall bracing requirements for homes 

built in high-wind and high-seismic actvity areas. The new code 

increases the amount of wall bracing needed to resist wind loads 

for three-story homes, homes with large open plans, and homes 

in high-wind regions. In addition, the new code requires blocking 

between the roof framing members at braced wall panels for homes 

with deep truss members or roof joists, or homes in high-wind 

and high-seismic areas. The new requirements include prescriptive 

blocking details for these conditions. These changes may require 

revisions to stock plans and standard detailing practices.

For builders and homeowners in tornado-prone areas, FEMA has 

prepared a guide for building safe rooms—rooms with reinforced walls 

where occupants can safely take shelter during a tornado or hurricane.

Seismic Events 

Portions of the cold climate region, including areas in and around 

Idaho, Wyoming, Illinois, New York, and Alaska, are in seismic 

design categories C, D, and E. Construction in these areas must follow 

the requirements of the 2009 IRC, which addresses seismic provisions in 

R301.2.2. Information on design and construction in earthquakeprone areas—including above-code recommendations; detailed 

figures for foundations and foundation walls, floor construction, walls, 

roof-ceiling systems, chimneys, fireplaces, balconies and decks; and 

checklists for builders, designers, and plan checkers—can be found 

in FEMA’s Homebuilder’s Guide to Earthquake Resistant Design and 

Construction (FEMA 2006).

Wind Zones in the United States

For More Information on 

Construction in Tornado 

and High Wind Areas

FEMA. Home Builder’s Guide to Coastal 

Construction. Federal Energy Management 

Association. www.fema.gov/library/

viewRecord.do?id=1570

FEMA. 2008. Taking Shelter from the Storm: 

Building a Safe Room for Your Home or Small 

Business, FEMA 320, Third Edition, Federal 

Emergency Management Agency,

www.fema.gov/library/viewRecord.do?id=1536

Institute for Business and Home Safety. 

2008. Fortified for Safer Living Builders 

Guide, 2008 Edition. www.ibhs.org.

NAHB. 2008. “Fire Official Surge Sweeps 

Sprinkler Mandate to Victory,” Nation’s 

Building News, September 22, 2008. 

www.nbnnews.com/NBN/issues/2008-09-22/

Zone I 

(130 mph)

Zone II 

(160 mph)

Zone III 

(200 mph)

Zone IV 

(250 mph)

Wind Zones

For More Information 

on Seismic Events

FEMA. 2006. Homebuilder’s Guide to 

Earthquake Resistant Design and Construction. 

Federal Emergency Management Agency 

www.fema.gov/library/viewRecord.do?id=2103

2009 IRC. 2009. International Residential Code - 

One and Two-Family Dwellings, Section R301.2.2. 

International Code Council, Washington, DC. 

www.iccsafe.org/Store/Pages

USGS. Earthquake Hazards Program. 

http://earthquake.usgs.gov/research/hazmaps/

(Figure Source: FEMA 2008)

CHAPTER 5 / BUILDING AMERICA BEST PRACTICES SERIES

5.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Forest Fires

Each year the United States experiences approximately 10,600 forest 

fires, burning an average of 960,000 acres. Most of these fires occur 

in the heavily forested western states. Western parts of the cold 

climate are susceptible to forest fires, particularly during the hot, dry 

summers and early fall. 

The Institute for Business and Home Safety provides several 

recommendations for building in areas of high forest fire danger:

•	 Locate the building away from ridge tops, canyons, and areas 

between high points on a ridge. 

•	 Use roofing material with Underwriters Laboratories Class A or leastcombustible fire ratings (e.g., asphalt-fiberglass shingles, steel, clay 

or concrete tiles). With tile and shingle roofs, any gaps at ends must 

be blocked to prevent embers from entering underlayment. Complex 

roof designs are more hazardous in a fire than simple roof designs. 

•	 Cover eave vents with a minimum 18-inch metal mesh screen. 

•	 Use non-combustible siding, including fiber cement, traditional “threecoat” stucco, and brick, rather than vinyl or untreated wood siding. 

•	 Install 1⁄2-inch mesh spark arrestors in fireplace chimneys. 

•	 Use non-combustible materials like metal and stone for fences that 

attach to the house. Use metal rather than vinyl gutters. 

•	 Keep plantings away from walls; plant trees far enough away so 

that trees will not overhang the roof; thin plants and trees within 

30 feet of the structure. 

•	 Use fire-retardant-treated wood or wood-plastic composite decking 

or consider stone or concrete patios rather than wood decks.

Forest Fires

Forest fire danger in the United States for a 

typical late summer day (observed August 31, 2009) 

Forest fire danger is high in the west in 

late summer, even in the marine climate, 

due to low precipitation levels July 

through September.

For More Information 

on Construction in WildfireProne Areas

FEMA. Prepare for a Wildfire. www.fema.gov/

hazard/wildfire/wf_prepare.shtm

Institute for Business and Home Safety. 2008. 

Protect Your Property from Wildfire, Pacific 

Northwest Edition, www.disastersafety.org/text.

asp?id=wildfire_main

Institute for Business and Home Safety. 

“Quick Tips for Creating a WildfireResistant Exterior” http://disastersafety.org/

projects/?id=1425&category=1136

International Code Council. 2006. 2006 ICC: 

International Wildland Urban Interface Code, 

www.iccsafe.org/Store

NFPA. Safer from the Start – A Guide to 

Firewise-Friendly Developments, National 

Fire Protection Association, http://catalog.

cmsassociates.com/firewise/index.

php?page=item&id=469&icn=18156

University of California. “Builders’ Wildfire 

Mitigation Guide,” http://firecenter.berkeley.edu/

bwmg/

(Figure source: WFAS-MAPS 

Graphics, Fire Behavior Research 

Center, Missoula, Montana, U.S. 

Forest Service)

LEGEND

Reporting 

Weather 

Stations

Low

Moderate

High

Very High

Extreme

Water

5.9

CHAPTER 5. THE COLD & VERY COLD CLIMATES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 5.9
Considering Solar Gain in Siting & Design

Passive and active solar design elements can be incorporated into 

homes throughout the cold climate, especially in the West and 

Southwest. Design considerations include lot orientation, roof tilt, 

overhangs, windows, and shading.

Lot Orientation and Home Siting 

One virtually no-cost option for improving energy performance is 

to subdivide for solar orientation (see subdivision layout figure). 

In the heating-dominated cold climate regions, builders can use 

passive solar orientation to take full advantage of the sun’s natural 

heat. By facing the long side of a home to the south and the short 

sides to the east and west, the building will capture solar heat in 

the winter and block solar gain in the summer. While the ideal 

orientation would be to face the home’s long side directly into the 

sun, it can be oriented up to 30 degrees away from due south and 

lose only 5% of the potential heating savings. Locating windows on 

the home’s south side will enhance its passive solar performance. If 

the south-facing window area reaches 8% to 10% of floor area, the 

home can be called “sun tempered.” A home with south-facing glass 

area of 15% to 20% of floor area would be called a true passive solar 

home; this much south-facing glass requires thermal storage mass and 

summer shading to mitigate summer heat gains.

A study done in the Pacific Northwest by the Bonneville Power 

Administration placed passive solar home space-heating savings 

between 10% and 20%, and a study by the City of San Jose, California, 

estimated savings for cooling costs between 10% and 40% (Iris 

Communications, Inc. 1995). The homes in both of these studies were 

oriented to the sun but did not include any special solar design features. 

East- and west-facing walls receive a large amount of solar heat from 

the low-angle sun as it rises and sets. To minimize overheating during 

spring and fall, builders should limit the amount of west-facing glass. 

Home siting for roof-mounted solar photovoltaics benefits from an 

orientation that provides significant south-facing roof area but due 

south is not necessary. In the cold climate, where the optimal tilt 

angle varies from 30° in the south to 48° in Alaska, at an azimuth 

of 0° (due south) the tilt can run from flat (0°) all the way to a roof 

pitch of 70° and still receive 90% to 100% of available energy. If the 

tilt is at the optimum of 30°, the azimuth could vary to about 65° 

either east or west in the south or 50° in the north and still receive 

90% to 100% of the available energy (Christensen and Barker 2001).

Plan subdivision lot lines and 

roads for predominantly north 

and south orientation

N

N

Subdivision with

predominantly

north- and southfacing sites for 

higher solar panel 

exposure to sun

Typical Subdivision

S

p

n

f

h

e

N

CHAPTER 5 / BUILDING AMERICA BEST PRACTICES SERIES

5.10 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
For More Information on Solar Orientation

Christensen, C.B., and G.M. Barker. 2001. “Effects of Tilt and Azimuth on Annual Incident Solar Radiation for United States Locations,” NREL 

Report No. CP-550-32966, In Solar Engineering 2001: Proceedings of the International Solar Energy Conference, S.J. Kleis and C.E. Bingham 

(eds.), Presented at FORUM 2001, April 21–25, 2001, Washington, DC, The American Society of Mechanical Engineers (ASME), New York.

DOE. 2007. Building America Best Practices Series for High-Performance Technologies: Volume 6, Solar Thermal & Photovoltaic Systems. 

U.S. Department of Energy Building America Program, www.buildingamerica.gov

Iris Communications, Inc. 1995. “Turn to Solar for Lower Heating Costs” Energy Source Builder #42, December 1995, 

www.oikos.com/esb/42/solar.html

National Renewable Energy Laboratory. Solar Maps, www.nrel.gov/gis/solar.html

University of Oregon. Sun charts available free at http://solardat.uoregon.edu/SunChartProgram.html

Viera, R.K., K.G. Sheinkopf, and J.K. Stone. 1992. Energy-Efficient Florida Home Building. 3rd printing. Florida Solar Energy Center. 

FSEC-GP-33-88. Cocoa Beach, Florida.

U.S. Solar Resource

This map shows an annual average of the kilowatt hours per day of solar energy available per square meter across the 

United States. As shown on the map, the cold climate has 5 or more kWh/m2/day of solar resource available.

(Annual average solar resource data are shown for a tilt-latitude collector. The data for Hawaii and the 48 contiguous 

states are a 10-km satellite modeled dataset [SUNY/NREL 2007] representing data from 1998-2005. The data for Alaska 

are a 40-km dataset produced by the Climatological Solar Radiation Model [NREL, 2003].)

(Map source: National Renewable Energy Laboratory, www.nrel.gov/gis/solar.html)

Author: Bill Roberts - October 20, 2008

This map was produced by 

the National Renewable 

Energy Laboratory for the U.S. 

Department of Energy.

5.11

CHAPTER 5. THE COLD & VERY COLD CLIMATES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 5.11
Overhangs

When positioning buildings to get the maximum passive solar 

benefit, overhangs can help manage heat gain and glare. Roofs 

should be designed with overhangs and porches to shade windows 

and doors. Overhangs also provide protection from rain, hail, and 

the effects of overheating and ultraviolet radiation on siding and 

windows. Overhangs may take the form of eaves, porches, awnings, 

pergolas, or trellises. Overhangs should be sized to account for 

differences in sun angles, elevation, window height and width, wall 

height above the window, and amount of shading desired based on 

time of day and time of year. 

Free and low-cost computer programs are available for sizing 

overhangs based on location. A free program telling you the 

angle of the sun for any point in the country is available at 

www.susdesign.com/sunangle/. Latitude, longitude, and elevation 

data can be obtained at www.wunderground.com/calculators/solar.

html. Optimal overhang dimensions can be calculated at 

www.susdesign.com/overhang/index.php. For example in Santa 

Fe, New Mexico, a 3-ft high by 4-ft wide window positioned 2 

feet below the overhang would need an overhang extending 1.5 

feet to provide full shade at mid-summer at 2 pm. For a list of 

free and available-for-purchase energy models, including solar 

design tools, see DOE’s Building Technologies Program website 

at http://apps1.eere.energy.gov/buildings/tools_directory/subjects.

cfm/pagename=subjects/pagename_menu=other_applications/

pagename_submenu=solar_climate_analysis. A low-cost sun 

angle calculator is available from the Society of Building Science 

Educators at www.sbse.org/resources/sac/index.htm.

Windows

Windows should be selected to manage the quantity of heat loss 

and solar gain. In the heating-dominated cold climate, it is 

preferable to use windows with a lower U-value and a higher solar 

heat gain coefficient (SHGC). The U-value is a measure of heat 

transfer. The lower the U-value the better the window performs 

at stopping heat flow. The SHGC measures how well the window 

blocks heat caused by sunlight. The lower the rating the less solar 

heat the window transmits. The IECC requires a window U-value 

of 0.35 or lower in the cold climate; no SHGC is specified. For 

more information about windows, see Chapter 8 of this guide 

and also see the Efficient Windows Collaborative website at 

www.efficientwindows.org.

Winter

Sun

Summer

Sun

32o

4 ft.

71o

Sun angles vary by latitude

Winter

Sun

Summer

Sun

26o

4 ft.

68o

Winter

Sun

Summer

Sun

21o

4 ft.

64o

Santa Fe, 

New Mexico

Albany, 

New York

Spokane, 

Washington

Sun angles vary by latitude, season, 

and time of day. Sun angles shown here 

are calculated for noon on June 21 and 

December 21. (Source: Sustainable by 

Design, www.susdesugn.com/sunangle)

CHAPTER 5 / BUILDING AMERICA BEST PRACTICES SERIES

5.12 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Shading 

Shade can be provided by intentional planting or preservation of 

existing trees on the site. Tree preservation increases salability. Native 

trees are the most beneficial to the environment. The NAHB reports 

in its survey of buyers, What 21st Century Home Buyers Want, that 

over 80% of respondents in the West rated trees as essential or 

desirable (NAHB 2002). American Forests and the NAHB (1995) 

found that mature trees may add from $3,000 to $15,000 to the 

value of a residential lot.

Truly cool neighborhoods have trees. A study in Florida has 

shown that a subdivision with mature trees had cooler outside air 

with less wind velocity than a nearby development without trees 

(Sonne and Viera 2000). The development with a tree canopy had 

peak afternoon temperatures during July that were 1.1°F to 3.1°F 

(± 0.7°F) cooler than the site without trees. The total effect of 

shading—lower summer air temperature and reduced wind speed—

can reduce cooling costs by 5% to 10% (McPherson et al. 1994). 

While evergreen trees may provide better wind protection, deciduous 

trees are ideal for summer shading in the cold climate because their 

lack of leaves in the winter will not block desirable solar gain during 

the heating season. Trees reduce cooling requirements, particularly 

when located on the south and west side of the home to block 

low-angle, late-afternoon, peak solar-gain sun. Trees more than 

35 feet from the structure are too far away for shade.

The Colorado State University Extension reported that proper use 

of deciduous shade trees could cut cooling bills more than 20%. 

They also noted that research into windbreaks conducted on the 

Great Plains showed winter heating energy savings of up to 25% 

were possible when evergreen trees and shrubs were properly placed 

on the north and east sides of homes (Walker and Newman 2009). 

One or more rows of evergreens placed along the corner of the home 

that faces prevailing winds provides an effective windbreak. The 

optimal distance of the windbreak from the home for reducing wind 

velocity is one to three times tree height. A thick hedge of evergreen 

shrubs planted 4 to 8 feet from the foundation along the northwest 

corner of the home can create a trapped dead air space that helps to 

insulate the home.

Care should be taken not to shade roof-mounted solar equipment 

(e.g., photovoltaic panels and solar thermal water heating panels) 

or areas of the roof that could be reserved for future solar 

installations. A simple rule of thumb is that any potential shading 

Careful landscaping can 

preserve roof-top solar 

exposure and provide shading 

to help control solar gain 

through windows.

Large deciduous shade trees on the southwest corner of the home provide welcome 

relief from summer afternoon sun while 

allowing desirable winter sun to warm the 

house. (Source: Colorado State University 

Extension, Walker and Newman 2009).

A thick hedge of evergreen trees planted 

on the corner facing prevailing winds 

provides a windbreak. (Source: Colorado 

State University Extension, Walker and 

Newman 2009).

EVERGREEN

SHRUBS 

EVERGREEN

TREES 

EVERGREEN

SHRUBS 

DEAD AIR 

SPACE 

SUN POCKET

HOUSE

EVERGREEN WINDBREAK

N

DECIDUOUS

SHADE TREES 

5.13

CHAPTER 5. THE COLD & VERY COLD CLIMATES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 5.13
structure should be twice as far away from the solar equipment as 

the structure is tall. Sun charts and digital tools are available to 

assess how obstructions such as trees, buildings, or chimneys will fall 

between the solar panel and the sun at various times of the year.

Established trees can also provide a ground-stabilizing force in areas 

with sloped lots that may be at higher risk of erosion and mud slides.

For More Information on Shade

American Forests and the National Association of Homebuilders. 1995. Building Greener 

Neighborhoods: Trees as Part of the Plan. NAHB, Washington, D.C. 

www.nahb.org/product_details.aspx?forsaleID=26

McPherson, G.E., D.J. Nowak, and R.A. Rowntree (eds). 1994. Chicago’s Urban Forest 

Ecosystem: Results of the Chicago Urban Forest Climate Project. U.S. Department of 

Agriculture, Forest Service, Northeastern Research Station, 

www.treesearch.fs.fed.us/pubs/4285

National Association of Home Builders. 2002. What 21st Century Homebuyers Want: 

A Survey of Customer Preferences, National Association of Home Builders, 

www.BuilderBooks.com

Walker, L. and S. Newman. 2009. Landscaping for Energy Conservation. No 7.225, 

Colorado State University Extension. www.ext.colostate.edu/pubs/garden/07225.html

Moss

In climates with high humidity, unwanted moss and algae can 

grow on roofs—especially on north- and east-facing surfaces 

where they can stain and damage most roofing types. To inhibit 

moss and algae growth, roofs must have sunlight and airflow, 

allowing them to dry properly. Options for inhibiting moss growth 

in heavily treed areas include using metal roofs, installing metallic 

zinc or copper strips along the roof just beneath the peak, or 

using copper-treated asphalt shingles. The better option from an 

environmental (and cost) standpoint is to allow adequate air and 

light to reach the roof by planting and trimming trees so that 

branches do not overhang the roof. 

For More Information on Moss 

City of Portland. “Safe Roof Moss Control,” Portland Bureau of Environmental Services, 

City of Portland, Oregon, www.portlandonline.com/BES/index.cfm?c=50367

For houses with solar photovoltaic roof 

panels, any potential shading structure 

should be twice as far away from the 

photovoltaic array as it is tall (D = 2 * H)

D D

H

H

New roofs are not immune to moss, which 

can spread quickly under favorable conditions 

like constant shade and low roof pitch.

CHAPTER 5 / BUILDING AMERICA BEST PRACTICES SERIES

5.14 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
This chapter introduces fundamental principles of building science, 

including the systems approach to house design. The dynamic 

forces that drive the movement of moisture, air flow, and heat 

in homes are described. This background information helps to 

explain the underpinnings of the best practices described in later 

chapters. In applying building science, the goal is to design and 

build houses that work within the bounds of natural forces, and in 

some cases to put these forces to work for occupant comfort and 

building efficiency.

The Systems Approach 

Building America takes a systems approach to home design 

recognizing that, as buildings become increasingly efficient, one must 

take into account the interactions of all of the home’s components 

and subassemblies, both to maximize performance and to avoid 

catastrophe. This “whole-house” approach recognizes that changes 

in one or a few components can dramatically change how other 

components perform, affecting overall building energy use, comfort, 

and durability.

Building Science Basics

The successful builder needs to understand all of the forces that 

affect a house and how these forces interact with each other and the 

home’s components. These forces include water, vapor, air flow, heat 

transfer, and occupants.

Chapter 6.

Building Science and 

the Systems Approach

When builders design houses to work 

well as a system, not only do the houses 

save energy, they also are better able to 

withstand the elements. (Photo source: Leif 

Juell, Alternative Power Enterprises, Inc.)

“Most builders view each aspect 

of the house—the electrical work, 

the plumbing, the framework—as 

separate jobs, but the Building 

America approach views each 

area as part of the whole...If you 

view the whole house as the 

system...it’s not only easier, you 

end up with a better product.” 

Lee Rayburn, developer of 

Centennial Terrace in Tucson, Arizona

CHAPTER TOPICS

6.1 The Systems Approach

6.1 Building Science Basics

6.3 Water

6.3 Vapor

6.5 Air Flow

6.6 Heat Transfer

6.9 Occupants

6.1

CHAPTER 6. BUILDING SCIENCE AND THE SYSTEMS APPROACH

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 6.1
The Systems Approach 

to House Design

In a system-designed house all the 

parts are designed to work together for 

a healthy, durable home that minimizes 

builder callbacks while cutting energy, 

maintenance, and repair costs down 

the road.

A. Air Sealing: Helps maintain proper 

pressure balance in the home and 

stops stack effect, limiting drafts 

and keeping humidity, soil gases, 

and garage contaminants out of the 

house. It also creates a barrier to 

rodents and insects.

B. Well-Designed Moisture Barriers 

and Drainage: Avoids expensive 

structural damage and helps stop 

humidity, mold, and mildew.

C. Insulation: Holds comfortable 

temperatures in conditioned 

spaces and helps control noise. For 

insulation level recommendations, 

visit www.ornl.gov/sci/roofs+walls/

insulation/ins_16.html

D. Right-Sized and High-Efficiency 

HVAC Equipment: Costs less to 

install than bigger equipment, 

saves energy, and is designed to 

comfortably handle heating and 

cooling loads.

E. Ventilation: Exhaust fans 

remove moisture and pollutants. 

A controlled, filtered air intake 

ensures plenty of fresh air.

F. Sealed Combustion Appliances:

Reduce moisture buildup and 

ensure the safe removal of 

combustion gases with sealed 

combustion appliances. 

G. Compact and Tightly Sealed 

Duct Runs: Short, straight duct 

runs in conditioned space yield 

better airflow with less chance 

for leaks and fewer contaminants 

like humidity and dust from 

attics or crawlspaces. Leaky 

ducts are a major contributor to 

mold problems. Multiple return 

air paths ensure balanced air 

pressure for less drafts and 

more balanced temperatures 

throughout the house. Ducts 

are in conditioned space.

H. Efficient Windows: Help to 

reduce heating and cooling 

loads. Window flashing protects 

against water leaks.

I. Overhangs: Provide shade, 

reduce cooling load, and direct 

water away from the house.

E

G

F

I

D

H

B

C

A

A

CHAPTER 6 / BUILDING AMERICA BEST PRACTICES SERIES

6.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Water

Rainwater wants to flow down and will take the path of least resistance. 

To minimize mold and moisture damage in homes, builders must 

become experts in moisture-management techniques, learning how 

to guide rainwater off or out of the structure and how to incorporate 

redundant levels of moisture protection into the home’s building shell. 

Liquid moisture can also originate in the ground and flow upwards. 

This uptake is due to capillary action that is related to the adhesive 

properties of water. Water is attracted to other water. This is called 

cohesion. Water is also attracted to other materials. This is called 

adhesion. Capillary action allows water to climb up into seemingly 

solid materials through pores in the material. A capillary break is a 

non-permeable material that blocks the capillary flow of water from 

the ground. See Chapter 8 for more details.

Vapor

Water in its liquid state is not the only problem; water vapor can 

also be a source of damage. Water vapor causes problems when it is 

trapped within a building assembly, such as a wall cavity. When warm 

air touches a cold surface, the water vapor it carries can condense, 

turning into its liquid form, where it can cause damage to structural 

components. Condensation can also form in and on ductwork, 

especially when air conditioning cools duct surfaces that come in 

contact with humid air, such as in a vented attic or crawlspace.

Unlike moisture in its liquid form, water vapor travels wherever air 

flows. Air is vapor’s heavy lifter. Where there are air leaks, there are 

vapor leaks. Stopping air leaks by thoroughly air sealing the building 

envelope is an important step in limiting damage from water vapor.

Water vapor also can be carried by diffusion, which can force vapor 

through materials and into places it shouldn’t be, such as wall 

cavities. Differences in vapor pressure and temperature are the forces 

that drive diffusion. Vapor diffusion moves moisture from areas of 

higher vapor pressure to areas of lower vapor pressure, and from 

areas of higher temperature to areas of lower temperature.

Vapor movement through a building component can be impeded by 

use of a vapor diffusion retarder. Vapor retarders are sometimes called 

vapor barriers but vapor barrier is a misnomer because all materials 

will allow some transmission of vapor, even if only a small amount. 

The ability of a material to retard the diffusion of water vapor is 

measured by units known as “perms” referring to the material’s 

permeability. A perm is a measure of the amount of water vapor that 

passes through a material over a fixed period of time; the higher the 

number, the more easily water vapor can pass through. Code defines 

(top) When moisture is trapped inside 

walls, mold can grow unchecked, causing 

damage to the walls and health impacts for 

the occupants. (Photo source: EPA; photo 

by Terry Brennan)

(middle and bottom) This sprinkler was 

placed too close to the house’s foundation 

wall. Moisture seeped through the concrete 

block causing water stains and mold inside. 

(Photo source: EPA; photo by Terry Brennan)

6.3

CHAPTER 6. BUILDING SCIENCE AND THE SYSTEMS APPROACH

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 6.3
classes of vapor retarders based on their perm ratings (see table 

below). Vapor retarder requirements were removed in the 2009 IECC; 

however, vapor retarder requirements are addressed in the 2009 IRC. 

How, where, and whether a 

vapor diffusion retarder should 

be used depends on the climate. 

Typically, the number of 

Heating Degree Days (HDD) in 

an area is used to help make these determinations. (See Chapter 5 for 

a comparison of Building America climate zones and IECC climate 

zones.) In the cold and very cold climates (equivalent to IECC climate 

zones 5, 6, and 7), the vapor retarder should be located on the warm 

side of the wall, i.e., on the interior side of the insulation.

2009 IRC R601.3 specifies 

the use of Class I or II vapor 

retarders on the interior side 

of framed walls in IECC 

climate zones 4c, 5, 6, 7, and 

8; however, per a change in the 

2009 IRC from the 2006 IRC, 

Class III vapor retarders are now 

permitted in all of these climate 

zones under certain conditions. 

The 2009 IRC R601.3.1 allows 

the use of Class III vapor 

retarders (such as latex paint) 

instead of Class 1 or Class II 

vapor retarders when the wall 

assembly allows drying through 

the use of ventilated claddings or 

reduces closed-cavity condensation potential through the use of exterior 

insulating sheathings. See the table on Class III vapor retarders for a 

listing of specific requirements in each IECC climate zone under which 

Class III vapor retarders are permitted in IECC zones 5, 6, 7, and 8. 

The 2009 IRC 601.3 also specifies that Class I or Class II vapor 

retarders are not required in IECC zones 5, 6, 7, and 8 under the 

following conditions: basement walls, in the below-grade portion of 

any wall, or in construction where moisture or frozen moisture will 

not damage the materials used in the assembly. (See the sidebar on 

the following page for a discussion of this exception). 

While Class 1 vapor retarders are not required in any climate zone, 

their use is most applicable in the very cold and subarctic climates. 

(See sidebar and see Building Science Corporation 2008 and Lstiburek 

2006 for more information and wall construction examples).

A Heating Degree Day 

is a unit that measures how often outdoor 

daily dry-bulb temperatures fall below an 

assumed base, normally 65°F (18°C)

Class III Vapor Retarders 

Permitted in Cold Climate 

under Following Conditions 

(source: 2009 IRC Table R601.3.1)

Zone Class III vapor retarders 

permitted for:

5 •	Vented cladding over OSB

•	Vented cladding over plywood

•	Vented cladding over fiberboard

•	Vented cladding over gypsum

•	Insulated sheathing with R-value

≥ R-5 over 2x4 wall 

•	Insulated sheathing with R-value

≥ R-7.5 over 2x6 wall

6 •	Vented cladding over fiberboard

•	Vented cladding over gypsum

•	Insulated sheathing with R-value

≥ R-7.5 over 2x4 wall 

•	Insulated sheathing with R-value

≥ R-11.25 over 2x6 wall

7 & 8 •	Insulated sheathing with R-value

≥ R-10 over 2x4 wall 

•	Insulated sheathing with R-value

≥ R-15 over 2x6 wall

Perm Ratings of Common 

Sheathing Materials

Plywood sheathing More than 

1.0 perm 

OSB More than 

1.0 perm 

Exterior gypsum More than 

1.0 perm 

Fiberboard sheathing More than 

1.0 perm 

Extruded polystyrene 

foam sheathing 1 inch

1.0 perm 

or less

Film-faced extruded 

polystyrene 0.5 inch thick 

with perforated facing 

More than 

1.0 perm 

Nonperforeated foil-faced 

rigid insulation

Less than 

0.1 perm

Polypropylene-faced 

rigid insulation

Less than 

0.1 perm

Three-coat, hard-coat 

stucco over 2 layers of 

Type D asphalt-saturated 

Kraft paper and OSB

Less than 

1.0 perm

Source: Lstiburek 2006. See Building Science 

Corporation 2006 for an extensive list of 

building material perm ratings.

Vapor Retarder Definitions

The 2009 IRC R601.3 gives the following 

definitions and examples for vapor 

retarder classes:

Class Definition Examples

I 0.1 perm 

or less

Sheet polyethylene, sheet metal, 

non-perforated 

aluminum foil

II Greater than 

0.1 perm to 

less than 

1.0 perm

Kraft-faced 

fiberglass batts 

or low-perm 

paint

III Greater than 

1.0 perm to 

less than 

10 perm

Latex or enamel 

paint

CHAPTER 6 / BUILDING AMERICA BEST PRACTICES SERIES

6.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Air Flow

Air enters a home through openings in walls, cracks around doors 

and windows, and at intersections of building assemblies. Key 

points of air entry include rim joists where foundations meet floors 

and walls, where walls and floors for upper stories join together, 

and where walls intersect the roof. The pressure difference between 

indoor and outdoor air (or between indoor air and soil gas), 

temperature differences, and wind are the driving forces of air 

infiltration. Plugging air leaks is one way to slow down infiltration.

Air movement can affect how well insulation works. When outside 

air is pushed through insulation in places such as attics, walls, or 

crawlspaces, it robs the insulation’s ability to slow down heat loss. 

This process is called wind wash or air intrusion. Using baffles, 

dams, and wind blocks in attics keeps ventilation ports open and 

directs air away from the insulation.

Controlled air movement in the right place is beneficial. Providing a 

ventilation space behind exterior wall cladding allows the material to 

dry out and prevents the moisture from contaminating housewraps, 

sheathing, or other wall components. Wall venting behind brick 

veneers is especially important. Under the right conditions, energy 

from the sun can push vapor through wet brick with the force of a 

steam boiler. Ventilation cavities behind brick help to dissipate this 

vapor before it is injected into the framed cavity. 

Crawlspaces and attics are other areas in homes that have traditionally 

used passive ventilation to dissipate moisture.

Researchers and builders have developed methods of building unvented, 

conditioned attics and crawlspaces, and sealing these areas may be 

recommended if they are to provide conditioned space to house HVAC 

equipment and ducts. (See Chapter 8 for more on crawlspaces.)

Planned ventilation is needed to provide a healthy and comfortable 

indoor environment. Relying on air leakage to provide ventilation 

and combustion air is unreliable. By its nature, infiltration is not a 

reliable form of ventilation. It depends on pressure and temperature 

differentials that change constantly. Air leaks may also carry 

with them moisture that can cause structural or mold problems. 

Combustion in furnaces, fireplaces, dryers, and cooking appliances 

requires air. If multiple combustion or exhaust systems are drawing 

air at the same time and if these appliances are not all direct vented 

to the outdoors, there is a chance that combustion appliances can 

backdraft, drawing flue gases into a home rather than expelling them 

outdoors. Mechanical ventilation and sealed combustion systems are 

described in Chapter 9.

Use of Class I or Class II Vapor 

Retarders in Basements in 

Cold Climates 

The 2009 IRC 601.3 specifies Class I or 

Class II vapor retarder in zones 4c, 5, 6, 7, or 

8 “except on the following: basement walls, 

in the below-grade portion of any wall, or 

in construction where moisture or frozen 

moisture will not damage the materials used 

in the assembly.” This exception is explained in 

Building Science Corporation 2008 as follows: 

“Below grade spaces such as basements are 

of particular concern with respect to Class I 

vapor control layers. Because the moisture 

drive in below grade walls is always to the 

interior, installing a high level of vapor control 

on the interior of the wall will cause moisture 

related durability issues by trapping moisture 

in the enclosure (see BSD-103: Understanding 

Basements). However, a Class I vapor 

control layer could be used in a below grade 

assembly under the following conditions: 

(a) no moisture-sensitive material is trapped 

between the concrete and the Class I vapor 

control layer, (b) this space is completely 

isolated from air communication with the 

interior, and (c) the Class I vapor control 

layer is protected from interior-sourced 

condensation. An example of this assembly 

would be foil-faced polyisocyanurate applied 

to the basement wall, with a gap between the 

insulation and the concrete isolated and air 

sealed from the interior.”

Nelson Construction of Farmington, 

Connecticut, uses two inches of foil-faced 

polyisocyanurate insulating sheathing 

taped at the seams for an insulated air 

sealed exterior that is finished with Tyvek 

house wrap and vinyl siding.

Water-Carrying Capacity of 

Diffusion vs. Air Flow

Research shows 30 times more water 

vapor is carried through walls by air flow 

than by diffusion.

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Heat Transfer

Heat travels via three mechanisms: conduction, convection, 

and radiation. 

Conduction

Conduction is the movement of heat through a material. It is the 

cause of a hot handle on a sauce pan simmering away on a range 

top. Heat flows from warm areas to cold areas. The larger the 

temperature difference between the areas the faster heat will flow. 

The ability of materials to resist heat flow influences conduction. 

Insulation is very good at resisting conducted heat flow. Dimensional 

lumber is not very good at resisting heat flow. The best way to 

slow down conduction is to add insulation to building envelope 

assemblies. It is important that insulation be installed to fill all voids 

in the building envelope. It is easier to fill voids using blown-in or 

sprayfoam insulation than with batt insulation. Blown cellulose or 

fiberglass insulation for example flows almost like a liquid, filling 

Unintentional air leaks can allow leakage 

of significant amounts of air into and out 

of a home in an uncontrolled manner 

through unsealed seams and unplugged 

holes in the walls, ceiling, and floors. 

(Figure source: EPA)

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6.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
in areas behind wiring and framing where batt insulation might be 

compressed or blocked. Spray foam is applied as a liquid and also 

fills voids that may be difficult to reach with batts. Batts work well 

in large, uninterrupted areas if installed properly. 

The rate at which heat flows through a material is described using 

two terms: R-value and U-value. Resistance to heat flow is called 

R-value, the higher the R-value the more resistant a material is to 

heat conduction. R-values can be added together to calculate how 

well an entire assembly will resist heat flow. 

Conductivity is described using U-value. Conductivity refers to 

how well a material or assembly conducts heat. It is inversely 

proportional to R-value. If the U-value is high, then the R-value 

is low. From an energy-efficiency perspective, high R-values and 

low U-values are good. U-values may be calculated for an entire 

assembly or for an individual component. However, U-values for a 

number of components cannot be added together to calculate the 

overall U-value for an assembly such as a wall.

Convection

Convection is the movement of heat via a gas or liquid. Warm air 

becomes buoyant, while cold air tends to sink. Convection is the 

force that draws hot air up a chimney. This force is sometimes called 

the stack effect. 

Designers and builders can use convection as a natural way to cool 

and ventilate a home, but it can cause problems in the wrong places 

and circumstances.

In cooler climates, heated air tends to rise to the top of tall structures. 

Warmer air becomes buoyant and can carry more moisture than 

cool air. Near cold surfaces, such as inefficient windows, cooler air 

drops. As the air cools below the dew point, it must give up some of 

its moisture, which then condenses on the cold surface. This is why 

windows sometimes have condensation in wintertime.

In the summer, air-conditioned structures, colder air sinks, drawing 

in warmer air through leaks in the building envelope. Warmer air 

carries more moisture than cold air; as it cools, this moisture may 

condense inside structural assemblies. This outside air can also 

increase indoor humidity levels, causing occupants to turn up the air 

conditioner, which exacerbates the problem. 

Convective air currents can set up wherever differences in air pressure 

drive air movement. This applies to the house as a whole, and to 

smaller spaces. Convective loops can occur in cavities inside walls 

Conduction

Heat transferred by contact, like the hot 

pan that fries an egg or the hot asphalt 

that burns bare feet.

Convection

Heat transferred via air 

or liquid movement in 

a pattern of cooling/

falling and warming/

rising like hot water 

that rises and falls 

in a percolating 

coffee pot.

Radiation

Heat transferred through 

space by rays, like rays 

of sun that warm your 

skin if the rays 

are not blocked by 

a building or tree.

Stack Effect

The stack effect is the flow of air that 

results from warm air rising, creating a 

positive pressure area at the top of a 

building and a negative pressure area at 

the bottom of a building. The stack effect 

can overpower the mechanical system 

and disrupt ventilation and circulation 

in a building. It pulls unfiltered air and 

soil gases into a home through cracks 

in the foundation and around doors and 

windows and it draws conditioned air up 

and out through air leaks around ceilings, 

chimneys, flue, and pipe chases.

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Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 6.7
where there are voids in insulation, in attics, and even between tightfitting blinds and inefficient windows. Differences in temperature 

between the conditioned space and outdoors can create enough of a 

pressure difference inside a wall cavity to form a convective loop.

The most effective strategies for stemming convective heat losses are 

to avoid air temperature differentials inside structures, to fully fill 

insulated cavities with insulation (no voids), and to seal air leaks. 

Properly installing adequate insulation eliminates cold spots in walls 

and structural cavities. Sealing air leaks blocks air movement and 

minimizes the temperature differentials that occur when conditioned 

and unconditioned air mix.

Radiation

Radiation is the movement of heat by solar or infrared rays. 

For example, much of the heat from a woodstove is in the form 

of radiation. The key to radiation is that, unlike conduction or 

convection, this process does not involve a molecular connection 

between the source and the recipient of the heat. That is one reason 

a person sitting across the room feels toasty from a radiant heater, 

such as a woodstove. Heat can be transferred through a vacuum 

via radiation; this is how heat from the sun is transferred to Earth 

through the vacuum of space. 

Radiant heat can influence comfort. In a house with a reasonable 

indoor temperature, radiant heat from a hot window or wall can 

influence the comfort level of building occupants. In cold climates, 

heat radiating from occupants to a cold window or wall can make 

them feel colder. On the other hand, when indoor warming is 

needed, an occupant exposed to radiant floor heating may feel 

warmer than the air temperature suggests. 

Techniques for controlling solar radiation heat gain include tree 

shading and window awnings or overhangs. Radiant barriers installed 

in the attic and light-colored roofing material are used to minimize 

solar heat gain in the hot dry and hot humid climates but are not 

recommended in the heating-dominated areas of the cold climate. 

At night, a house can radiate heat to a clear night sky. The resulting 

cooling can lead to condensation in attics and roof wetting. 

Researchers are exploring ways to use radiation to the night sky 

as a passive way to cool homes.

Occupants

Occupants are a force unto themselves, not tied directly to climate or 

building dynamics but able to strongly influence building performance. 

Living Room

Loft

Crawlspace

Screened 

Porch

Window

Building America’s research team lead 

Building Science Corporation used 

convection to help cool this structural 

insulated panel (SIP) cottage in Georgia. 

Cool air from the screened porches is 

drawn into the building’s interior where 

it heats up and is pulled up and out the 

second-story windows, drawing more air 

in through the shaded first-story windows.

Screened 

Porch

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6.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Occupant comfort and costs are at the center of design considerations. 

However, as the building operators and maintainers, occupants can do 

much to correct or unbalance a system. Providing correct information 

in the form of owners manuals, homeowner education, and accurate 

marketing materials can help occupants make decisions that will 

contribute to their home’s longevity, comfort, and efficiency.

Occupants can have an enormous impact on the energy performance 

of their homes by the selections they make in appliances, 

entertainment systems, computers, tools, and other electric 

equipment. These plug loads make up about 40% of energy loads 

in homes. As builders and researchers figure out how to make 

thermal, lighting, and ventilation equipment more efficient, these 

miscellaneous plug loads will become more and more important in 

how energy is managed in homes.

More Information on Water, Vapor, Air Flow, and 

Heat Transfer

2009 IECC. 2009. International Energy Conservation Code, International Code Council (ICC), 

Washington, DC. www.iccsafe.org/Store/Pages

2009 IRC. 2009. International Residential Code - One and Two-Family Dwellings, Section 

408.3, “Unvented Crawl Spaces,” International Code Council (ICC), Washington, D.C. 

www.iccsafe.org/Store/Pages

ASTM E-2112-07. “Standard Practice for Installation of Exterior Windows, Doors and Skylights.” 

American Society for Testing and Materials (ASTM), www.astm.org/Standards/E2112.htm

ASTM E 2266. “Standard Guide for Design and Construction of Low-Rise Frame Building 

Wall Systems to Resist Water Intrusion.” American Society for Testing and Materials (ASTM), 

www.astm.org/Standards/E2266.htm 

Buildernews Magazine. May 2004. “Housewrap Felt or Paper: Comparing specs on weather 

barriers,” www.buildernewsmag.com/index.php?option=com_content&view=article&id=1168

%3AHousewrap+Felt+or+Paper%3A&Itemid=107

Building Science Corporation. Homeowner Information Resources. 

www.buildingscience.com/resources/more-topics/homeowner_resources

Building Science Corporation. 2006. Info-500: Building Materials Property Table, Building 

Science Corporation , Created: 2010/04/16, Info-500: Building Materials Property Table

Building Science Corporation. 2008. Info-310: Vapor Control Layer Recommendations, 

By Building Science Corporation, Sept. 8, 2009, www.buildingscience.com/documents/

information-sheets/3-water-management-and-vapor-control/info-sheet-310-vapor-controllayer-recommendations?topic=resources/more-topics/vapor_barrier_code_changes

Fenestration Manufacturers Association (FMA)/American Architectural Manufacturers 

Association (AAMA) 100-07. “Standard Practice for the Installation of Windows with 

Flanges or Mounting Fins in Wood Frame Construction.” Available from AAMA’s online 

store at www.aamanetstore.org/pubstore/ProductResults.asp?cat=0&src=100

HGTVpro.com. “Improved Stucco Systems.” Article available at www.hgtvpro.com/hpro/

bp_exterior_finishes/article/0,2617,HPRO_20149_4243887,00.html

IBACOS. 2002. “Moisture Issues in Homes with Brick Veneer.” IBACOS article available at 

www.eere.energy.gov/buildings/building_america/pdfs/db/36397.pdf

Lstiburek, Joseph W. 2001. “Brick, Stucco, Housewrap and Building Papers,” RR-0105, 

Building Science.com, www.buildingscience.com/documents/reports/rr-0105-brick-stuccohousewrap-and-building-paper/

Occupant choices in appliances and home 

electronics have a big impact on plug load.

6.9

CHAPTER 6. BUILDING SCIENCE AND THE SYSTEMS APPROACH

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 6.9
Lstiburek, Joseph W. 2003. EEBA Water Management Guide. Energy and Environmental 

Building Association. Minneapolis, Minnesota. www.eeba.org/bookstore/prod-Water_

Management_Guide-9.aspx 

Lstiburek, Joseph W. 2004. “Understanding Vapor Barriers,” ASHRAE Journal, 

August 2004. www.renewable-resource.net/resources/Understanding_Vapor_Barriers

Lstiburek, Joseph W. 2006. Building Science Digest 106: Understanding Vapor Barriers. 

Building Science Press. Waterford, Massachusetts. www.buildingscience.com/documents/

digests/bsd-106-understanding-vapor-barriers

Lstiburek, Joseph W. 2008. “Concrete Floor Problems,” BSI-003, Building Science Corporation, 

www.buildingscience.com/documents/insights/bsi-003-concrete-floor-problems. 

Parker, D., J. Sherwin, J. Sonne, N. Moyer. 2002. Comparative Evaluation of the Impact of 

Roofing Systems on Residential Cooling Energy Demand in Florida. Florida Solar Energy Center, 

FSEC-CR-1220-00, http://securedb.fsec.ucf.edu/pub/pub_show_detail?v_pub_id=4120

Straube, John. 2001. “Wrapping it Up,” Canadian Architect, May 2001. 

www.cdnarchitect.com/issues/ISarticle.asp?aid=1000115982

U.S. Department of Energy. 2000. “Technology Fact Sheet on Weather-Resistive Barriers.” 

Available on the Web at www.toolbase.org/PDF/DesignGuides/weatherresistantbarriers.pdf

U.S. Department of Energy. 2009. “Residential Requirements of the 2009 International 

Energy Conservation Code,” DOE Building Energy Codes Program, PNNL-SA-65859, 

www.energycodes.gov/training/pdfs/2009_iecc_residential.pdf

U.S. Environmental Protection Agency. Mold Course - Introduction to Mold and Mold 

Remediation for Environmental and Public Health Professionals. Accessed 6/18/2009, 

www.epa.gov/mold/index.html

CHAPTER 6 / BUILDING AMERICA BEST PRACTICES SERIES

6.10 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
The building envelope is the boundary that separates interior 

comfort from exterior conditions. The envelope encompasses three 

boundaries: the thermal boundary, the pressure boundary, and the 

weather barrier.

•	 The thermal boundary consists of the building assemblies 

surrounding the space that is purposefully cooled or heated. The 

insulation plus the air barrier form the thermal boundary. 

•	 The pressure boundary is the point at which inside air and outside 

air are separated. The line where the pressure difference across 

the building shell is greatest between the inside and outside of the 

house is the pressure boundary. This boundary is where air sealing 

should occur. Thermal and pressure boundaries should be aligned. 

•	 The weather barrier includes screens to shed rain.

This chapter describes three strategies that apply to the overall building 

envelope: advanced framing, insulating, and air sealing. These strategies 

involve the entire house envelope and directly address the thermal and 

pressure boundaries. Specific practices that apply to particular assemblies, 

such as foundations, walls, and roofs, are described in the next chapter.

Advanced Framing

Optimal value engineering or advanced framing refers to framing 

techniques that require less lumber than standard framing practices 

but provide all the needed structural strength. Using less lumber 

leaves more room for insulation while saving resources and reducing 

waste. The recommendations below apply to standard framing using 

dimensional lumber. Other energy-efficient framing materials not 

described here include structural insulated panels, insulated concrete 

forms, and steel framing. 

Chapter 7.

The Overall 

Building Envelope

“Advanced framing is such a 

simple thing but very few builders 

are doing it. It is a selling point 

with customers. The performance 

characteristics are easy to point 

out to the customer and it’s 

easy to carry the energy-saving 

concepts through to other items 

like high-performance windows, 

more insulation, and air sealing.” 

Builder Barrett Burr, Olympia, Washington

CHAPTER TOPICS

7.1 Advanced Framing

7.4 Insulation

7.8 Air Sealing

7.11 The Thermal Bypass Checklist

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CHAPTER 7. THE OVERALL BUILDING ENVELOPE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 7.1
In a Building America study (described in the Partnership for 

Advancing Technology in Housing [PATH] Toolbase) advanced 

framing resulted in 50% reductions in installation and materials costs 

along with a 7% increase in the amount of wall cavity area that could 

be insulated. The simple measures taken in this project included 

single top plates, 24-inch on-center 2x6 wall studs, and standardization 

of window and door openings to match the 24-inch layout. A 

production builder in California who switched to advanced framing 

methods realized a 40% reduction in wall framing costs, for a 

materials-purchasing savings of over $1,100 per house.

A sample of advanced framing techniques includes the following:

•	 TWO-FOOT MODULE DESIGN. Starting with the foundation, 

the house exterior dimension footprint should be based on 

2-foot increments. Because sheet goods come in 4-foot by 8-foot 

dimensions, this reduces waste and cuts material costs. 

•	 FRAME 24-INCH ON-CENTER. Typical practice is to frame walls, 

floors, and often roofs at 16 inches on center. However, 24-inch 

on-center walls are structurally adequate for most residential 

applications. Even though the stud size is increased from 2x4 to 

2x6 on load-bearing walls, changing stud-spacing from 16 to 24 

inches can reduce framing lumber needs significantly. Confirm 

with local building officials because some jurisdictions in highwind areas may not allow 24-inch on-center (PATH).

•	 ALIGN FRAMING MEMBERS AND USE A SINGLE TOP PLATE.

Double top plates are used to distribute loads from framing 

members that are not aligned above studs and joists. By aligning 

framing members vertically throughout the structure, the second 

plate can be eliminated. Plate sections are cleated together using flat 

plate connectors [2009 IRC R602.3.2].

(left) Sheet goods come in 4x8-foot 

dimensions. Designing and building on a 

2-foot grid saves cutting time and reduces 

lumber and sheet good waste. 

(right) Framing details include ladder 

blocking and two-stud corners. 

(Photo source: Tommy Williams Homes)

Advanced framing techniques include 

aligning wall studs with trusses and 

using single top plates.

ladder blocking 2-stud corners

CHAPTER 7 / BUILDING AMERICA BEST PRACTICES SERIES

7.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
•	 SIZE HEADERS FOR ACTUAL LOADING CONDITIONS.

Headers are often oversized for the structural work that they 

do. Doubled-up 2x6 headers end up in non-load-bearing walls. 

Doubled-up 2x12 headers end up in load-bearing walls, regardless 

of specific loading conditions. Nonbearing walls do not need 

structural headers [2009 IRC R602.7.2]. Proper sizing may allow 

for the use of insulated headers in which foam insulation is 

sandwiched between lumber.

•	 LADDER-BLOCK EXTERIOR WALL INTERSECTIONS.

Where interior partitions intersect exterior walls, three-stud “partition 

post” or stud-block-stud configurations are typically inserted. Except 

where expressly engineered, these are unnecessary. Partitions can be 

nailed either directly to a single exterior wall stud or to flat blocks 

inserted between studs. This technique, called “ladder blocking” or 

“ladder framing,” creates room for more insulation. 

•	 USE TWO-STUD CORNERS. Exterior wall corners are typically 

framed with three studs. The third stud generally only provides 

a nailing edge for interior gypsum board and can be eliminated. 

Drywall clips, a 1x nailing strip, or a recycled plastic nailing 

strip can be used instead. Using drywall clips also reduces 

opportunities for drywall cracking and nail popping, frequent 

causes of builder callbacks.

•	 ELIMINATE REDUNDANT FLOOR JOISTS. Double floor 

joists are often installed unnecessarily below non-load-bearing 

partitions. Nailing directly to the subfloor provides adequate 

attachment and support. Partitions parallel to overhead floor or 

roof framing can be attached to 2x3 or 2x4 flat blocking. 

•	 USE 2X3s FOR PARTITIONS. Interior, non-load-bearing 

partition walls can be framed with 2x3s at 24 inches on center or 

2x4 “flat studs” at 16 inches on center [2009 IRC R602.5]. 

For More Information on Advanced Framing

IBACOS. 2003. Best Practices: Optimum Value Engineering. Available on the Building 

America website at www.eere.energy.gov/buildings/building_america/pdfs/db/35380.pdf

Lstiburek, Joseph. 2005. “The Future of Framing Is Here,” Fine Homebuilding, 

November 2005, No. 174, p. 50-55.

NAHB Research Center. “Advanced Framing Techniques: Optimum Value Engineering 

(OVE),” Available at www.toolbase.org/Construction-Methods/Wood-Framing/advanceframing-techniques accessed 6-4-08

NRDC. 1998. Efficient Use of Wood in Residential Construction. Natural Resources Defense 

Council, Washington, D.C. www.nrdc.org/cities/building/rwoodus.asp

PATH. ToolBase Techspecs: Advanced Framing Techniques. 

www.toolbase.org/pdf/techinv/oveadvancedframingtechniques_techspec.pdf

Using single 2x4 headers instead of double 

2x6 headers in non-load-bearing walls 

allows space for insulation.

Ladder blocking where exterior walls 

intersect interior walls provides space for 

insulation and cuts back on thermal bridging.

Closed, insulated headers are one advanced 

framing technique. (Figure source: CARB)

Single top plate

Plywood sides 

with rigid insulation 

sandwiched inside

Plywood plate

2x4” 

header Maximum 8’ span

Insulate above 

headers

Max 2’ above 

header

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Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 7.3
DOE. 2002. Advanced Wall Framing. 6-page fact sheet by the U.S. Department of Energy 

www.nrel.gov/docs/fy01osti/26449.pdf

DOE. 2009. Advanced Framing, Article 1399, U.S. Department of Energy Building Energy Codes 

Resource Center, http://resourcecenter.pnl.gov/cocoon/morf/ResourceCenter/article//1399

Insulation

Insulation is usually hidden away behind finished surfaces, but insulation 

is the material that does the most to block heat loss through conduction. 

Insulation comes in a variety of forms; some of the common options are 

described below. Average R-values are provided in the table.

Common Insulating Materials (R-values per inch of insulation)

INSULATING MATERIAL Avg. R-Value 

per Inch

Fiberglass • Unfaced batt, standard density R-2.9 to R-3.8

• Unfaced batt, high density R-3.7 to R-4.3

• Blown fiberglass R-2.2 to R-2.7

Expanded 

Polystyrene (EPS)

• Rigid foam board R-3 to R-4

• Beads R-2.3

Extruded 

Polystyrene (XPS) • Rigid foam board R-5

Polyisocyanurate • Rigid board R-5.6 to R-8

• With foil facing R-7.1 to R-8.7

Polyurethane • Spray foam or foam board R-7 to R-9

• Foam board with foil facing R-7.1 to R-8.7

• Soy-based polyurethane spray foam R-3.7

Other • Cellulose, blown R-3.6 to 3.8

• Mineral wool, rock or slag, 

batt or loose

R-3.7

• Cotton batt R-3.4

• Sheep’s wool batt R-3.5

• Strawbale R-2.4

• Plastic PET R-3.8 to R-4.3

Source: DOE Energy Savers website: www.energysavers.gov/your_home/

insulation_airsealing/index.cfm/mytopic=11510

Two-stud corners with drywall clips 

use the least wood and give the best 

thermal performance.

Rural Development, Inc., achieved an R-42 

wall insulation value on homes in western 

Massachusetts by creating a double wall 

of two 2x4 16-inch on-center walls and 

stuffing the 11-inch cavity between the 

walls with dense-pack, dry-blown cellulose.

Conventional three-stud corner leaves 

a cavity that must be insulated by the 

framers—not good.

Improved three-stud corner allows 

insulation to be installed later, 

in sequence.

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7.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
BLANKETS OR BATTS: Blanket insulation in the form of batts 

or rolls is a flexible product made from mineral fibers, fiberglass, or 

textile fibers. Batts are available in widths suited to standard wall, 

floor, and attic framing spaces. Continuous rolls can be hand-cut 

and trimmed to fit. They are available with or without vapor retarder 

facings. Standard fiberglass batt insulation features R-values between 

R-11 (3.5-inch thick) and R-38 (12-inch thick). High-performance 

(medium- and high-density) fiberglass batts with greater R-values 

per inch of thickness are also available. If you choose to use other 

types of insulation, such as blown-in, batts can be installed in areas 

that may become inaccessible as construction unfolds; for example 

behind shower inserts, beneath stairs, or in rim joists. Batts also 

make good dams in attics around access points or other areas where 

blown-in insulation should be held back. Batts are not air barriers. 

Kraft facing forms a Class II vapor retarder. See Chapter 6 for more 

about vapor retarder code requirements in the cold climate. 

BLOWN-IN: Blown-in, loose-fill insulation includes loose fibers or 

beads that are blown into building cavities or attics using special 

pneumatic equipment. Netting may be stapled to studs to hold 

blown-in insulation in place before gypsum board is installed. 

Another form of blown-in insulation is fibers, such as cellulose 

made from recycled newspaper, that is mixed with a wet adhesive 

and sprayed into the wall cavity, then allowed to set in the walls 

making it resistant to settling. An advantage of blown-in insulation 

is that it easily takes the form of the cavity into which it is blown. 

Blown-in insulation will also fill spaces behind and around potential 

obstacles, such as electrical boxes, wiring, and plumbing. The 

blown-in material can provide some resistance to air infiltration if 

the insulation is sufficiently dense, but blown-in insulation should 

not be considered an air barrier.

SPRAY POLYURETHANE FOAM (SPF): Foamed-in-place 

polyurethane foam insulation can be applied by a professional 

applicator using special equipment to meter, mix, and spray the 

insulation into cavities where the foam hardens in place. Some 

polyurethane foams are made with up to 20% soy-based oil stock 

rather than 100% hydrocarbon-based oil. Sprayed foam makes an 

excellent air seal and can be used to reach hard-to-get-at places. 

Critical points where this type of foam is especially useful include 

complicated intersections of building elements with odd shapes 

and many joints. Other common areas include the rim joists at the 

intersection of the foundation and floor and between floors.

Spray foam comes with either an open-cell (OC SPF) or closed-cell 

(CC SPF) structure. An open-cell structure allows air to move between 

the cells within the insulation; water may be used as the blowing agent. 

(1) Batt insulation in ceiling. (2) Blown-in 

insulation. (3) Spray foam. (Photo source: 

Sam Garst). (4) Spray foam applied along 

the underside of the roof deck to provide a 

conditioned and non-vented attic space for 

ducts and air handlers.

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Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 7.5
Closed-cell foam is more rigid and dense with each cell forming a 

bubble that captures the gas inside of it. Closed-cell foam contains 

special gases that make it expand and give it greater R-values. Opencell foam is less dense, has a lower R-value rating, and is generally less 

expensive. Both types of foam are excellent air sealers. High-density, 

closed-cell foams have greater resistance to bulk liquid and vapor and 

may serve as both air and vapor barriers. Spray foam companies have 

converted to using a non-ozone-depleting blowing agent, but these 

agents may still have global warming potential.

RIGID FOAM INSULATION: Rigid insulation is made from fibrous 

materials or plastic foams that are pressed or extruded into sheets 

and molded pipe coverings. Rigid insulation provides thermal and 

acoustical insulation, strength with low weight, and coverage with few 

heat loss paths. Rigid foam insulating sheathing has other significant 

benefits, particularly in the areas of moisture control. Inwardly driven 

moisture from reservoir claddings such as brick and stucco can be 

controlled by rigid foam insulating sheathing. Code permits the use 

of rigid foam insulating sheathing of sufficient thickness in place of 

interior vapor barriers and vapor retarders, thereby enhancing the 

inward drying of the wall assembly; so that “double vapor barriers” 

can be avoided [2009 IRC 601.3, see IRC for R-values by IECC climate 

zone]. If sufficiently braced, walls can use rigid foam as an insulating 

sheathing in place of oriented strand board (OSB) and plywood 

sheathings for cost savings.

Rigid foam insulation sheets may be faced with a reflective foil that 

reduces radiant heat transfer when facing an air space. Foil facing 

also makes the board nearly impervious to water and vapor, so it 

should be used with caution. Rigid foam insulation may be used in 

combination with other insulation types, such as on the exterior of 

walls whose cavities are filled with cellulose or fiberglass. Foam sheets 

that may be in contact with the ground should be borate-treated for 

termite resistance. Rigid fiberglass insulation is used on the exterior of 

basement or foundation walls and can form a moisture screen. 

Rigid insulation sheets may be applied to the exterior of wall 

assemblies as insulating sheathing. This approach helps to seal air 

leaks, block thermal bridges where framing lumber spans the wall, 

provide a drainage plane or rain screen, and create additional R-value 

near the exterior surface of the wall. Insulation on the outside of 

the wall helps to temper the wall’s interior temperature and avoid 

condensation. Here is a summary of rigid insulation materials:

•	 Polyisocyanurate – 5.6 to 8.7 R-value per inch

Typically foil-faced rigid sheet; it should not be used in contact 

with soil because it absorbs moisture; foil facing is a vapor barrier 

“You really can’t overdo 

insulation. It is relatively cheap 

compared to other components 

of the house and you will pay for 

under-insulating for the life of 

the house.” 

Homebuilder Sam Garst

(top) Masonry walls are insulated with

interior rigid insulation.

(bottom) Sealing gaps between floor joists 

with spray foam provides a good air seal 

that prevents the flow of heat, cold, and 

pollutants from unconditioned space to 

conditioned space.

CHAPTER 7 / BUILDING AMERICA BEST PRACTICES SERIES

7.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
and should be used with caution; a non-ozone-depleting blowing 

agent is used (pentane).

•	 Extruded Polystyrene (XPS) – 5 R-value per inch

More consistent density and greater compressive strength than 

EPS; preferred material for soil contact or as rain barrier because 

it is resistant to liquid moisture penetration. The EPA deadline 

to switch to a non-ozone-depleting, VOC-free blowing agent was 

January 1, 2010. 

•	 Expanded Polystyrene (EPS) – 2.3 to 4 R-value per inch

EPS foam beadboard uses a non-ozone-depleting blowing agent 

(pentane). Spaces between beads can absorb water. It is not a 

vapor retarder. It is often used in structural insulated panels and 

insulating concrete forms; comes with borate treatment making 

it resistant to insects; requires a capillary break between soil and 

insulation; and comes in many densities and grades. 

•	 Fiberglass – 2.2 to 4.3 R-value per inch

Drainable and resistant to insect degradation; excellent for soil contact.

REFLECTIVE INSULATION SYSTEMS: Reflective insulation 

systems are fabricated from aluminum foils with a variety of backings 

such as roof sheathing, kraft paper, plastic film, polyethylene bubbles, 

or cardboard. The resistance to heat flow depends on the heat flow 

direction; this type of insulation is most effective in reducing downward 

heat flow and requires an air space adjacent to the reflective surface. 

There are no R-values for reflective insulation because R-values apply to 

conduction and reflective barriers reflect radiant heat. Reflective systems 

are typically located between roof rafters, floor joists, or wall studs. 

Reflective insulation placed in walls must be perforated. 

If a single reflective surface is used alone and faces an open space, 

such as an attic, it is called a radiant barrier. As a general rule, the 

reflective surface of a radiant barrier should face downward so that 

dust cannot collect on the surface. As the level of ceiling insulation 

increases, the value of a radiant barrier is diminished. In the cold 

and very cold climates where solar heat gain is less of an issue, 

reflective insulation is not necessary and installation of higher levels 

of attic insulation would be a more cost-effective way to get higher 

R-values. Radiant barriers should not be installed directly on top of 

attic floor insulation. In cold weather, a radiant barrier installed on 

the cold side of the insulation can act as a vapor barrier in the wrong 

location. When warm moisture carrying house air leaks into the 

attic in the winter, it may condense on the underside of the barrier. 

Even a perforated radiant barrier can trap moisture in cold climates 

since the water can freeze in the small holes and seal them. Because 

of these hazards, it is strongly recommended that you NOT apply 

(top) Bob Ward Companies used an 

exterior wall sheathing consisting of a 1/8-

inch layer of laminated fiberboard covered 

with 1/8-inch of extruded polystyrene 

foam board. This layer goes on the 

exterior side of the studs under the stone 

or wood siding. Joints are taped so the 

foam board serves as an air barrier as well, 

eliminating the need for housewrap. This 

exterior insulation layer moves the dewpoint surface to the outside of the framing 

member, reducing the potential 

for condensation and moisture damage 

within the wall cavity. (Photo source: 

Bob Ward Companies)

7.7

CHAPTER 7. THE OVERALL BUILDING ENVELOPE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 7.7
radiant barriers directly on top of the attic floor insulation. Installing 

them at all in a cold climate is not generally cost effective (DOE 2009).

For More Information on Insulation

ASHRAE. 2009. ASHRAE Handbook of Fundamentals. American Society of Heating, 

Refrigerating, and Air-Conditioning Engineers. www.ashrae.org/publications/page/158

Consortium for Advanced Residential Buildings. Steven Winter Associates (CARB-SWA). 

2009. Open-Cell vs Closed-Cell Foam Guide. www.carb-swa.com

ENERGY STAR. Builder Option Packages (BOPS) with recommended insulation levels 

by county. www.energystar.gov/index.cfm?c=bop.pt_bop_index

Florida Solar Energy Center (FSEC). 1988. Consumer Facts about Radiant Barriers. FSECFS-37-88. FSEC, Cocoa, FL. www.fsec.ucf.edu/en/publications/pdf/FSEC-FS-37-88.pdf

Krigger, John and Chris Dorsi. 2009. Resident Energy: Cost Savings and Comfort in Existing 

Buildings, 5th Edition, Prentice Hall (previous editions published by Saturn Resource Management).

Mathis, R.C. 2007. Insulating Guide. Building Science Press. Westford, MA. Available for 

purchase at www.eeba.org/bookstore/prod-Insulating-Guide-8.aspx

Parker, Danny and John Sherwin. 1998. “Comparative Summer Attic Thermal Performance 

of Six Roof Constructions.” TO-98-17-3. 1998 ASHRAE Annual Meeting, Toronto, Canada. 

www.fsec.ucf.edu/en/publications/pdf/FSEC-PF-337-98.pdf

Parker, Danny. 2001. FPC Residential Monitoring Project: New Technology Development 

Radiant Barrier Pilot Project. FSEC-CR-1231-01. Florida Solar Energy Center, Cocoa, FL. 

www.radiantbarrierdoneright.com/FSEC.pdf

Roos, Carolyn. 2008. Principles of Heat Transfer. WSUEEP07-004. Washington State 

University, Extension Energy Program, Olympia, WA. www.energy.wsu.edu/pubs/

U.S Department of Energy (DOE). 2009. “Cool Down with ‘Reflective Insulation’ Materials.” 

Setting the Standard. January 2009. DOE Building Energy Codes Program, 

www.energycodes.gov/publications/STS/2009/standard_january09.pdf

U.S. Department of Energy. 2009. “Radiant Barriers,” updated May 28, 2009, 

www.energysavers.gov.

U.S. Department of Energy (DOE). 2008. Insulation Fact Sheet. DOE/CE-0180. DOE’s 

insulation calculator for recommended insulation levels. www.ornl.gov/sci/roofs+walls/

insulation/ins_16.html 

U.S. Department of Energy (DOE). 1991. Radiant Barrier Attic Fact Sheet. DOE/CE-0335P. 

www.ornl.gov/sci/roofs+walls/radiant/rb_01.html

U.S. Department of Energy (DOE). “Recommended insulation levels by zip code.“ 

www1.eere.energy.gov/consumer/tips/insulation.html

Air Sealing

Unintentional air flow (through-wall penetrations, leaks around 

doors and windows, and cracks in the roof) robs a home of warm 

or cool air, serves as a pathway for moisture flow, and decreases 

comfort levels. Controlling air infiltration is one of the most 

cost-effective and simplest energy-efficiency measures in modern 

construction practices. Extensive air sealing is one of the primary 

40% improvement strategies. Air sealing is required by the 2009 

IECC 402.4, which identifies several areas for air sealing and requires 

verification with a blower-door test or visual inspection.

(top) Holes in the top plate for wiring are 

sealed with foam.

(middle) Unsealed holes for pipes can

leave large gaps for air and bugs to

pass through.

(bottom) Thorough air sealing and locating 

ducts in conditioned space are two ways 

the Loudon County Habitat for Humanity 

affiliate improves the efficiency of its homes. 

(Source: Loudon County Habitat for Humanity)

CHAPTER 7 / BUILDING AMERICA BEST PRACTICES SERIES

7.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Good caulking and sealing will reduce the infiltration of dust and 

dirt (and even bugs) that can enter homes through cracks and holes. 

The materials and approaches recommended here are common and 

time tested. However, these measures must be carefully installed to be 

effective and must be installed in the proper construction sequence 

before cavity areas are covered up by fixtures or walls. Health and 

safety are essential factors to consider when air sealing, especially if 

the home contains combustion appliances. See Building America’s 

Air Sealing guide for more information (www.buildingamerica.gov). 

Sealing against air leakage is primarily done for thermal reasons, 

but when coupled with appropriate mechanical ventilation, this 

procedure also assists in maintaining good indoor air quality for the 

occupant. This combination helps to provide controlled air rather 

than relying on pressure and temperature differences to supply air. 

Air leaks also carry water vapor; if this water vapor condenses, it 

can cause mold and other moisture problems. An important job for 

air barrier systems is separating garages from conditioned spaces to 

keep pollutants out of the house. 

The key to the control of airflow is the use of a continuous air barrier. 

This barrier may be made up of several types of materials as long as 

it provides an unbroken barrier between conditioned space (indoors) 

and unconditioned space (outdoors, attic, crawlspace, and garage). 

Typically mudded and taped gypsum board serves as an air barrier 

on the home’s interior. Alternatively, stucco or taped and caulked 

rigid foam may serve as an air barrier on the home’s exterior.

Building America researchers have worked with three building 

approaches that push the air and thermal barriers toward the exterior 

of the building shell: 1) conditioning crawlspaces and basements 

or using slabs, 2) installing insulated exterior sheathing, with sealed 

seams, and 3) conditioning attics. These approaches make it easier 

to provide an uninterrupted air barrier (see Chapter 14). 

The installation of high-efficiency furnaces and water heaters can 

also help control air leakage. Natural gas-fired condensing furnaces 

achieve combustion efficiency levels greater than 90%. These directvent furnaces and water heaters are sealed combustion systems that 

intake and exhaust air through plastic pipes that do not require a 

vertical chimney. Chimneys and flue chases are notorious for air 

and thermal leaks. A direct-vent fireplace can also eliminate the 

need for a chimney entirely. Ducts located in conditioned space 

eliminate penetrations through the building shell and avoid the 

intake of unconditioned air that can occur through duct leaks. 

More information on these systems is included in Chapter 9.

(top) Seams are caulked to provide a 

good air seal before installing insulation 

and dry wall.

(middle) Air sealing the wall between the 

garage and the home is vital for occupant 

health and safety.

(bottom) Framing is sequenced to install 

an air barrier of OSB, plywood, or rigid 

foam between the porch and the attic.

“There are plenty of ways to 

create a more energy-efficient 

home; solar power is one way, but 

insulation and a tight seal can go a 

long way to achieve this as well.”

Bob Walter, Morrison Homes, 

Elk Grove, California

7.9

CHAPTER 7. THE OVERALL BUILDING ENVELOPE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 7.9
The Thermal Bypass Checklist

The ENERGY STAR for Homes program has compiled the 

Thermal Bypass Checklist, a comprehensive list of potentially 

vulnerable spots in the building envelope. The checklist identifies 

25 points to inspect throughout the home, covering all major 

components of the building envelope including exterior walls, floors, 

ceilings, attics, and shafts. Builders can use the checklist to verify the 

integrity of the air barriers in the building envelope. The ENERGY 

STAR website contains the thermal bypass checklist and additional 

guidelines for installing insulation and air sealing. 

See the ENERGY STAR Qualified Homes Thermal Bypass Inspection Checklist

on the previous page.

For More Information on Air Sealing

2009 IECC. 2009. International Energy Conservation Code, Section 402.4 “Air Leakage,” 

International Code Council (ICC), Washington, DC. www.iccsafe.org/Store/Pages

DOE. 2010. Retrofit Techniques and Technologies: Air Sealing, PNNL-19284, U.S. Department 

of Energy, http://www1.eere.energy.gov/buildings/building_america/

ENERGY STAR. 2008. “Thermal Bypass Checklist” www.energystar.gov/ia/partners/bldrs_

lenders_raters/downloads/Thermal_Bypass_Inspection_Checklist.pdf

ENERGY STAR. 2008. “ENERGY STAR Qualified Homes: Thermal Bypass Checklist Guide,” 

ENERGY STAR. www.energystar.gov/ia/partners/bldrs_lenders_raters/downloads/TBC_

Guide_062507.pdf

Lstiburek, Joseph. 2006. Building Science Digest 104: Understanding Air Barriers. Building 

Science Press, Waterford, MA. Available at www.buildingscience.com/documents/digests/

bsd-104-understanding-air-barriers

Lstiburek, Joseph. 2010. Guide to Attic Air Sealing, prepared by Building Science 

Corporation for the U.S. Department of Energy Building America Program. 

www.buildingscience.com/documents/primers/Attic%20Airsealing%20Guide%20-%20

BSC%20Draft%20-%202010-02-12.pdf/view

Builder David Sullivan and the South 

Chicago Workforce worked with Building 

America on the first structural insulated 

panel (SIP) home project ever permitted in 

the City of Chicago. SIPS provide excellent 

air sealing and insulating properties with 

fewer seams to caulk and much less thermal 

bridging than typical stud construction.

CHAPTER 7 / BUILDING AMERICA BEST PRACTICES SERIES

7.10 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Posted 06/02/08

ENERGY STAR Qualified Homes

Thermal Bypass Inspection Checklist 

Home Address: City: State: .

Thermal Bypass Inspection Guidelines Corrections 

Needed 

Builder

Verified

Rater

Verified N/A 

Requirements: 

Insulation shall be installed in full contact with sealed interior and exterior air barrier except for alternate to interior air barrier 

under item no. 2 (W lls Adjoining Exterior Walls or Unconditioned Spaces) a

All Climate Zones:

1.1 Overall Alignment Throughout Home    

 1.2 Garage Band Joist Air Barrier (at bays adjoining conditioned space)    

 1.3 Attic Eave Baffles Where Vents/Leakage Exist    

Only at Climate Zones 4 and Higher: 

 1.4 Slab-edge Insulation (A maximum of 25% of the slab edge may be 

uninsulated in Climate Zones 4 and 5.)    

Best Practices Encouraged, Not Req’d.:

 1.5 Air Barrier At All Band Joists (Climate Zones 4 and higher)    

1. Overall Air Barrier 

and Thermal 

Barrier Alignment 

 1.6 Minimize Thermal Bridging (e.g., OVE framing, SIPs, ICFs)    

Requirements: 

• Fully insulated wall aligned with air barrier at both interior and exterior, OR

• Alternate for Climate Zones 1 thru 3, sealed exterior air barrier aligned with RESNET Grade 1 insulation fully supported 

• Continuous top and bottom plates or sealed blocking

 2.1 Wall Behind Shower/Tub    

 2.2 Wall Behind Fireplace    

 2.3 Insulated Attic Slopes/Walls    

 2.4 Attic Knee Walls    

 2.5 Skylight Shaft Walls    

 2.6 Wall Adjoining Porch Roof    

 2.7 Staircase Walls    

2. Walls Adjoining 

Exterior Walls or 

Unconditioned

Spaces

 2.8 Double Walls    

Requirements: 

• Air barrier is installed at any exposed fibrous insulation edges 

• Insulation is installed to maintain permanent contact with sub-floor above including necessary supports (e.g., staves for 

blankets, netting for blown-in) 

• Blanket insulation is verified to have no gaps, voids or compression. 

• Blown-in insulation is verified to have proper density with firm packing 

3.1 Insulated Floor Above Garage    

3. Floors between 

Conditioned and 

Exterior Spaces 

3.2 Cantilevered Floor    

Requirements: 

Openings to unconditioned space are fully sealed with solid blocking or flashing and any remaining gaps are sealed with 

caulk or foam (provide fire-rated collars and caulking where required)

4.1 Duct Shaft 

4. Shafts 

  

4.2 Piping Shaft/Penetrations    

4.3 Flue Shaft    

Requirements:

• All attic penetrations and dropped ceilings include a full interior air barrier aligned with insulation with any gaps fully sealed

with caulk, foam or tape 

• Movable insulation fits snugly in opening and air barrier is fully gasketed

5.1 Attic Access Panel (fully gasketed and insulated)    

5.2 Attic Drop-down Stair (fully gasketed and insulated)    

5.3 Dropped Ceiling/Soffit (full air barrier aligned with insulation)    

5.4 Recessed Lighting Fixtures (ICAT labeled and sealed to drywall)    

5. Attic/ Ceiling 

Interface

5.5 Whole-house Fan (insulated cover gasketed to the opening)    

Requirements: 

Gap between drywall shaft wall (i.e., common wall) and the structural framing between units is fully sealed at all exterior 

boundary conditions

6. Common Walls 

Between Dwelling 

Units

6.1 Common Wall Between Dwelling Units    

Home Energy Rating Provider: _______________________ Rater Inspection Date: _______________ Builder Inspection Date: _______________ 

Home Energy Rater Company Name: ___________________________ Builder Company Name: _______________________________________ 

Home Energy Rater Signature: ________________________________ Builder Employee Signature:_____________________________________

7.11

CHAPTER 7. THE OVERALL BUILDING ENVELOPE

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 7.11
In its simplest form, building envelopes are cubes that incorporate 

three parts: the floor, four walls, and a roof. In actuality, these 

assemblies are complicated combinations of rectangles, triangles, 

and even domes. Building homes that deliver comfort, durability, 

and energy performance requires paying attention to the details of 

each assembly. This chapter provides guidance on controlling liquid 

and water vapor, air flow, and heat flow in the foundation, wall, 

and roof assemblies.

Foundation Assemblies 

Slab, crawlspace, and basement foundation types are all common 

in the cold climate. The foundation forms the solid underpinning 

for a house’s structural integrity. It also provides the boundary 

between the house and the ground, preventing the unwanted transfer 

of moisture, air, heat, and soil gases from the ground to occupied 

living spaces. It plays an important role in building durability 

and occupant health as well as in building energy efficiency. See 

Chapter 14 for detailed foundation drawings that show measures for 

controlling moisture, air, and heat flow. 

Controlling Liquid Water in Foundations

Proper site grading directs surface water away from building 

foundations and walls. The steeper the slope away from the building, 

the better the water will drain. All building foundations should be 

designed and constructed to prevent the entry of moisture. 

Most foundation water leakage or intrusion is due to either bulk 

moisture leaks or capillary action. Bulk moisture is the flow of liquid 

water. Capillary action occurs when water wicks or is absorbed into 

Chapter 8.

Building Envelope 

Sub-Assemblies

CHAPTER TOPICS

8.1 Foundation Assemblies

8.14 Wall Assemblies

8.22 Roof Assemblies

8.27 Window and Door Assemblies

Drain all water away

from the structure

(Figure adapted from 

Building Science Corporation)

Drain Wall

Drain Roof

Drain Building

Drain Site

Drain Ground Drain Ground

Drain Site

Drain Materials

Drain Components

Drain Openings

8.1

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.1
small cracks and pores in building materials, such as masonry block, 

concrete, or wood. Moisture can also be carried by soil gas into the 

home. Moisture may cause structural decay and can contribute to 

human health problems. 

The following practices apply to all foundation systems.

•	 Design the house structure with overhangs, gutters, drainage 

planes, and flashing to shed rainwater and conduct it away from 

the house [as required in 2009 IRC R703.1 and R703.8].

•	 Slope top soil to drain away from the house. [2009 IRC R401.3 

requires that the lot be graded to fall at least 6 inches in the first 10 

feet from the foundation.] Building America recommends a surface 

grade of at least 5% for at least 10 feet around and away from the 

entire structure.

•	 Drain driveways, garage slabs, patios, stoops, and walkways away 

from the structure. [IRC 2009 R401.3 requires that impervious 

surfaces within 10 feet of the building foundation be sloped at least 

2% away from the building.]

•	 Keep all untreated wood away from contact with earth and 

concrete. Keep wood and fiber cement siding at least 8 inches from 

the soil surface to minimize damage from rain splashing up from 

ground surface.

•	 Install a protective shield such as a plastic L bracket, gasket, or 

water-proof membrane between foundation wall stem and sill 

plate to keep capillary water from wicking into the wall from the 

foundation. Metal flashing can also serve this function and serve 

as a termite shield [2009 IRC R318.3].

•	 Damp-proof all below-grade portions of the exterior concrete 

foundation walls [2009 IRC R406]. 

•	 Cover exposed earth in crawlspace floors with 6-mil polyethylene 

sheeting. All joints of the vapor retarder shall overlap by 6 inches 

and be sealed or taped. The edges of the vapor retarder shall extend 

at least 6 inches up the stem wall and shall be attached to the stem 

wall. [2009 IECC 402.2.9 and 2009 IRC 408.3 require vapor retarder 

over exposed earth in unvented crawlspaces only.]

In addition to these code requirements, Building America makes the 

following recommendations for foundation moisture management:

•	 Damp proof the exposed portion of the foundation with latex 

paint or other sealants. 

(top) Make sure the downspouts are 

continuous to the ground and extend to at 

least 3 feet from the house. Install flashing 

at the roof valleys and edges and install rain 

gutters to guide water off the roof and away 

from the house. (Photo Source: EPA, photo 

by Terry Brennan)

(middle) This foundation moisture 

management approach uses a dimpledplastic drainage plane and damp proofing 

on the exterior side of the foundation wall. 

Landscape filter fabric keeps soil from 

clogging the gravel around a perforated 

drainage pipe that runs along the outside 

of the footing. A gasket keeps moisture 

from migrating up through the footing into 

the treated sill plate.

(bottom) Here, a damp proof coating 

and exterior rigid fiberglass insulation are 

applied to the foundation wall below grade.

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
•	 Apply a protective coating over rigid foam exterior foundation 

wall insulation at above-grade applications. Examples of protective 

coverings include flashing, fiber-cement board, parging, treated 

plywood, or EPDM membrane. 

•	 Place a continuous drainage plane or free-draining materials over 

the damp proofing or exterior insulation on foundation walls to 

channel water to the foundation drain and relieve hydrostatic 

pressure. Drainage plane materials include impervious plastic 

mats, high-density fiberglass foam insulation boards, and 

uniformly graded gravel.

•	 Place slabs and crawlspace floors above the surrounding grade. 

•	 Treat footings poured independent of slabs or foundation walls 

with a bituminous damp-proof coating, masonry capillary-break 

paint, or a layer of 6-mil polyethylene plastic to isolate the footing 

from the remainder of the assembly.

•	 Place 6-mil polyethylene sheeting or rigid foam insulation directly 

beneath the slab or basement floor. Wrap sheeting continuously 

over the slab and footings up to grade [per 2009 IRC R406.3.2].

•	 Do not place a sand layer between the vapor retarder and the 

concrete slab or basement floor. Differential drying and cracking 

is better handled with a low water-to-concrete ratio and wetted 

burlap covering during initial curing.

•	 Place a 4-inch-deep, 3⁄4-inch gravel bed directly beneath the 

polyethylene sheeting to act as a capillary break and drainage pad.

•	 Install a perimeter drain below the drainage plane along the side 

(not on top of) footings for all basements and crawlspaces where 

the floor is below grade. 

•	 Ensure that the lowest excavated site foundation level is above 

the local groundwater table at its maximum elevation 

[per 2009 IRC R408.6].

•	 Place drainage systems below basement floors.

Frost Heave and Adfreeze

Frost heave occurs when ice crystals form from water at the freezing 

plane of soil that is saturated. As the water is pulled up into ice 

crystals, the ground below dries drawing in more water from the 

surrounding soil, which is in turn drawn up into ice crystals, thus 

creating an upward thrust of soil and ice. The concern is that this 

Davis Energy Group of the CARB Building 

America team developed a method for 

insulating slab perimeters. The method, 

which is commercially available, uses 

termiticide-treated rigid foam insulation 

encased in PVC as the form for the 

concrete foundation. In cold climate 

locations, the forms can be stacked to 

provide deeper protection against frost 

(Personal communication with David 

Springer, Davis Energy Group, 11/10/10).

Detail of insulating form for slab perimeters. 

(Source: Davis Energy Group)

8.3

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.3
expanding soil and ice, or frost heave, will push against building 

foundations causing them to crack and buckle. However, frost 

expansion always follows the direction of heat loss. So expansion 

will be up and away from the building foundation if the basement 

is heated. According to Joseph Lstiburek at Building Science 

Corporation, several years of investigative work by the Canadian 

Department of Energy, Mines, and Resources found no evidence 

of frost-damaged foundations in homes with heated basements, 

regardless of whether the walls were insulated or uninsulated, and 

regardless of whether the insulation is on the interior or exterior 

of the wall (Lstiburek 2011). In insulated basements heat loss is 

greatly reduced but the direction of heat loss remains outward, 

and frost direction will follow the direction of heat loss. Another 

concern is adfreeze, or adhesion freezing, where saturated soil freezes 

against a foundation wall, adhering to it and lifting the wall when 

it heaves upward. Fortunately water molecules also migrate in the 

direction of heat loss so, in cold soil, water will migrate away from 

the foundation wall of a heated basement, reducing the strength of 

adhesion bonds and the likelihood of damage. Lstiburek notes that 

this is again true in insulated as well as uninsulated basements as 

long as they are heated (Lstiburek 2011).

If you don’t want to heat the basement, you can lay a skirt of R-10 

rigid insulation around the perimeter of the building laid several 

inches below ground that extends horizontally a distance equal to the 

average frost depth. A better option is to avoid frost-susceptible soils 

and water saturation at the foundation. Use granular soil, not fine 

or silty soil for backfill along the foundation and provide good site 

grading and perimeter drainage as described above (Lstiburek 2011).

•	 Place footings below frost depth.

•	 Use gravel with no more than 3% grains finer than 0.02 mm. Don’t 

use clays, silts, tills, or very fine-grained sand as a backfill because 

they are susceptible to frost action.

•	 Prevent saturation of soil at foundation by grading site and 

providing perimeter drainage at footing.

Controlling Water Vapor in Foundations

Water vapor from basement and slab foundations can be controlled 

using the techniques described above. In vented crawlspaces the 

dominant source of moisture is bulk water, not water vapor from 

indoor or outdoor air condensing in the crawlspace. Water enters 

the crawlspace because of improper irrigation practices, ground 

slope, rain runoff, high groundwater tables, rain and snow during 

the construction process, and leaks in plumbing (Baker and Murray 

2006). These sources can be controlled by careful site grading, 

Unvented, insulated crawlspaces are 

recommended in the cold climate in the 

eastern and midwestern United States, 

where high humidity levels can cause 

moisture problems in vented crawlspaces.

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
installation of drainage systems, proper foundation design and 

water-proofing measures, appropriate landscaping, and other 

measures listed above. 

Some moisture in crawlspaces occurs from soil vapor. To control 

water vapor from soil in crawlspaces, do the following:

•	 Install 6-mil polyethylene across the entire ground surface. 

•	 Overlap all seams by 12 inches and tape. 

•	 Seal the polyethylene to the walls with pressure-treated wood 

strapping nailed at least 6 inches up the walls or to a height equal 

to ground level [2009 IECC 402.2.9]. 

Some Building America teams recommend installing one polyethylene 

groundcover at the beginning of construction; then, when 

construction is completed, installing a second sheet to cover any rips 

in the first one and sealing it to the walls. To improve durability, a 

minimum 2-inch concrete slab can be poured over the polyethylene.

In some parts of the country, the condensation of water vapor due 

to temperature differences in vented crawlspaces can be a significant 

source of crawlspace moisture. In the Midwest and eastern half of 

the country, where summers are humid, moisture can be carried 

into the crawlspace in the air drawn through open foundation wall 

vents. When this warm, moist air reaches cooler structural framing, 

the moisture condenses onto the framing and can cause mold and 

structural problems. In winter, cold air is drawn into the crawlspace 

and does little to dry out crawlspaces, but can lower temperatures, 

cause condensation on warm floor joists, and freeze exposed 

waterpipes. In these climate conditions, which are common east 

of the Mississippi, Building America research teams recommend 

sealing, insulating, and conditioning the crawlspaces.

In the west, summers are dry and winters north of the hot-dry 

climate zone are heating-dominated so relative humidity in vented 

crawlspaces is likely to stay low enough throughout the year to avoid 

condensation-related moisture problems. Building America research 

done in a cold, dry location in eastern Washington State regarding 

the value of vented versus unvented crawlspaces seemed to indicate 

either method could be acceptable depending on the specific location 

of the house being built (in a high radon area or not) and specific 

circumstances of the home (ducts in the crawlspace or not). High 

radon levels were found in the crawlspaces of two homes in the study 

with unvented crawlspaces but power venting of the crawlspace with 

a fan kept radon levels inside the home below the EPA threshold 

of 4 pCi/L (Nordeen 2008; Dave Hales, WSU Energy Extension 

Program, personal communication October 2009). 

8.5

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.5
Sealed, conditioned crawlspaces offer non-energy advantages over 

vented crawlspaces that are worth considering such as minimizing 

the risk of freezing pipes, cold floor complaints, bulk water 

intrusion, and pest intrusion. While unvented crawlspaces can 

provide a better environment for HVAC equipment than a vented 

crawlspace, the best practice is to locate the furnaces and ducts in 

conditioned space. Ducts that are located in the crawlspace must be 

mastic sealed. In areas with high radon levels, mitigation measures 

should be installed in unvented crawlspaces, including gravel under 

the slab and installation of a radon/soil gas vent stack, with an 

electric fan for power venting if necessary. 

Unvented crawlspaces are allowed in the 2009 IRC R408.3 as long as the 

exposed earth is covered with a Class 1 vapor retarder that is overlapped 

at edges, taped, and sealed to walls; the walls are insulated; and the 

crawlspace is mechanically vented with an exhaust fan or supplied with 

conditioned air and a return duct. Check for any state restrictions

For More Information on Foundation Moisture Control

Baker, Ken, and Chuck Murray. 2006. Crawlspace Issues in the Northwest. Washington State 

University Extension Energy Program. www.kenergy.us/pdf/Regional%20Crawlspace_final.pdf

Building Science Corporation, Crawlspace Insulation, Information Sheet 512.

www.buildingscience.com/documents/information-sheets/5-thermal-control/crawlspaceinsulation/?searchterm=512

Burn, K.N. 1976. Frost Action and Foundations, CBD-182, Canadian Building Digests, National 

Research Council Canada, www.nrc-cnrc.gc.ca/eng/ibp/irc/cbd/building-digest-182.html.

EPA. Consumer’s Guide to Radon Reduction. U.S. Environmental Protection Agency 

www.epa.gov/radon/pubs/consguid.html

EPA. 2010. “Technical Guidance to the Indoor airPLUS Construction Specification: 

1. Moisture Control - Water-Managed Roof Assemblies,” www.epa.gov/indoorairplus/

technical/moisture/1_7.html

Journal of Light Construction. 1997. “Troubleshooting Guide to Residential Construction.” 

The Journal of Light Construction, Ed. Steven Bliss, Williston, Vermont.

Lstiburek, Joseph. 2004. Builders Guides. Guides to mixed humid, hot-dry, mixed-dry, 

and cold climates, available for purchase at www.eeba.org/bookstore. 

Lstiburek, Joseph. 2006. EEBA Water Management Guide, available for purchase at 

www.eeba.org/bookstore/prod-Water_Management_Guide-9.aspx 

Lstiburek, Joseph. 2008. Concrete Floor Problems, BSI-003, Building Science.com. 

www.buildingscience.com/documents/insights/bsi-003-concrete-floor-problems 

Lstiburek, Joseph. 2011. Double Rubble Toil and Trouble, Insight 045, Feb. 2011, Building 

Science Corporation, www.buildingscience.com/documents/insights/bsi-045-doublerubble-toil-trouble/

Lubliner, Michael, Larry Palmiter, David Hales, and Andrew Gordon. 2007. “Crawlspace 

Design in Marine and Cold Climates,” in Thermal Performance of the Exterior Envelopes of 

Buildings X, Proceedings of ASHRAE THERM X, Clearwater, FL, Dec. 2007. 

www.ornl.gov/sci/buildings/2010/Session%20PDFs/96_New.pdf 

Nordeen, Gary. 2008. Unvented Crawl Spaces, Washington State University Extension 

Energy Program, www.energy.wsu.edu/pubs/

Robinsky, I., and K. E. Bespflug, 1973. “Design of Insulated Foundations.” J. Soil Mech. 

Found. Eng., A.S.C.E., Vol. 99, SM9, p. 649-667.

Prepare Your Site for 

Good Drainage

New Tradition Homes of Vancouver, 

Washington, does extensive site 

preparation to ensure good drainage. For 

homes with crawlspaces, they will raise and 

grade building sites so that all crawlspaces 

can drain to daylight. Excavators dig out 

the crawlspace, grade it flat, then dig out 

a sloped trench diagonally across the 

crawlspace that exits to a low-point drain 

sleeve with a one-way valve to let water 

out but not in. This drain sleeve directs the 

water to an infiltration system (a drywell) 

or out to the street via a curb cut. 

Once the sloped trench is dug, 4 to 6 

inches of crushed rock are laid over the 

entire crawlspace and foundation area. 

Next, the concrete footing, stem, and 

foundation are poured on top of the 

rock. When the house is complete, 6-mil 

visquene is laid over the crawlspace 

ground. This can be covered with a 

concrete slab that is sloped to drain to 

the low point drain where water can 

exit to daylight. 

“When water finds its way into the 

crawlspace because of our persistent rains, 

it has a natural channel to flow out via the 

low-point drain,” said Steve Tapio, head of 

New Tradition’s in-house building science 

team. On foundation walls, the builder 

adds damp proofing, dimpled plastic 

drainage sheets, and a perimeter drainage 

pipe if there is living space below grade.

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Controlling Air Infiltration in Foundations

The greatest challenges for air sealing are at the intersections of 

different building assemblies. [The 2009 IECC 402.4 requires air sealing 

of the building thermal envelope at rim joists, utility penetrations, and 

other areas.] Building America recommends the following foundation 

air sealing techniques:

•	 Install a sill gasket between the concrete foundation wall and the 

bottom plate to control air infiltration and to serve as a capillary break.

•	 Seal all panel joints to stop air leakage through subfloor sheathing 

installed over unconditioned spaces such as vented crawlspaces, 

unconditioned garages, or cantilevered floors over exterior walls.

•	 Use two-part spray foam to air seal and insulate at the sill plate, 

forming a continuous seal at the subfloor-rim joist-sill plate interface.

Controlling Heat Flow in Foundations

Insulation techniques for slab, crawlspace, and basement foundations 

are described below.

Slab Foundation Insulation 

Slabs in the cold climate should be insulated at the perimeter with 

borate-treated foam board or rigid fiberglass insulation approved 

for below-grade use. [The 2009 IECC 402 requires a slab R value of 

R-10 on the interior or exterior side of the foundation wall, plus an 

additional R-5 if the slab is heated (i.e., contains radiant heating coils) 

in the cold climate. This insulation must extend down vertically and 

out from the exterior or in from the interior a total of 2 feet in IECC 

climate zone 5 or 4 feet in IECC climate zones 6 or 7.] Building America 

recommends that rigid insulation be placed on the interior side 

of the stem wall from the slab to the top of the footing. Building 

America recommends that an R-10 layer of rigid foam insulation 

extend underneath the entire slab, whether or not the slab is heated, 

in the cold climate. This provides additional moisture control and 

minimizes the likelihood of condensation and mold in carpeting and 

floor coverings over an uninsulated floor. 

Some code officials may require a gap between exterior insulation 

and wood foundation elements to provide a termite inspection 

area. Exterior insulation should be applied from the top of the 

foundation wall to the bottom of the frost line. The exterior face of 

the insulation exposed to outside air should be covered with flashing, 

fiber cement board, parging (stucco type material), treated plywood, 

or EPDM membrane material.

Code/Above Code 

Insulation for Slab on Grade 

A comparison of the 2009 IECC 

climate zones 5–8, and Building America 

recommendations

Code

2009 IECC Slab Edge Insulation, 

Vertical Extension 

IECC 5 Unheated R-10, 2 ft

Heated* R-15

IECC 6 Unheated R-10, 4 ft

Heated* R-15, 4 ft

IECC 7&8 Unheated R-10, 4 ft

Heated* R-15, 4 ft

Above Code

Building America 

Recommendations

Unheated

R-15 rigid foam at 

perimeter, exterior 

or interior

Heated*

R-15 perimeter plus R-10 

underneath entire slab

* Heated slab refers to a slab floor containing 

radiant floor heating coils. Location of 

insulation is between the heated slab and 

the foundation wall. Vertical insulation 

extends down from top of slab and can 

extend down, down and in under the slab, 

or down and out from the building the 

number of feet designated. 

8.7

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.7
In cold climates, the primary slab-on-grade approach involves 

stem wall and footing construction to locate the bottom portion 

of the foundation below the frost depth. Shallow, frost-protected 

foundation insulation approaches are not recommended for 

production builders due to the likelihood of damage to pieces of 

rigid insulation laid horizontally out from the building.

For More Information on Slab Foundations 

Building Science Corporation. 2004. Houses that Work. www.nrel.gov/docs/fy04osti/34585.pdf

The American Society of Civil Engineers. Standard 32-01: 

Design and Construction of Frost-Protected Shallow Foundations. 

University of Minnesota, Building Foundations Research Program, 

Frost Protected Shallow Foundations Design Specifications. 

www.buildingfoundation.umn.edu/MHFAfrostFoundation.htm 

Building Science Corporation. 2009. Slab Edge Insulation, Information Sheet 513, 

www.buildingscience.com/documents/information-sheets/5-thermal-control/slab-edge-insulation/

Crawlspace Insulation 

Two methods are in use for insulating crawlspaces. The first, in 

common use over the last several decades, is to insulate the underside 

of the building floor and locate screened vents above grade in the 

foundation walls to provide the unconditioned crawlspace with 

ventilation. With ventilated crawlspaces, it is essential to air seal and 

properly insulate the underside of the first floor and tightly seal and 

insulate any ducts located in the crawlspace. [2009 IECC 402 requires 

R-30 floor insulation in IECC climate zones 5 and 6 and R-38 insulation 

in climate zones 7 and 8, or at least enough to fill the framing cavity to 

a minimum of R-19.] Research has shown that vented crawlspaces can 

have moisture problems, especially in areas with frigid winter air or 

warm, humid summer air (Building Science Corporation 2009). 

Another approach [permitted by 2009 IECC 402.2.9] is referred to as 

conditioned crawlspaces, or mechanically vented crawlspaces. With 

this type of system, foundation side walls are insulated on either the 

interior or exterior (or both) and no passive outside air vents tunnel 

through the foundation wall. [2009 IECC 402 requires R-10 rigid foam 

on interior or exterior or R-13 cavity insulation on interior in IECC climate 

zones 5, 6, 7, and 8.] Unvented, conditioned crawlspaces can provide 

a conditioned space for ducts and air handlers, although best 

practice is not to place HVAC equipment in the crawlspace. 

When insulating a conditioned crawlspace, some Building America 

researchers recommend installing insulation on the exterior side 

of the foundation wall. Exterior insulation will help to protect the 

foundation from the freeze-thaw cycle and a warmer wall is less likely 

to condense moisture. Products such as borate-treated foam board or 

rigid fiberglass insulation work well. Extruded polystyrene (R-5 per 

inch) is durable and moisture resistant. Expanded polystyrene (R-4 

Code/Above Code 

Floor Insulation for 

Vented Crawlspaces and 

Unconditioned Basements 

A comparison of the 2009 IECC climate 

zones 5–8 and Building America 

recommendations

Code

2009 IECC

Floor insulation shall 

maintain permanent 

contact with underside 

of subfloor decking 

IECC 5 R-30*

IECC 6 R-30*

IECC 7&8 R-38*

Above Code

Building America 

Recommendations

R-30* under floor deck, 

recommend full spray 

foam or flash spray 

foam to air seal and 

insulate, especially at 

rim joists. 

*Or insulation sufficient to fill the 

framing cavity, R-19 minimum.

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
per inch) is less expensive, but it has a lower insulating value. Rigid fiberglass insulation does not insulate as well as 

foam but provides a drainage plane. Some code officials may require a gap between exterior insulation and wood 

foundation elements to provide a termite inspection area. Insulation that is exposed above grade must be covered 

with a protective coating such as flashing, fiber cement board, parging (stucco type material), treated plywood, or 

EPDM membrane material. [The 2009 IRC 406 requires damp proofing of the foundation wall below grade.]

If placed on the interior of a conditioned crawlspace, wall insulation must extend

down the wall to a depth at least 2 feet below grade level [2009 IECC 402.2.9]

and be rated for crawlspace and basement exposure. Polyisocyanurate 

rigid foam insulation with an aluminum facing is a good interior 

insulation choice and has an R value of R-7.1 to R-8.7 per inch. 

If the crawlspace wall extends less than 2 feet below grade level, 

then the remaining insulation must be placed horizontally 

along the ground at the base of the wall.

For more information on 

Crawlspace Insulation: 

Broniek, John. Builder System 

Performance Packages Technical 

Report. Prepared by IBACOS for the 

Building America Program. 

www.buildingamerica.gov

Building Energy Codes Resource 

Center, Details for Mechanically 

Vented Crawlspaces - Code Notes, 

http://resourcecenter.pnl.gov/cocoon/

morf/ResourceCenter/article//131

(includes information on sizing the 

mechanical ventilation). 

Building Science Corporation. 2009. 

Crawlspace Insulation, Information 

Sheet 512. www.buildingscience.com/

documents/information-sheets/5-

thermal-control/crawlspace-insulation

U.S. EPA. 1995. Passive Radon Control 

System for New Construction, EPA 402-

95-012, U.S. Environmental Protection 

Agency, www.epa.gov/radon/rrnc/

moreinfo.html

Yost, Nathan. May 2003. “The Case for 

Conditioned, Unvented Crawlspaces.” 

Building Safety Journal. www.

buildingamerica.gov

www.crawlspaces.org

Building Science Corporation 

recommended this wall detail for 

this home in Aspen, Colorado, that 

has a sealed, insulated crawlspace. 

Additional wall schematics for other 

cold climate locations are shown 

in Chapter 14. (Source: Building 

Science Corporation).

8.9

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.9
Basement Insulation 

Basements are a common foundation system in the cold climate. 

Wall insulation in basements is similar to that described for 

crawlspaces. Basement floors are insulated in the same way as slabs. 

[2009 IECC 402 requires R-10 rigid foam on the interior or exterior 

surface of the walls or R-13 cavity insulation on interior basement walls in 

IECC climate zone 5. In IECC climate zones 6, 7, and 8, the requirement is 

R-15 continuous rigid foam insulated sheathing on the interior or exterior, 

or R-19 interior cavity, or R-5 exterior plus R-13 cavity insulation. In IECC 

climate zone 5, R-10 slab floor edge insulation is required extending 2 

feet horizontally under the slab or out from the building. In IECC zones 6, 

7, and 8, this increases to R-15 and 4 feet.]

Insulating basement walls, whether on the interior or exterior, 

does not make the walls more likely than uninsulated walls to be 

damaged by frost heave or adfreezing (Lstiburek 2011). Placing rigid 

insulation on the exterior sides of basement walls is one method 

for insulating the basement (Broniek 2003; Yost and Lstiburek 

2002). Exterior insulation will help to protect the basement wall 

from freeze-thaw cycles and will help make the wall warmer, giving 

condensation less chance of forming and improving thermal comfort. 

Exterior wall insulation must be approved for below-grade use. Products 

such as borate-treated foam board or rigid fiberglass insulation work 

well. Extruded polystyrene (R-5 per inch) is durable and moisture 

resistant. Expanded polystyrene (R-4 per inch) is less expensive, but 

it has a lower insulating value. Rigid fiberglass insulation does not 

insulate as well as foam but it is the only insulation option that provides 

a drainage plane for foundation walls. Some code officials may require 

a gap between exterior insulation and wood foundation elements to 

provide a termite inspection area. Insulation that is exposed above grade 

must be covered with a protective coating such as flashing, fiber cement 

board, parging (stucco type material), treated plywood, or membrane 

material. Exterior insulation is an especially good choice in areas with 

high water tables or poorly draining soils. 

One builder in Aspen, Coloroado, Shaw Construction, who worked on 

a Building America project described in this report, insulated basement 

floors with high-density, closed-cell spray foam that was sprayed 

directly onto the 4-inch layer of gravel under the foundation slab. The 

foam layer was about 4 inches thick, providing approximately R-28 

of insulation. Because the foam was closed cell, it served as a vapor 

barrier as well. If the basement space was to be unheated, the slab 

was fully insulated with spray foam underneath. All heated basements 

were insulated from the perimeter to about 2 to 3 feet in under the 

slab. Interior basement walls were insulated with R-13 (2 inches) of 

polyisocyanurate on the interior of the basement walls.

Code/Above Code 

Wall Insulation for Conditioned 

Crawlspaces and Conditioned 

Basements 

A comparison of the 2009 IECC climate 

zones 5–8, and Building America 

recommendations

Code

2009 IECC

IECC 5 R-10/13*

IECC 6 R-15/19*

IECC 7&8 R-15/19*

Above Code

Building America 

Recommendations

Exterior

Exterior of foundation 

wall insulated with R-21 

of rigid fiberglass or 

borate treated XPS

Interior 

Interior of foundation 

wall insulated with R-21 

of rigid fiberglass, rigid 

EPS or XPS foam, or 

poly-iso spray foam

* For a conditioned crawlspace, mechanical 

ventilation to the outside is recommended 

where there are high radon or soil gas 

concentrations. 

Per 2009 IECC, 15/19 means R-15 continuous 

insulated sheathing on the interior or exterior 

of the home or R-19 cavity insulation at the 

interior of the basement wall. “15/19” can be 

met with R-13 cavity insulation on the interior 

of the basement wall plus R-5 continuous 

insulated sheathing on the interior or exterior 

of the home. 10/13 means R-10 continuous 

insulated sheathing on the interior or exterior 

of the home or R-13 cavity insulation at the 

interior of the basement wall. 

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.10 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
If interior insulation is used, the insulation should be permeable 

enough to allow drying to the inside. Building Science Corporation 

(2009) recommends using up to two inches of unfaced extruded 

polystyrene (R-10), four inches of unfaced expanded polystyrene 

(R-15), three inches of closed-cell medium-density spray 

polyurethane foam (R-18), or up to ten inches of open-cell lowdensity spray foam (R-35) on the interior walls. The foam should be 

installed in a manner that forms an air barrier to prevent interior 

conditioned air from meeting the cold concrete basement wall, where 

condensation could form. The foam should be covered with a fire/

ignition barrier such as gypsum board per local building code. If a 

stud frame wall is used, additional insulation can be added to fill the 

stud cavities. Building Science Corporation notes that regardless of 

the insulation type used, a capillary break should be installed on the 

top of the footing between the footing and the perimeter foundation 

wall to control “rising damp” and a second capillary break should be 

installed between the foundation wall and framing.

For More Information on Basement Insulation 

BIRA, BSC, CARB, FSEC, IBACOS, and NREL. 2005. Building America Residential System 

Research Results: Achieving 30% Whole House Energy Savings Level in the Cold Climate. 

NREL/TP-550-38783, U.S. Department of Energy.

Broniek, John. 2003. Builder System Performance Packages Technical Report. Prepared by 

IBACOS for the Building America Program. Available at www.buildingamerica.gov in the 

publications section. 

Building Science Corporation. 2006. Read this Before You Design, Build or Renovate, 

Building Science Primer 040, www.buildingscience.com/documents/primers/

plonearticlemultipage.2006-12-05.5229931729/

Building Science Corporation. 2009. Basement Insulation, Info-511, May 14, 2009, 

www.buildingscience.com/documents/information-sheets/5-thermal-control/basement-insulation

DOE. 2009. Basement Insulation. U.S. Department of Energy, Energy Savers, 

www.energysavers.gov/your_home/insulation_airsealing/index.cfm/mytopic=11470

Lstiburek, Joseph. 2006. Builder’s Guide to Cold Climates. Building Science Press. Energy 

and Environmental Building Association.Westford, MA. 

Lstiburek, Joseph. 2011. Double Rubble Toil and Trouble, Insight 045, Feb. 2011, Building 

Science Corporation, www.buildingscience.com/documents/insights/bsi-045-doublerubble-toil-trouble/

Yost, Nathan, and Joseph Lstiburek. 2002. Basement Insulation Systems.

Prepared by Building Science Corporation for the Building America Program. 

www.eere.energy.gov/buildings/building_america/pdfs/db/35017.pdf 

8.11

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.11
Controlling Other Foundation Issues

Radon Control 

The EPA divides counties into one of three zones based on radonlevel potential. The EPA radon map on this page shows radon 

potential in the cold climate states by county. The EPA recommends 

that all homes built in zone 1 areas (high radon potential) have 

radon-reduction systems. The EPA cautions that local levels 

may vary and recommends that all homes be tested regardless of 

geographic location. Other than identifying areas that have had 

radon problems, it is not possible to predict radon levels in houses 

prior to construction, so it is important to include inexpensive 

radon-control measures when building new homes.

EPA Radon Zone Map 

(Source: www.epa.gov/radon/zonemap.html)

Zone 1 counties have a predicted average indoor radon 

screening level greater than 4 pCi/L (pico curies per liter)

Zone 2 counties have a predicted average indoor radon 

screening level between 2 and 4 pCi/L

Zone 3 counties have a predicted average indoor radon 

screening level less than 2 pCi/L

Highest Potential

Moderate Potential

Low Potential

Zone designation for Puerto Rico 

is under development.

The purpose of this map is to assist National, State, and local organizations to target their resources and to implement radon-resistant 

building codes. This map is not intended to be used to determine if a home in a given zone should be tested for radon. Homes with 

elevated levels of radon have been found in all three zones. All homes should be tested regardless of geographic location.

IMPORTANT: Consult the EPA Map of Radon Zones document (EPA-402-R-03-071) before using this map. This document contains 

information on radon potential variations within counties. EPA also recommends that this map be supplemented with available local data 

in order to further understand and predict the radon potential of a specific area.

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.12 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Measures taken to control foundation moisture are also important 

first steps in controlling radon. A layer of gravel (4-inch minimum) 

under the slab provides a path for radon and other soil gas to escape 

to the atmosphere rather than being drawn into the house. A sealed 

vapor retarder helps to block soil gas entry into the house. 

EPA’s “Model Standards and Techniques for Control of Radon in 

New Residential Buildings” discusses techniques for controlling 

radon with various foundation types. One measure recommended 

by the EPA to control radon and other soil gases is a passive soil 

gas stack that vents to the roof and is connected to a horizontal 

perforated drain pipe embedded in the gravel under the slab, 

basement floor, or crawlspace ground cover. The stack may also be 

attached to a strip of geotextile drainage matting. This system is 

often installed as a precaution even when no evidence of radon has 

been shown, because it is far easier to install during construction 

than to come back later and retrofit an under-slab venting system. 

The pipe can act as a passive vent. If it turns out the house has 

unacceptable radon levels, a fan can be added to the stack to actively 

draw soil gas away from the house. An electrical outlet should be 

installed in the attic for possible future fan installation. 

To determine potential radon levels in the county in which you are 

building, see the EPA radon potential map shown on the previous page 

and at www.epa.gov/radon/zonemap.html.

[Many of these radon control recommendations can be found in the

2009 IRC, Appendix F, which has recommended methods that are not 

required unless specifically referenced in the adopting ordinances.]

For More Information on Radon Control 

U.S. Environmental Protection Agency. Model Standards and Techniques for Control 

of Radon in New Residential Buildings. Cited 6/18/09. 

www.epa.gov/radon/pubs/newconst.html#Principles.

U.S. Environmental Protection Agency. 2009. EPA Map of Radon Zones, 

www.epa.gov/radon/zonemap.html

U.S. Environmental Protection Agency. 1995. Passive Radon Control System for New 

Construction, EPA 402-95-012. www.epa.gov/radon/rrnc/moreinfo.html

Landscaping

Landscaping is a critical element in the marketability of a house. 

Plants also can be used to shade foundations and reduce cooling 

loads. Choosing native plants results in the need for less irrigation 

and, thus, less chance for irrigation water to create a moisture 

problem in the house. 

8.13

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.13
Building America recommends plants be kept at least 18 inches from 

the finished structure, with any supporting irrigation directed away 

from the finished structure. Decorative ground cover, such as mulch 

or pea stone, should be no more than 2 inches deep for the first 18 

inches from the finished structure to assist drainage. 

Pest Control

The following pest control notes should be included on construction 

documents and details:

•	 Use local code and Termite Infestation Probability (TIP) maps to 

determine environmentally appropriate termite treatments, bait 

systems, and treated building materials for assemblies that are near 

soil or have ground contact. [The Termite Infestation Probability Map, 

Figure R301.2(6) in the 2009 IRC, shows slight to heavy probability of 

termite infestation across the cold climate.]

The 2009 IRC R318.1 dictates one or more of the following termite 

treatments: chemical termiticides; termite baiting; pressure/preservative 

treated wood; naturally termite-resistant wood; physical barriers, and 

steel framing.

In addition Building America recommends:

•	 Keep all wood (including siding, decking, and fencing that attaches 

to the house) from soil contact to minimize the presence of wet 

wood, which attracts carpenter ants.

•	 Use termite flashing and insulation products with termiticides or 

use fiberglass rigid insulation when insulating slab edge or exterior 

foundation walls.

Wall Assemblies

Controlling the intrusion of water and the movement of water 

vapor, air, and heat through the building envelope by proper design 

and construction of wall assemblies are major goals in the cold 

climate zone.

Controlling Liquid Water in Walls

Experience with buildings in most regions of North America has 

shown that drained and screened cladding systems are the preferred 

approach to reliably provide rain control. Drainage within the wall 

complements the shedding on the exterior surface.

(top) Place plants at least 18 inches from 

finished structure and direct irrigation 

away from the foundation.

(bottom) Carpenter ants are attracted to 

wet wood and can be very destructive. 

(Photo source: Michigan State University 

Extension)

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.14 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Builders must assume some rainwater will penetrate the outer surface 

of the wall. This water is removed or drained via a drainage screen 

within the wall. Some examples of drainage screened walls include stud 

cavity walls with lap siding, brick veneer, stone veneer, or vinyl siding. 

Walls in all climates should be constructed with flashing and drainage 

planes to direct water away from the structure and to the exterior. All 

drained enclosure systems must have a screen or cladding, a drainage 

gap ( a clear air space), a drainage plane (a water-repellent plane), 

flashing at the base to direct water outwards, and drain holes (weep 

holes) to allow water out of the drainage gap. Although drainagescreened walls provide excellent rain penetration control, problems 

can still develop at interruptions in the plane of the wall. 

Care should be taken to overlap all wall layers to provide an exit 

pathway for all precipitation down and out of the building assembly 

as follows:

•	 Lap all materials in shingle fashion to direct water down and out, 

away from the wall assembly. 

•	 Flash all wall penetrations and interruptions (windows, decks, and 

the termination of walls at grade).

•	 Incorporate extended overhangs in the design to keep water away 

from walls and windows and to provide shade. Sizing of overhangs 

for shade is described in Chapter 5.

•	 Install gutters.

•	 Back prime and back vent siding.

•	 Use housewrap.

•	 Elevate the bottom of the wall enough to prevent rain from 

splashing up on the siding.

Drainage Planes

Elevation drawings should specify building paper, housewrap, or 

taped insulating sheathing (rigid foam insulation) behind the exterior 

cladding to serve as a drainage plane or water-resistive barrier [2009 

IRC R703.2] (also called a house membrane or rain barrier). This 

drainage plane can sometimes also serve as the exterior air barrier. 

None of these materials is waterproof, but they will shed rainwater 

that penetrates exterior cladding. They can prevent liquid water 

from wicking through, while remaining sufficiently vapor permeable 

(“breathable”) for outward drying (Straube 2001). 

Drainage Plane Choices 

(House Membrane or Rain Barrier)

None of these is waterproof but 

they serve to shed rainwater that 

penetrates exterior cladding while 

remaining vapor permeable.

(Adapted from Straube 2001)

Building Paper is a kraft paper sheet 

impregnated with asphalt to increase 

its strength and resistance to water 

penetration. It is primarily employed as a 

drainage layer. It is graded according to a 

test of the amount of time required for a 

water-sensitive chemical to change color 

when a boat-shaped sample is floated on 

water. Common grades include 10, 20, 30, 

and 60 minutes. The larger the number, 

the more resistant the paper is to water.

Building Felts have been in use for 

over 100 years. Originally made from 

rags, today’s felts are made of recycled 

paper products and sawdust. The base 

felt is impregnated with asphalt. Ratings 

for felt harken back to the traditional 

weight of the material before the oil crisis 

of the 1970s. At that time 100 square 

feet of the material (1 square) weighed 

about 15 pounds. Modern #15 felt can 

weigh from 7.5 to 12.5 pounds per square 

depending on the manufacturer.

Housewrap typically refers to specially 

designed plastic sheet materials. 

Housewrap comes in a variety of 

materials and can be perforated or 

non-perforated. If joints and connections 

are sealed, housewraps can serve as 

air retarders to reduce air leakage. 

Housewraps are highly resistant to 

tearing, unlike building paper. Nonperforated wraps tend to have higher 

liquid water resistance because the holes 

between plastic fibers are very small.

8.15

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.15
Most building paper is UV-resistant, whereas housewrap UV-exposure 

limits vary. If building paper is used as a drainage plane in areas prone 

to severe storms, use two layers to increase resistance to leakage 

at fasteners and allow for more flexible installation. If felt is used, 

install it half-lapped to create two layers.

Installation is key for all types of housewraps. See the Installers Guide on 

installing housewraps in Chapter 14. During construction and operation, 

it is important that housewraps remain clean. Surface contaminants 

interfere with the wrap’s ability to hold out water. Some cladding 

can contaminate wraps if the two are in direct contact. For example, 

water-soluble extractives in wood, such as tannins and wood sugars 

in redwood and cedar, can contaminate the surface of housewraps 

and building papers. Back-priming or back-coating wood clapboards 

and trim helps to isolate the surfactants in the wood from the housewrap 

or building paper surface. Back priming is also recommended on all 

wood and cementitious cladding systems to avoid water saturation, 

migration, and potential warping and rot. Stucco should never be 

installed in direct contact with any of the plastic-based housewraps. 

Installation is key for all types of housewraps. See the Installers 

Guide on installing housewraps in Chapter 14. During construction 

and operation, it is important that housewraps remain clean. 

Surface contaminants interfere with the wrap’s ability to hold out 

water. Some cladding can contaminate wraps if the two are in direct 

contact. For example, water-soluble extractives in wood, such as 

tannins and wood sugars in redwood and cedar, can contaminate the 

surface of housewraps and building papers. Back-priming or backcoating wood clapboards and trim helps to isolate the surfactants 

in the wood from the housewrap or building paper surface. Back 

priming is also recommended on all wood and cementitious cladding 

systems to avoid water saturation, migration, and potential warping. 

Provide a drainage space to prevent wetting of the housewap or use 

two layers of textured building paper. Apply shingle fashion and 

install a weep screed at the bottom of the wall sheathing beneath the 

first layer of housewrap (Lstiburek 2008).

Drainage Gaps

It is essential to provide an air gap or air space between cladding and 

housewraps to reduce the time liquid phase water is trapped in the 

exterior of the wall assembly. A drainage gap between wood or fiber 

cement cladding and housewraps can be provided by 1x4 furring 

strips (“cedar-breather”), contoured housewrap, or some other spacer. 

Building America recommends a gap of at least 1/6-inch behind lap 

siding and a drainage space of 3⁄4 inch between stucco and plastic 

housewraps to control liquid phase water penetration. A 1-inch air 

gap is needed behind brick veneer [as required by 2009 IRC R703.7.4.2].

Taped rigid foam insulation can serve as 

a drainage plane, air barrier, and vapor 

barrier as well as a thermal boundary 

behind a stucco cladding. If using 

housewrap instead, never apply stucco 

directly to plastic housewrap. Provide a 

drainage space to prevent wetting of the 

housewap or use two layers of textured 

building paper.

(top) This pipe is flashed with flexible 

flashing. Housewrap is layered shingle 

style over the top edge of the flashing. 

(bottom) New Tradition Homes of 

Washington State flashes the bottom 

edge of its wall sheathing, then layers 

housewrap over the top edge of the 

flashing, as shown in this display.

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.16 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Flashing 

Details should be provided for flashing for all windows and doors; 

wall-roof junctions; attachments (such as porches and decks); 

projections and offsets (such as bay windows); and pipes, vents, 

wiring, exterior light fixtures, and other penetrations through the 

wall. See Chapter 14 for instructions on installing window flashing. 

[Flashing should be specified in accordance with the 2009 IRC R703.8.] 

Additional guidance can be found in the EEBA Water Management 

Guide (Lstiburek 2006a) and DOE’s Technology Fact Sheet on 

Weather-Resistive Barriers (DOE 2000), available on the Web at 

www.eere.energy.gov/buildings/info/documents/pdfs/28600.pdf.

Drain all water away from the structure

Controlling Water Vapor in Walls

As discussed in Chapter 6, most vapor transmission through 

building assemblies is via air flow so stopping air leaks is an 

important way to prevent water vapor from getting into walls. Water 

vapor can also move via diffusion. Vapor pressure moves water 

vapor from indoors to outdoors during cold-dry weather and from 

outdoors to indoors during hot-humid weather. Water vapor that is 

trapped in walls or condenses in walls due to temperature differences 

can cause moisture problems like mold. Vapor retarders will stop 

this vapor diffusion.

Drain Wall

Drain Roof

Drain Building

Drain Site

Drain Ground Drain Ground

Drain Site

Drain Materials

Drain Components

Drain Openings

➊ Brick veneer/stone veneer/

ship-lapped siding

➋ Drainage cavity

➌ Exterior rigid insulation – extruded 

polystyrene, expanded polystyrene, 

rigid fiberglass

➍ Housewrap

➎ Non-paper-faced exterior gypsum 

sheathing, plywood, or oriented strand 

board (OSB)

➏ Insulated wood stud cavity

➐ Gypsum board

➑ Latex paint or vapor semi-permeable 

textured wall finish. No vapor barrier 

on inside (no polyethelene sheeting, 

no vinyl wallpaper on exterior walls)

VAPOR PROFILE

➊ ➋➌➍ ➎ ➏ ➐ ➑

Vapor Retarder Recommendations: 

•	 Allow building assemblies to dry to

either the exterior or the interior or both.

•	 Avoid use of a less permeable vapor

retarder where a more permeable 

retarder will provide satisfactory 

performance, to encourage drying.

•	 Avoid installing vapor barriers on both

sides of assemblies, i.e., double vapor 

barriers, to facilitate assembly drying in 

at least one direction.

•	 Avoid installing Class I vapor barriers

(polyethylene sheet, foil-faced batt) on 

the interior of air conditioned assemblies.

•	 Avoid vinyl wall coverings on the inside

of air conditioned assemblies.

•	 Ventilate to ASHRAE 62.2.

(Source: Lstiburek 2006c) 

8.17

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.17
Vapor Retarders

[According to the 2009 IRC R601.3], in the cold climate Class 1 or 2 

vapor retarders are required (except as described in the following 

paragraphs) on the interior side of unvented, framed walls, 

except for basement walls, the below-grade portion of any wall, 

or construction where moisture or its freezing will not damage 

the materials. Examples of Class 1 vapor retarders include sheet 

polyethylene and unperforated aluminum foil. An example of a 

Class 2 vapor retarder is kraft-faced fiberglass batt insulation. 

[According to the 2009 IRC R601.3], in the cold climate (IRC/IECC 

climate zones 5, 6, and 7), Class 3 vapor retarders (e.g., latex paint) 

can be used instead of Class 1 or Class 2 vapor retarders when walls 

are vented as described in the table in Chapter 6.

Vapor retarders can block the entry of vapor. However, vapor 

retarders can also block vapor’s exit. It is important that moisture 

not get trapped inside of walls. Walls need to dry to the interior, 

the exterior, or both. To avoid trapping moisture in walls, Building 

America recommends that Class 1 or 2 vapor retarders not be placed 

on the interior side of the building envelope between gypsum board 

and framing; Class 3 vapor retarders, such as latex paint, should be 

used instead. Vinyl-coated wallpaper is not recommended on the 

walls or ceilings that form the building envelope of homes in the cold 

climate. 

Use of rigid foam exterior sheathing reduces the need for a Class I 

or II interior vapor retarder. This insulated sheathing reduces the 

probability of condensation inside the wall. In hot, humid weather, 

insulating sheathing acts as a vapor retarder and helps prevent 

moist outdoor air from entering the wall, reducing the potential for 

condensation to form on the back side of the interior gypsum board 

of air-conditioned homes. In cold weather, the exterior foam layer 

minimizes thermal bridging from the studs to the outside and keeps 

the wall cavity temperature above dew point, reducing the likelihood 

of condensation forming on the interior surface of the sheeting. If 

the foam is taped at the seams and caulked at the edges, it serves as 

an air barrier and rain screen.

Drainage Spaces

Cladding should have a drainage space behind it of 1 or 2 inches for 

brick and stone veneer, 3/4 inch for stucco, and 1/16 inch for siding. 

Bricks and other masonry absorb water in the form of precipitation 

and irrigation. Solar energy will then drive this moisture in the 

form of vapor into the wall assembly. The 1-inch gap [as required 

by 2009 IRC R703.7.4.2] allows the vapor to dissipate before entering 

Windows

One critical point of concern is water 

leakage around windows. The EEBA Water 

Management Guide (Lstiburek 2006) 

offers examples of many window flashing 

applications. See Chapter 14 for detailed 

examples of window flashing for homes 

with housewrap and plywood or OSB 

sheathing. Window and door flashing 

details should be designed to match 

specific wall assemblies and claddings. 

Flashing systems should be designed in 

accordance with ASTM Standard E2112-

07, “Standard Practice for Installation of 

Exterior Windows, Doors, and Skylights” 

(ASTM 2007).

Water should not be directed to flow into 

the wall. This could soon lead to water 

intrusion in the wall.

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.18 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
wall cavities. An air space stops capillary movement of moisture, 

discourages vapor diffusion, stops the contamination of the drainage 

plane via contact with the cladding, and allows air circulation for 

better drying. In some wall assemblies, ventilation openings to the 

exterior at both the top and bottom further encourage drying. See 

Straube (2009) for information about the performance of drainage 

spaces with different wall types.

Dry Building Materials

Building with wet or green materials can be a source of vapor in 

walls. Damp lumber should be allowed to dry before use to 12% 

moisture content (FPL 2010) or as required by local code; heaters 

may be required for adequate drying in cold weather. Interior 

relative humidity should be kept to less than 35% during the coldest 

part of the heating season.

Air Sealing

Water vapor is far more likely to be transported into walls by air 

movement than by diffusion. Therefore, air sealing is an important 

method for preventing water vapor movement into walls. Air sealing is 

further described in the next section. 

Controlling Air Infiltration in Wall Assemblies

[The 2009 IECC 402.4 requires that the building thermal envelope be 

durably sealed to limit infiltration and specifies that the following areas 

should be caulked, gasketed, weather-stripped or otherwise air sealed: all 

joints, seams, and penetrations; site-built windows, doors, and skylights; 

window and door openings; utility penetrations; dropped ceilings or 

chases on exterior walls; knee walls; walls and ceilings separating a 

garage from the conditioned space; behind tubs and showers on exterior 

walls; common walls between dwelling units; attic access openings; rim 

joist junctions; and other sources of infiltration. Air leakage is to be tested 

with a blower door or visual inspection.] To be effective the air barrier 

must be continuous, meaning that it extends over the entire envelope 

of the structure, although it may be made up of many materials. 

Indicate on plans the methods, materials, and locations where sealing 

is needed to form the house air-pressure barrier.

(top) When rigid foam insulation is applied 

to the exterior side of the wall cavity under 

the cladding, with seams taped and glued 

down, it acts as a vapor barrier, preventing 

moisture in brick and stucco finishes from 

being driven inward during drying. It also 

serves as an air barrier and rain screen, and 

during the heating season, it maintains the 

temperature of the wall cavity above dew 

point, to prevent condensation. (Photo 

Source: S+A Homes)

(bottom) Window flashing on outside 

is overlapped to provide a continuous 

drainage plane.

8.19

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.19
Tape

Housewrap Caulk

Sil gasket

Gypsum

board

Structural

sheathing

Tape and joint

compound seal

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed to bottom plate

Drywall caulked or glued 

to top plate

Ceiling drywall taped

to wall drywall

Use rigid foam 

or sheet goods to 

seal joist cavities

Seal

Adhesive, Gasket or Caukling

Drywall

Hardboard,

rigid foam,

or sheet goods

Seal

HOUSEWRAP

HOUS

OUSEWRAP

HOUSEWRAP

Before installing 

the window, caulk 

the outside edges 

of the head and 

side jambs

Do not caulk

across the sill

CAULK

CAULK

Seal gap between 

window and rough

opening on interior

Recessed light fixtures 

should be rated for 

Insulated Ceiling Air 

Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight wire

connection from 

junction jox

Airtight

can

Decorative

cover Caulk

or gasket

Seal

Support sheathing

Electrical

panel

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to

drywall air barrier

Select boxes with 

built-in gasket

and sealant

Seal

Solid air barrier

material sealed at

perimeter and seams

CAULK

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimeter

Insulation in permanent

contact with subfloor

Tape

Rim joist Rigid or blown-in

foam insulation

Housewrap

Sill gasket

CAULK

Tape

Housewrap Caulk

Sil gasket

Gypsum

board

Structural

sheathing

Tape and joint

compound seal

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed to bottom plate

Drywall caulked or glued 

to top plate

Ceiling drywall taped

to wall drywall

Use rigid foam 

or sheet goods to 

seal joist cavities

Seal

Adhesive, Gasket or Caukling

Drywall

Hardboard,

rigid foam,

or sheet goods

Seal

HOUSEWRAP

HOUS

OUSEWRAP

HOUSEWRAP

Before installing 

the window, caulk 

the outside edges 

of the head and 

side jambs

Do not caulk

across the sill

CAULK

CAULK

Seal gap between 

window and rough

opening on interior

Recessed light fixtures 

should be rated for 

Insulated Ceiling Air 

Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight wire

connection from 

junction jox

Airtight

can

Decorative

cover Caulk

or gasket

Seal

Support sheathing

Electrical

panel

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to

drywall air barrier

Select boxes with 

built-in gasket

and sealant

Seal

Solid air barrier

material sealed at

perimeter and seams

CAULK

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimeter

Insulation in permanent

contact with subfloor

Tape

Rim joist Rigid or blown-in

foam insulation

Housewrap

Sill gasket

CAULK

Kneewalls: The taped, mudded drywall 

forms an air seal for the attic room but 

floor joist openings below the attic room 

floor can be a big source of air leakage. 

Stop this air leakage by one of the 

following: A) Block the floor joist openings 

with sheet goods (drywall, rigid foam, 

OSB) that is cut to fit each opening or 

pieces of batt insulation that are rolled and 

put in plastic bags that are stuffed into the 

openings. Seal around the edges of either 

with spray foam or caulk to form an airtight seal; or B) Continue insulation along 

roof line to roof edge, cover with sheet 

good that is caulked where it meets wood 

floor sheathing that is extended to outside 

wall. This method forms a tempered area 

with flooring for storage as well.

Exterior Air Barrier with Rigid Foam Sheathing – 

Points to Seal

(see house figures at right) Air sealing is Interior Air Barrier – Points to Seal

needed throughout the house to ensure 

an airtight shell. The house on top uses 

conventional approaches. The house on the 

bottom uses external rigid foam sheathing, 

which provides a continuous air barrier so 

fewer air sealing steps are required. Foam 

sheathing can also serve as a drainage 

plane, vapor barrier, and thermal barrier. 

(Detailed drawings are in Chapter 14.)

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.20 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
A comprehensive air-sealing strategy begins with indicating on the 

house plans the location of the conditioned space by outlining the 

building envelope. The plans should show the location of complex 

details like chases, stairwells, dropped ceilings, fireplace penetrations, 

balconies, and knee walls, so that they can easily be identified as 

being inside or outside the conditioned space. The plans also should 

show where insulation and draft stopping should be installed. 

If the air barrier will be on the interior side of the walls, it is 

important to specify that all drywall joints be caulked, mudded, and 

taped. To ensure an airtight envelope when the air barrier is on the 

inside of the building envelope, builders should address the following 

common sources of air leakage through walls:

•	 Insulate and air seal behind tubs and shower stalls on the exterior 

walls by filling the wall cavity with insulation, and then installing 

and sealing rigid sheathing material on the interior surfaces of the 

wall before the tub or shower is installed. 

•	 Line fireplace enclosure framing with rigid sheathing material, 

like gypsum board, plywood, wafer board, or foil-covered pressed 

paper, and seal edges to box in sides, top, and bottom of fireplace 

enclosure. Wood-burning fireplaces should have gasketed doors 

and outdoor combustion air [per 2009 IECC 402.4.3].

•	 Air seal chimney chases and around the chimney flue where it 

penetrates the ceiling using sheetmetal and heat-resistant caulk.

•	 Box in tops and ends of soffits and dropped ceilings with sheathing 

that is caulked to framing on all edges.

•	 Fill in the rough opening around windows and doors with foam, 

caulk, or backer rod.

•	 Apply housewrap and flashing as shown in Chapter 14.

•	 Caulk, foam, or seal with gaskets all penetrations for electrical 

boxes, outlets, switches, and plumbing.

Alternatively, the air barrier can be placed on the outside of the 

building envelope. One method for doing this is to install rigid 

foam on the exterior side of the wall under the cladding. This foam 

sheathing can provide a continuous air barrier when all seams are 

taped and caulked. This exterior air-barrier system can also help 

control wind washing. 

Cladding should have a drainage 

space behind it of 

• 1 inch for brick [2009 IRC R703.7.4.2]

• 3/4 inch for stucco, and

• 1/16 inch for siding.

8.21

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.21
For occupant health and safety, builders should pay close attention 

to sealing shared walls and ceilings between attached garages and 

living spaces. When the garage is attached to the house, the gaps 

created by joists spanning both conditioned space and the garage 

must be blocked off and sealed. Creating air barriers to close gaps 

between the garage and the conditioned space is more difficult with 

irregularly shaped joists, such as I-joists and web-trusses. A simple 

solution is to plan ahead and align the ends of the joists with the 

wall adjoining the conditioned space to allow for end blocking.

Envelope Air Sealing

(Figure source: Building Science Corporation)

Gaps between garage and conditioned 

space are properly sealed by carefully 

cutting and then caulking wood sections 

to fit between trusses. (Photo Source: EPA 

2008 “Thermal Bypass Checklist”)

Tape

Housewrap Caulk

Sil gasket

Gypsum

board

Structural

sheathing

Tape and joint

compound seal

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed to bottom plate

Drywall caulked, glued 

or gasketed to top plate

Ceiling drywall taped

to wall drywall

Use rigid foam 

or sheet goods to 

seal joist cavities

Seal

Hardboard

Seal

HOUSEWRAP

HOUSEWRAP

HOUSEWRAP

HOUSEWRAP

Before installing 

the window, caulk 

the outside edges 

of the head and 

side jambs

Do not caulk

across the sill

CAULK

CAULK

Seal gap between 

window and rough

opening on interior

Recessed light fixtures 

should be rated for 

Insulated Ceiling Air 

Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight wire 

connection from 

junction jox

Airtight

can

Decorative

cover Caulk

or Gasket

Sealant

Support sheathing

Electrical

panel

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to 

drywall air barrier

Select boxes with 

built-in gasket 

and sealant

Seal

Solid air barrier

material sealed at 

parimeter and seams

CAULK

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimenter

Insulation in permanent

contact with subfloor

Air seal gasket

Rigid insulation

REGISTER

Seal boots to 

sheet goods with 

caulk, mastic, or 

spray foam

Tape

Rim joist Rigid or blown-in

foam insualtion

Housewrap

Sill gasket

CAULK

Wood or rigid foam filler blocking is 

cut to fit the gaps between floor joists 

and caulked or foamed in place to form 

an air break between conditioned and 

unconditioned spaces.

Attic access panel air sealing

Garage common wall air sealing

with 

 

Seal

Solid air barrier

material sealed at 

parimeter and seams

CAULK

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimenter

Insulation in permanent

contact with subfloor

Air seal gasket

Crawlspace

Rigid insulation

REGISTER

Seal all joints in 

boot and elbow

with mastic

Seal boots to 

sheet goods with 

caulk, mastic, or 

spray foam

 

 

od

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed; inside seam 

taped and mudded

GARAGE

Bottom plate caulked

or gasketed to subfloor

 on interior, exterior,

or both surfaces

Drywall caulked, 

glued or gasketed 

to top plate on interior, 

exterior, or both surfaces 

CAVITY

Solid air barrier

material sealed

at perimeter

CAULK

Use caulk or adhesive to

seal panels to joists at seams

INTERIOR - 

Using gypsum and flooring

EXTERIOR - 

Using rigid foam sheathing

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.22 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Controlling Heat Flow in Wall Assemblies

The control of heat flow in the building is managed by the type, 

thickness, location, and proper installation of insulation. [The 2009 

IECC 402 requires a wall R value of R-20 for wood-framed walls (or R-13 

cavity plus R-5 insulated sheathing) for IECC climate zones 5 and 6 and 

R-21 for IECC climate zones 7 and 8. For mass walls (concrete block, 

concrete, ICF, brick, etc.), the requirement is R-13 for exterior insulation or 

R-17 if more than half the insulation is on the interior in zone 5, R-15/19 for 

IECC climate zone 6, and R-19/21 for IECC climate zones 7 and 8.]

Window selection and design are also important. 

Consider implementing the following above-code recommendations: 

• Use advanced framing techniques to cut lumber costs and 

provide more space for insulation. Provide advanced framing 

details on plans.

• Specify that cavity walls separating conditioned and unconditioned 

spaces be insulated with high-density batt insulation, dense-packed 

fibrous insulation, or spray-applied foam.

• Specify that spray foam be used to insulate and seal rim joists at 

areas between floors or where the wall connects to the floor.

• Specify that taped rigid foam insulating sheathing be used on 

the exterior side of studs in addition to cavity insulation. This 

sheathing eliminates thermal bridging at the studs.

• Use third-party inspectors or HERS raters to inspect insulation 

installation before dry walling.

• Specify ENERGY STAR-labeled doors.

• Design roofs and overhangs to shade and protect windows, doors, 

and walls.

Masonry walls may be finished with stucco, wood, or other claddings. 

Best practices to improve thermal efficiency include the following: 

• Semi-vapor permeable rigid insulation should be installed on the 

interior of wall assemblies and should be unfaced. Foil facing and 

polypropylene skins should be avoided.

• Wood furring should be installed over rigid insulation. The rigid 

insulation should be continuous over the surface of the wall, 

except for a 2x4 furring at the intersection with the ceiling. This 

blocking attaches directly to the masonry block and serves as a 

draft and fire stop. The rigid insulation abuts the blocking but does 

not cover it or extend behind it. Foam seal or caulk all top plate 

penetrations and exterior wall penetrations. 

Code/Above Code 

Wall Insulation Above Grade

A comparison of the 2009 IECC climate 

zones 5–8, and Building America 

recommendations

Code

2009 IECC Wood 

Framed

Mass 

Wall***

IECC 5 R-20 or 

13+5* R-13/17

IECC 6 R-20 or 

13+5* R-15/19

IECC 7 R-21 R-19/21

Above Code

Building America 

Recommendations

1 to 2 inches rigid foam 

exterior insulation, taped 

at seams,** plus 

R-21 fiberglass batt, 

or R-19 blown fiberglass

or blown cellulose

* R-13 cavity insulation + R-5 rigid foam sheathing

** Insulate the headers with R-10 (2 inches) of 

rigid foam board

***The second R-value applies when more 

than half the insulation is on the interior of the 

mass wall.

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Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.23
• Use pressure-treated lumber to frame out sub-jambs and 

spacers within window and door rough openings.

• As with other walls, penetrations to the exterior or through top 

and bottom plates should be foam sealed or caulked. Also air seal 

penetrations to garages and porches.

• Mud, tape, and caulk seams and corners of gypsum board to 

control air leakage through the walls.

• When pouring the slab, take care to create a seat in the concrete 

to accept the block and seats in the concrete to act as drain pans 

where exterior doors and sliding doors will be located. 

Roof Assemblies

Controlling Liquid Water in Roof Assemblies

Roof and wall assemblies must contain surfaces that will drain 

water in a continuous manner down and off the building. Water 

must have a path that will take it from its point of impact, around 

any elements, such as chimneys, windows, doors, and seams, all 

the way to the exterior ground, and away from the house. Consider 

implementing the following recommendations: 

•	 Properly flash valleys and roof edges.

•	 Size gutters and downspouts to accommodate anticipated 

storms. Show gutter sizes on elevations and specify sizes in 

construction documents.

•	 Provide downspout drainage to carry water at least 3 feet 

beyond the building.

•	 In areas with potentially high winds and heavy rains, install 

4-inch to 6-inch “peel and seal” self-adhering water-proofing 

strips over joints in roof decking before installing the roof 

underlayment and cover.

•	 Keep roof geometry simple. The more complex the roof—the more 

dormers, ridges, and valleys—the more likely the roof will leak. 

Ice Dam Protection 

Ice dams can form when the air temperature is below freezing, but the 

roof deck temperature is above freezing, causing snow on the roof to 

melt. The melted snow flows to the edge of the roof where it refreezes, 

forming an ice dam that collects more water. The dam may not be 

(top ) RDI used a basic roof shape on 

its homes in Greenfield, Massachusetts, 

which minimizes the need for complicated 

flashing and provides the added benefit 

of more space for photovoltaics and solar 

water heating panels (Photo Source: RDI).

(bottom) Kick-out flashing should be 

installed to divert water runoff into gutters 

rather than flowing down the wall.

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.24 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Ice dams can form when the roof deck 

temperature is above freezing and the air 

is below freezing. Snow melts, runs down 

to the edge of the roof and refreezes 

forming a dam that traps more water and 

ice. Air leaks in ceilings and insufficient 

attic insulation allow heat to rise into attic 

warming roof deck and encouraging ice 

dam formation.

Three Steps to Ice Dam Control – 1) 

Construct an airtight ceiling plane. Limit 

the number of holes through the ceiling 

and air seal every one. 2) Insulate well, 

especially over the top plates, use raised 

heel trusses if needed to get full insulation 

coverage. 3) Vent the underside of the roof 

deck, with vent screens at every rafter bay 

and a 2-inch airspace under the sheathing 

where ground snow loads are greater than 

30 lb/ft2. For more guidance, including 

how to prevent ice dams on an unvented 

roof, see the Ice dam prevention field 

guide in Chapter 14 (Source Lstiburek 2011, 

Building Science Corporation)

visible under the snow but large amounts of icicle formation are a 

telltale sign. The water built up behind an ice dam can work its way 

into the house causing damage to building assemblies; other serious 

consequences are falling ice and structural collapse from the weight 

of ice and water buildup. While protective membranes and heating 

systems may treat the symptoms, the best solution is to keep ice dams 

from occurring in the first place. In a recent paper Joseph Lstiburek 

of Building America team partner Building Science Corporation, 

describes several approaches to ice dam prevention (Lstiburek 2011). 

The control approach involves keeping heat from the home’s interior 

from reaching the roof deck by thoroughly air sealing the ceiling lid, 

covering it with a thick layer of insulation, and removing any heat 

that reaches the roof deck via ventilation of the roof deck. Lstiburek 

recommends going beyond code to ventilate every truss bay, not every 

third bay and providing a minimum 2-inch air gap (not the typical 

code-required 1-inch gap) between the underside of the roof deck 

and the top layer of insulation in the attic in ice dam-prone regions 

(where ground snow load exceeds 30 lb/ft2). Minimize the number of 

holes through the ceiling (recessed can light fixtures, dropped soffits, 

etc.) because every air leak carries heat right up to the underside of 

the roof where it can warm the roof deck, creating ice dam conditions. 

Furnaces and ducts should not be located over the insulation in an 

unconditioned attic in the cold climate because of the likelihood of 

warm air leaks from the ducts and furnace. 

A furnace could be located in the attic if the insulation is above the 

furnace along an unvented roof deck, e.g., if the underside of the 

roof deck is insulated with spray foam or if rigid foam insulation 

is placed over a roof sheathing that is covered with a continuous 

air barrier membrane. In areas with a lot of snow (ground snow 

load of >50 lb/ft2), the snow itself can add enough insulation value 

to the insulated roof deck that the roof deck temperature could 

exceed freezing even when the air temperature is below freezing. To 

prevent ice dam formation in this situation, Lstiburek recommends 

constructing a vented over roof over the unvented compact roof 

(See Chapter 14, Field Guide for Ice Dam Prevention).

•	 Use raised heel trusses if needed to ensure adequate insulation 

directly at edges of attics directly over wall top plates and caulk to 

air seal top plate to dry wall and wall exterior sheathing. 

•	 Minimize penetrations through ceiling lid and thoroughly air seal 

around any penetrations – especially wall intersections, recessed 

lights, soffits, duct chases, etc. 

•	 Vent bath and kitchen exhaust fans out of the attic with sufficient 

clearance to keep warm air from warming roof. 

8.25

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Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.25
•	 Install adequate insulation across the roof and ensure proper 

insulation levels above exterior walls by using raised-heel roof trusses. 

•	 Apply a water-protection membrane at the eaves in case of 

ice dam formation. 

[Per 2009 IECC 403.8 snow- and ice-melting systems, supplied through 

energy service to the building, shall include automatic controls capable 

of shutting off the system when the pavement temperature is above 

50°F, and no precipitation is falling and an automatic or manual control 

that will allow shutoff when the outdoor temperature is above 40°F.]

Controlling Water Vapor in Roof Assemblies

Vapor retarder requirements for roofs are defined in Lstiburek 

(2006C) as follows: “Zone 5 requires a Class III (or lower) vapor 

retarder on the interior surface of insulation in ventilated insulated 

roof or attic assemblies. Zone 5, Zone 6 and Zone 7 require a Class 

II (or lower) vapor retarder on the interior surface of insulation 

in unvented insulated roof or attic assemblies and the condensing 

surface shall be maintained above the dew point temperature of the 

interior air. The condensing surface is defined as either the interior 

surface of the structural roof deck or the interior surface of an airimpermeable insulation applied in direct contact to the underside/

interior of the structural roof deck.” 

Controlling Air Flow in Roof/Attic Assemblies

Air sealing of the ceiling uses techniques similar to those used for the 

walls including mudding and taping of dry wall seams and caulking 

of cracks. [The 2009 IECC 402.4 requires that the building thermal 

envelope be air sealed, including all joints, seams, and penetrations; 

dropped ceilings; knee walls; walls and ceilings separating a garage from 

conditioned space; attic access openings; rim joist junctions; and other 

sources of infiltration.]

Air sealing details to consider include:

•	 Provide details on plans for air sealing and insulating complex 

structures like kneewalls, gable windows, porch-attic interfaces, 

and cathedral ceilings. 

•	 Seal all penetrations and seams in ceiling gypsum board so that it 

functions as a continuous air barrier. 

•	 Draft-stop soffits with rigid air barrier caulked at seams. 

•	 Gasket or weather strip attic access hatches or doors and insulate 

to ceiling insulation depth [as required by 2009 IECC 402.2.3]. 

Baffles allow ventilation under roof decking 

while keeping wind from blowing insulation 

back from the edges of an attic.

Code/Above Code 

Ceiling Insulation

A comparison of the 2009 IECC climate 

zones 5–8, and Building America 

recommendations

Code

2009 IECC

IECC 5 R-38*

IECC 6 R-49**

IECC 7&8 R-49*/***

Above Code

Building America 

Recommendations****

R-49 blown 

fiberglass or blown 

cellulose

R-49 spray foam on 

ceiling deck

R-49 spray foam 

along underside of 

roof deck

R-49 rigid foam 

exterior insulation 

on top of roof 

sheathing*

* R-30 if cathedral but cathedral must be 

limited to 500 ft2 or 20% of total insulated 

ceiling area, whichever is less. 

**R-30 permitted if raised heel trusses used. 

*** R-38 permitted if raised heel trusses used. 

**** Level recommended by NWPCC 2010. 

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.26 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
•	 Install recessed lighting fixtures that are airtight and caulk or 

gasket the housing to the ceiling drywall [per 2009 IECC 402.4.5].

•	 Provide a weather-stripped cover for whole-house fans.

•	 Ensure that skylights have a labeled infiltration rate of no more 

than 0.3 cfm/ft2 [per 2009 IECC 402.4.4].

Controlling Heat Flow in Roof Assemblies

Maintaining the insulation level throughout the entire plane of the 

ceiling and over the top of the perimeter walls is key to controlling 

heat flow through the attic. Raised-heel energy trusses allow the 

thickness of the ceiling insulation to be maintained above the top 

plates of the exterior wall framing. Baffles should be installed at 

each rafter bay to prevent wind washing of thermal insulation 

and to prevent insulation from blocking ventilation in vented roof 

assemblies. [The 2009 IECC 402.1 requires a ceiling R value of R-38 in 

IECC climate zone 5 and R-49 in IECC zones 6, 7, and 8. If raised heel 

trusses are used allowing full height of insulation over the wall top 

plate, then R-30 is permitted instead of R-38 in IECC zone 5 and R-38 

is permitted instead of R-49 in zones 6, 7, and 8. A minimum of R-30 is 

required in cathedral ceilings, but this is limited to 500 ft2 or 20% of 

total insulated ceiling area, whichever is less (2009 IECC 402.2.2.)]

For More Information on Moisture, Air, 

and Heat Flow Control in Walls and Roofs

2009 IECC. 2009. International Energy Conservation Code, Section 402.4 “Air Leakage,” 

International Code Council (ICC), Washington, D.C. www.iccsafe.org/Store/Pages

2009 IRC. 2009. International Residential Code - One and Two-Family Dwellings, 

International Code Council (ICC), Washington, D.C. www.iccsafe.org/Store/Pages

ASTM. 2007. Standard Practice for Installation of Exterior Windows, Doors, and Skylights. 

www.astm.org/Standards/E2112.htm

Buildernews Magazine, May 2004, “Housewrap Felt or Paper: Comparing specs on weather barriers”

Building Science Corporation. Homeowner Information Resources.

www.buildingscienceconsulting.com/resources/homeowner.htm

Building Science Corporation. 2006. Info-500: Building Materials Property Table, Building Science 

Corporation, April 16, 2010, www.buildingscience.com/documents/information-sheets/5-

thermal-control/building-materials-property-table

DOE. “Vapor Barriers and Vapor Diffusion Retarders.” Energy Savers Fact Sheet, 

www.energysavers.gov/your_home/insulation_airsealing/index.efm/mytopic=11810

DOE. 2000. Technology Fact Sheet on Weather-Resistive Barriers. Prepared by NAHB 

Research Center, Southface Energy Institute, and Oak Ridge National Laboratory for the 

U.S. Department of Energy, DOE/GO10099-769, www.toolbase.org/PDF/DesignGuides/

weatherresistantbarriers.pdf

DOE. 2009. Moisture Control in Walls, Energy Savers, 

www.energysavers.gov/your_home/insulation_airsealing/index.cfm/mytopic=11800?print

ENERGY STAR. 2008. Thermal Bypass Checklist Guide www.energystar.gov/ia/partners/

bldrs_lenders_raters/downloads/TBC_Guide_062507.pdf, pg. 13

8.27

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.27
Forest Products Laboratory. 2010. Wood Handbook, FPL-GTR-190, Forest Products 

Laboratory, U.S. Department of Agriculture, www.fpl.fs.fed.us/products/publications/

several_pubs.php?grouping_id=100&header_id=p

Gatland, S. D., Karagiozis, A. N., Murray, C., and Ueno, K. 2007. “The Hygrothermal 

Performance of Wood-Framed Wall Systems Using a Relative Humidity-Dependent Vapor 

Retarder in the Pacific Northwest,” in Thermal Performance of the Exterior Envelopes of 

Buildings X, proceedings of ASHRAE THERM X, Clearwater, Florida, 

www.ornl.gov/sci/roofs+walls/staff/papers/148.pdf

IBACOS. 2002. “Moisture Issues in Homes with Brick Veneer” 

www.eere.energy.gov/buildings/building_america/pdfs/db/36397.pdf

Lstiburek, Joseph. 2004a. EEBA Builders Guides. Guides to mixed humid, hot-dry, mixeddry, and cold climates, for purchase at www.eeba.org/bookstore. 

Lstiburek, Joseph. 2004b. Roof Design, Research Report 0404, Building Science 

Corporation, www.buildingscience.com/documents/reports/rr-0404-roof-design.

Lstiburek, Joseph. 2006a. EEBA Water Management Guide, available for purchase at 

www.eeba.org/bookstore/prod-Water_Management_Guide-9.aspx 

Lstiburek, Joseph. 2006b. Understanding Drainage Planes, Building Science Digest 105, 

2006-10-24, Building Science Corporation, 

www.buildingscience.com/documents/digests/bsd-105-understanding-drainage-planes/

Lstiburek, Joseph W. 2006c. Building Science Digest 106: Understanding Vapor Barriers. 

Building Science Press. Waterford, Massachusetts. www.buildingscience.com/documents/

digests/bsd-106-understanding-vapor-barriers

Lstiburek, Joseph. 2008. Problems with Housewraps, Research Report 0106, Building 

Science Corporation, Building Science Press, 

www.buildingscience.com/documents/digests/bsd-013-rain-control-in-buildings

Lstiburek, Joseph. 2009. “The Perfect Wall,” Building Science Insight 001: 

last updated 2009/05/21, Building Science Corporation, 

www.buildingscience.com/documents/insights/bsi-001-the-perfect-wall

Lstiburek, Joseph. 2011. Dam Ice Dam, Insight 046, Feb. 2011, Building Science Corporation, 

www.buildingscience.com/documents/insights/bsi-046-dam-ice-dam/

NAHBRC. Moisture Protection of Wood Sheathing, National Association of Home Builders 

Research Center, www.toolbase.org.PDF/DesignGuides/MoistureProtectionWoodSheathing.pdf

NWPCC. 2010. Energy Efficiency: Appendix F: Model Conservation Standards, Northwest 

Power and Conservation Council., Council Document 2010-03, www.nwcouncil.org

Straube, John. 2001. “Wrapping it Up,” Canadian Architect, May 2001, 

www.cdnarchitect.com/issues/ISarticle.asp?aid=1000115982

Straube, John. 2009a. Rain Control in Buildings, Building Science Digest 013: last updated 

2009/08/10 www.buildingscience.com/documents/digests/bsd-013-rain-control-inbuildings?full_view=1 

Straube, John. 2009b. RR-0907 Ventilated Wall Claddings: Review, Field Performance, 

and Hygrothermal Modeling, Building Science Corporation www.buildingscience.com/

documents/reports/rr-0907-ventilated-wall-claddings-review-performance-modeling/view

University of Illinois Extension Office. “Five Steps to a Healthier Garage.” 

http://web.extension.uiuc.edu/will/factsheets/family116.html

Traditional roof trusses pinch insulation 

where the roof meets the walls

Raised heel or energy trusses allow 

even the corners of the attic to be well 

insulated; this helps to prevent ice dams 

in winter and keeps rooms cooler in 

summer. 

Some builders use cantilevered trusses 

to get full height insulation over the 

exterior wall. 

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.28 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Window and Door Assemblies

Choosing highly efficient windows will add expense to your project 

but will increase comfort, durability, and energy savings. The National 

Fenestration Rating Council (www.nfrc.org) provides window labeling 

that includes the following performance information:

•	 U-factor measures heat transfer—the lower the U-factor, the better 

the window performs at stopping heat flow. U-factors are the inverse 

of R-values, which measure a material’s insulation effectiveness. 

U-factor values for windows generally fall between 0.20 and 1.2. 

[2009 IECC 402 requires a maximum U-factor of 0.35 with no SHGC 

requirement specified for IECC climate zones 5-8.]

• Solar heat gain coefficient (SHGC) measures how well the window 

blocks heat caused by sunlight—the lower the SHGC rating, the 

less solar heat the window transmits. This rating is expressed as a 

fraction between 0 and 1.

• Visible transmittance (VT) measures how much light comes 

through a window. VT is expressed as a number between 0 and 1

—the bigger the number, the more clear the glass.

• Air leakage through a window assembly (AL rating) is expressed 

as the equivalent cubic feet of air passing through a square foot 

of window area (cfm/ft2)—the lower the AL, the less the window 

leaks. A typical rating is 0.2. [Per the 2009 IECC 402.4.4, windows, 

skylights, and sliding glass doors should have an air-infiltration rate of 

≤ 0.3 cfm/ft2 and swinging doors of ≤ 0.5 cfm/ft2.]

ENERGY STAR qualifies windows based on climate zones and 

divides the United States into four climate zones. See the charts and 

map for U-factor and SHGC guidelines for cold climate states.

The DOE-sponsored Efficient Windows Collaborative operates 

a website that can help designers and consumers choose windows 

(www.efficientwindows.org/index.cfm). The website includes a tool 

that allows users to analyze energy costs and savings for windows with 

different ratings. The website also has fact sheets with comparisons 

for each state.

Example of a window label from the 

National Fenestration Rating Council 

and ENERGY STAR.

RDI could not find a triple-pane window 

that was affordable enough to use in all of 

the windows for its affordable-rate homes in 

western Massachusetts, so it settled on two 

window types. For south-facing windows, a 

double-pane window with a U-value of 0.26, 

an SHGC of 0.37, and a low-emissivity coating 

on the third (inside) surface was installed. 

For north, east, and west-facing windows, 

RDI selected a triple-pane window with low-e 

coatings on the second and fifth surfaces, a 

U-value of 0.18, and an SHGC of 0.23.

8.29

CHAPTER 8. BUILDING ENVELOPE SUB-ASSEMBLIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 8.29
ENERGY STAR Qualified Windows, Doors, and Skylights 

Eligibility Criteria (Version 5.0, 04/07/2009, effective 01/04/2010)

For More Information on Windows and Doors

American Architectural Manufacturers Association. “Product Certification – Search now 

for AAMA-Certified Products (windows and doors).” Available at 

www.aamanet.org/general.asp?sect=2&id=127 

ASTM. ASTM E2112 - 07. Standard Practice for Installation of Exterior Windows, Doors and 

Skylights, www.astm.org/Standards/E2112.htm 

Carmody, John, Stephen Selkowitz, Dariush Arasteh, and Lisa Heschong. 2000. 

Residential Windows: A Guide to New Technologies and Energy Performance. 

W.W. Norton & Company, Inc., New York. 

ENERGY STAR Efficient Windows Collaborative www.efficientwindows.org/energystar.cfm 

ENERGY STAR. Residential Windows, Doors, and Skylights. 

www.energystar.gov/index.cfm?c=windows_doors.pr_windows 

FMA/AAMA 100-07. “Standard Practice for the Installation of Windows with Flanges or 

Mounting Fins in Wood Frame Construction.” Available from AAMA’s online store at 

www.aamanetstore.org/pubstore/ProductResults.asp?cat=0&src=100

Insulating Glass Manufacturers Alliance. www.igmaonline.org/content.php?doc=142

National Fenestration Rating Council. www.nfrc.org

Code/Above Code 

Window U Factor and 

Solar Heat Gain Coefficient 

A comparison of the 2009 IECC climate 

zones 5–8 and Building America 

recommendations

Code U-Factor SHGC

2009 IECC 0.35 NR

IECC 5 0.35 NR

IECC 6 0.35 NR

IECC 7&8 0.35 NR

Above Code

Building America 

Recommendations

≤ 0.30

Double glazing 

or triple

≤ 0.35

NR - No Requirement

SHGC - solar heat gain coefficient

CHAPTER 8 / BUILDING AMERICA BEST PRACTICES SERIES

8.30 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
A home’s mechanical systems can have a significant impact on 

its energy performance and comfort. As envelope performance 

improves, these systems are becoming more important targets for 

improved efficiency. The charts below show typical energy usage for 

the equipment described in this chapter, including HVAC (heating, 

ventilation, and air conditioning), plumbing and water heating, 

lighting, and appliances. 

Heating, Ventilation, 

and Air Conditioning (HVAC)

Using Building America 

best practices for insulation, 

windows, and air sealing 

can improve building 

envelope performance to 

such an extent that HVAC 

system size can sometimes 

be cut in half and still meet 

occupant comfort needs. 

Builders may be surprised 

to find that properly sizing 

the HVAC system increases 

comfort while providing 

a remarkable opportunity 

for dollar savings in highperformance homes.

Chapter 9.

Mechanical, Plumbing 

and Electrical Systems

A centrally located manifold water 

distribution system saves energy by 

reducing hot water usage.

CHAPTER TOPICS

9.1 Heating, Ventilation and 

Air Conditioning (HVAC)

9.16 Plumbing and Water Heating

9.22 High-Performance Lighting

9.24 Appliances

9.24 HVAC Commissioning

2005 Typical Residential On-Site 

Energy Consumption End Uses 

in the Western United States

(Figure source: DOE. 2008. 2008 Buildings 

Energy Data Book, based on delivered 

energy end-uses for an average household 

in the west.)

0

50

100

150

200

250

300

Benchmark 40%

(Mbtu/yr)

Appliance & Misc.

Lighting

Cooling

Heating

Hot Water

A Comparison of Energy Usage by End Use for a Home Built to 

Perform with 40% Energy Savings Compared to the Building America 

Benchmark (a home built to MEC 1993) in the Cold Climate. Example 

based on a 2-story, 1,354 ft2 house in Pasco, WA. Analysis by BIRA.

44.3%

15.9%

7.9%

15.5%

7%

4.4%

Cooling

Water Heating

Lighting

Refrigeration

Other 

Appliances

& Electronics

Heating

Energy End-Use

9.1

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.1
For the best results in comfort, efficiency, and durability, HVAC and 

duct design must be integrated in the overall architectural design. 

Builders should work closely with their HVAC engineer to properly 

size and select the HVAC equipment, design and install ducts, and 

provide appropriate ventilation. [The 2009 IECC 403.1 requires that 

forced air furnaces come with a programmable thermostat and that heat 

pumps with electric resistance backup heat be equipped with controls 

that prevent the supplemental heater from coming on when the heat 

pump compressor can meet the load.] These steps will go a long way 

toward improved energy efficiency, comfort, and cost savings.

Heating and Cooling Equipment

A well-designed house should have an HVAC system properly sized 

to its demands. The Air Conditioning Contractors of America 

(ACCA) has published simple but effective methods for determining 

loads and sizing of ductwork and heating and cooling equipment 

(available for purchase at www.acca.org). 

•	 MANUAL S guides you through the 

selection of appropriate heating and 

cooling equipment to meet identified loads.

•	 MANUAL J tells you how to calculate 

heating and cooling loads. 

•	 MANUAL D tells you how to size ducts.

•	 MANUAL T gives you the basics of 

air distribution for small buildings. 

•	 MANUAL RS focuses on comfort, 

air quality, and efficiency.

[The 2009 IECC 403.6 mandates that heating and cooling equipment be 

sized in accordance with the 2009 IRC M1401.3, which cites ACCA Manuals 

S and J for equipment sizing and load calculations. Equipment serving 

multiple dwelling units should comply with 2009 IECC 503 and 504 for 

commercial buildings, rather than 403 for residential buildings.]

One estimate states that a Manual J calculation takes about 30 

to 60 minutes for an average home, using the measurements from 

construction drawings. Manual S calculations require an additional 

15 to 30 minutes (SBIC 2003). A single calculation can work for 

multiple uses of the same plans.

Right sizing of HVAC equipment 

using Manual J calculations can 

minimize energy use and save 

upfront costs.

Efficiency Measures for Air 

Conditioners, Heat Pumps, 

and Furnaces

Seasonal Energy Efficiency Ratio (SEER)

is a measure of equipment energy 

efficiency over the cooling season. It 

represents the total cooling of a central 

air-conditioner or heat pump (in Btu) 

during the normal cooling season as 

compared to the total electric energy 

input (in watt-hours) consumed during 

the same period. Heat pumps and air 

conditioners must have a SEER of 13 or 

higher (per Federal requirements that 

went into effect in 2006).

Heating Season Performance Factor 

(HSPF) is a measure of a heat pump’s 

energy efficiency over one heating 

season. It represents the total heating 

output of a heat pump (including 

supplementary electric heat) during 

the normal heating season (in Btu) 

as compared to the total electricity 

consumed (in watt-hours) during the 

same period. Heat pumps and furnaces 

must have an HSPF of 7.7 or higher 

(per Federal requirements that went 

into effect in 2006).

Annual Fuel Utilization Efficiency 

(AFUE) measures the amount of fuel 

converted to heat at the furnace outlet in 

proportion to the amount of fuel entering 

the furnace. This is commonly expressed 

as a percentage. A furnace with an AFUE 

of 90 could be said to be 90% efficient.

Energy Efficiency Rating (EER)

a rating of a central air conditioner’s 

steady-state efficiency at 80°F indoors 

and 95°F outdoors, measured once the 

air conditioner is up and running.

DOE is mandated by Congress 

to continually review and update 

appliance efficiency standards. For 

a schedule of appliance standards 

updates, see www.standardsasap.org/

federal.htm

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Central Gas-Fired Furnaces

For central gas-fired heating systems, high-efficiency (≥90% AFUE) 

variable-speed sealed combustion gas furnaces should be installed. Sealed 

combustion means than an appliance acquires all air for combustion 

through a dedicated sealed passage from the outside to a sealed 

combustion chamber, and all combustion products are vented to the 

outside through a separate, dedicated sealed vent. Sealed combustion 

appliances eliminate the potential for back-drafting. Look for ENERGY 

STAR-qualified furnaces, heat pumps, and air conditioners. Variable 

speed motors, also known as electrically commutated motors (ECMs), 

are more efficient than regular furnace blower motors because they 

can operate at variable speeds allowing enabling the speed to adjust 

to the heating and cooling needs of the house. Instead of repeatedly 

blasting on and shutting off, the variable speed motor runs the blower 

for longer periods at lower speeds, providing quieter operation, and more 

even heat and cooling. They can be more effective at reducing humidity 

levels in a home than a central HVAC with a single-stage blower.

For larger homes (> 2,500 ft2

) and multi-storied homes, the system 

can be equipped with zoning dampers and controls to provide heat 

and cooling only where it is needed. With better insulation and air 

sealing, heating and cooling loads are decreased and even large 

homes can often be adequately served with one unit where the 

builder might have specified two or more units in the past.

Electric Heating and Heat Pumps

Electric furnaces, electric baseboard heating, and electric resistance 

wall units are all used in the cold climate but they are expensive and 

inefficient methods for heating. One recent study reported electric 

furnace heating costs $2.56/100,000 Btus and electric resistance 

heating costs of $2.05/100,000 Btus, compared to $1.49/100,000 Btus 

for gas heat and $0.82 /100,000 Btus for ductless heat pumps (based 

on fuel costs of $0.07/kWh electric, and $1.10/therm gas) (Pratt 2008).

Heat pumps are preferable to electric resistance heating. A standard 

heat pump unit with a Heating Seasonal Performance Factor 

(HSPF) of 7.7 or more (the minimum HSPF required by law as of 

September 2006), can reduce electricity consumption during heating 

by 30% or more relative to electric resistance heating systems. In 

colder areas when temperatures fall below 30°F, standard air source 

heat pumps typically use an electric resistance back-up system to 

properly heat a home. This can be a costly method of supplemental 

heating; a backup gas furnace may be a cost-effective alternative. 

Heat pumps also provide cooling; per Federal requirements since 

2006, heat pumps and air conditioners must have a Seasonal Energy 

Efficiency Ratio (SEER) of 13 or higher.

How Standard Heat Pumps Work

In cooling mode, an air-source heat pump 

evaporates a refrigerant in the indoor 

coil; as the liquid evaporates it pulls heat 

from the air in the house. After the gas is 

compressed, it passes into the outdoor 

coil and condenses, releasing heat to the 

outside air. The pressure changes caused 

by the compressor and the expansion 

valve allow the gas to condense at a high 

temperature outside and evaporate at a 

lower temperature indoors.

In heating mode, an air-source heat pump 

evaporates a refrigerant in the outdoor 

coil. As the liquid evaporates, it pulls 

heat from the outside air. After the gas is 

compressed, it passes into the indoor coil 

and condenses, releasing heat to the inside 

of the house. The pressure changes caused 

by the compressor and the expansion 

valve allow the gas to evaporate at a low 

temperature outside and condense at a 

higher temperature indoors. In cooling 

mode, the reverse happens.

9.3

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.3
Ductless Heat Pumps

Ductless heat pumps are a more efficient alternative to standard heat 

pumps which use ducts and a large blower to distribute the hot or 

cool air. Ductless heat pumps are sometimes referred to as mini-split 

heat pumps because they consist of a single outside compressor/

condenser unit connected to one or more wall- or ceiling-mounted 

indoor air handler units to provide zone heating and cooling without 

ducts. The indoor air handlers have dimensions of approximately 

12x9x31 inches and weigh as little as 25 pounds. The outdoor units 

are approximately 25x12x31 and weigh about 88 pounds. The 

outdoor units are mounted on a concrete pad outside the house; 

tubing connects the two units through a small hole in the wall. 

Ductless heat pumps have been used in Asia and Europe since the 1970s 

and in U.S. commercial buildings since the 1980s, but they are not 

yet well known in the U.S. residential market. They are 25% to 50% 

more efficient than electric baseboard or wall heaters (NEEA 2009). 

Ductless heat pumps provide increased energy savings over standard 

heat pumps in several ways – because they are ductless and 

mounted inside conditioned space, there are no losses to the attic or 

crawlspace or through leaky ducts; they provide zonal heating; and 

advances in technology in recent years have increased performance 

to the point that HSPF 12/SEER 26 units are now available. 

These high-performing heat pumps also perform at a much wider 

temperature range than standard heat pumps: some models can 

operate at an outdoor temperature range of 5°F to 75°F for heating 

and 14°F to 115°F for cooling, eliminating or significantly reducing 

the need for backup heat sources in many locations. 

These ductless heat pumps use an inverter-driven compressor 

technology coupled with a multi-speed or inverter-driven fan to 

continuously match the heating/cooling load. Unlike conventional 

air conditioning/heating systems that stop and start repetitively, the 

inverter technology adjusts the motor speed, allowing the system 

to adapt more smoothly to shifts in demand with less temperature 

variation and much lower energy use. When maximum capacity isn’t 

needed, compressor revolution and power decreases, increasing energy 

efficiency. For example, one model reports a capacity range of 3,100-

24,000 Btu’s in heating mode and 3,800-14,500 Btu’s in cooling mode.

For more information on ductless heat pumps, including installation 

tips, production selection recommendations, and performance details, 

see the website for the Northwest Ductless Heat Pump Project (www.

newductles.com), conducted by Bonneville Power Administration and 

Northwest Energy Efficiency Alliance (NEEA) (Bonneville Power 

Ductless heat pumps mount to the wall 

to provide zonal heating and cooling with 

exceptional energy performance.

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Administration 2010; NEEZ 2009). Begun in 2008, as of February 

2011, the project had 9,276 ductless heat pumps installed in Northwest 

homes, 87 participating utilities, and 746 participating contractors; 

research results on energy savings will be out in 2012.

Ground-Source Heat Pumps

Geothermal or ground-source heat pumps can be very efficient for 

heating and cooling because they use the constant temperature of the 

earth as the exchange medium instead of the outside air temperature. 

This allows the system to reach fairly high efficiencies (300%-600%) on 

the coldest of winter nights, compared to 175%-250% for air-source 

heat pumps on cool days. The disadvantages are their initial cost and 

the need for yard space to install the piping. For more information on 

various HVAC technologies, see www.energysavers.gov.

Hydronic Heating

Hydronic heating is particularly suitable for space heating in the cold 

climate in areas where there is no need for air conditioning (and its 

associated duct systems). The water can be heated by a gas or oil 

boiler, ground-source heat pump, or solar water heater. The heated 

water typically heats the home via a radiant floor system or baseboard 

convection units. [If a radiant floor system is selected in a slab-on-grade 

installation, the 2009 IECC 402.2.8 requires that the slab edge be 

insulated to R-15 that extends down and out from the building or in under 

the slab a total of 2 or 4 feet, depending on whether the home is located 

in IECC climate region 5 (2 feet) or 6 or 7 (4 feet).] Building America 

recommends R-15 perimeter insulation, plus R-20 underneath the 

entire slab. If the hot water serves a fan coil and ducted system, the 

ducts should be sealed and insulated. 

Cooling Equipment

The cooling system is shorter in the cold and very cold climates. In a 

well-insulated home, summer heat may be adequately controlled by 

ventilation combined with passive design to minimize summer solar 

heat gain (overhangs, covered porches, awnings, window blinds or 

shades, and planting of deciduous trees on the south side of homes). 

Mechanical cooling options include central air conditioning as part 

of a central gas or electric furnace system, wall unit air conditioners, 

and heat pumps. Evaporative cooling is not recommended except 

in dry regions. Heat pumps are more efficient than standard electric 

air conditioning and new models of ductless heat pumps offer 

SEER ratings as high as 26 at a wide temperature range. For either 

system, it is important to verify that the refrigerant level is correct at 

installation. The EPA reports that 75% of installed air conditioners 

had the wrong amount of refrigerant when tested. Incorrect 

Building America recommends a MERV 8 

or higher filter on the HVAC return. MERV 

(Minimum Efficiency Reporting Value) 

is a measure of an air filter’s efficiency 

at removing particles. [This exceeds the 

ASHRAE 62.2-2010 6.7 recommended 

MERV 6 or better.]

Hydronic heating in condominiums in 

Aspen, Colorado, uses water that is 

preheated by solar thermal panels, than 

heated by a gas boiler, and distributed via 

baseboard radiators.

9.5

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.5
refrigerant levels can lower efficiency by 5% to 20% and can cause 

premature component failure, resulting in costly repairs (see EPA 

Heating and Cooling Refrigerant Charging guidelines www.epa.gov). 

Other Heating and Cooling Options

The superior insulation and air sealing of high-performance 

homes can reduce heating and cooling demand to such a degree 

that options not typically thought of as energy efficient become 

acceptable because they can be sized small enough to meet the 

small demand: for example closed-combustion gas space heaters or 

electric zonal heating systems. Another option is integrated heating 

systems, which combine space heating, water heating, heat-recovery 

ventilation, and air conditioning. The heating input for these systems 

could be gas, heat pump, or solar. 

For More Information on Heating and Cooling Equipment 

Air Conditioning Contractors of America. 2007. ACCA Standard 5; HVAC Quality Installation 

Specification, ANSI/ACCA 5 QI-2007, Air Conditioning Contractors of America, 2800 

Shirlington Road, Suite 300, Arlington, VA. www.acca.org

Air Conditioning Contractors of America. Manual J: Residential Load Calculation, Eighth 

Edition. ACCA, Arlington, VA. www.acca.org

Air Conditioning Contractors of America. Manual S: Residential Equipment Selection. ACCA, 

Arlington, VA. www.acca.org

ASHRAE. 2007. Standard 52.2-2007, Method of Testing General Ventilation Air-Cleaning 

Devices for Removal Efficiency by Particle Size, available for purchase from ASHRAE’s 

bookstore www.ashrae.org 

Baylon, David, Kevin Geraghty, and Kacie Bedney. 2010. “Performance of Ductless Heat 

Pumps in the Pacific Northwest,” in Proceedings of the 2010 ACEEE Summer Study on Energy 

Efficiency in Buildings, prepared by Ecotope Inc. and Bonneville Power Administration.

Bonneville Power Administration. 2010. Residential Ductless Mini-Split Heat Pump Retrofit 

Monitoring: 2008-2010 Analysis, prepared for BPA by Ecotope, www.bpa.gov/energy/N/DHP.cfm

Building Industry Institute. Procedures for HVAC System Installation.

www.thebii.org/hvac.pdf

Consortium for Advanced Residential Buildings. Steven Winter Associates, Inc. (CARBSWA). Designing Forced-Air HVAC Systems. www.carb-swa.com/Resources

Consortium for Energy Efficiency (CEE) and the Air-Conditioning, Heating, and 

Refrigeration Institute (AHRI). “Database of Qualifying ENERGY STAR Heat Pumps and Air 

Conditioners,” www.ceehvacdirectory.org

Consortium for Energy Efficiency. Residential HVAC: CEE-AHRI HVAC Directory.

www.cee1.org/resid/rs-ac/rs-ac-main.php3

Cowan, Laura. 2009. “How Heat Pumps Work.” May 13, 2009. 

http://home.howstuffworks.com/home-improvement/heating-and-cooling/heat-pump.htm

DOE. “Energy Savers – Heating Systems,” U.S. Department of Energy. www.energysavers.gov

DOE. “How to Size HVAC Systems Correctly,” U.S. Department of Energy Building Energy 

Codes Resource Center, http://resourcecenter.pnl.gov/cocoon/morf/ResourceCenter/article/137

DOE. “Right-Size Heating and Cooling Equipment,” U.S. Department of Energy Technology 

Fact Sheet, www.toolbase.org/Design-Construction-Guides/HVAC/right-size-hvac-equipment 

This high-efficiency, sealed-combustion 

gas space heater heats the entire home 

at low installation and operating cost.

Low-Cost System Matches 

Super-Efficient Homes’ Low 

Heat Load with Savings for 

Homeowners and Builder

When Rural Development, Inc., 

worked with Building America’s CARB 

research team to design 20 energyefficient, affordable duplexes in western 

Massachusetts, the designs they came 

up with were so well insulated that most 

furnace systems were too large for the 

design heat load of the 1,100-1,700-ft2

homes. Instead RDI installed a small, 

natural gas-fired space heater on the first 

floor of each home. The sealed combustion 

heater has a capacity of 10,200 Btu per 

hour on low fire and 16,000 Btu/hr on 

high fire with an annualized fuel utilization 

efficiency (AFUE) of 83%. Compared to 

the hydronic baseboard systems they had 

used on previous homes, the builder saved 

$5,000 per unit. There is no traditional 

duct system with this type of space heater. 

To heat the upstairs bedrooms, CARB 

designed a system using an exhaust fan 

in the living room ceiling to pull warm air 

into the bedrooms.

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
DOE. 2008. 2008 Buildings Energy Databook. U.S. Department of Energy, 

http://buildingsdatabook.eren.doe.gov/ 

EPA. “Heating and Cooling: Sizing and Installation – Proper Refrigerant Charging,” 

U.S. Environmental Protection Agency. www.energystar.gov/index.cfm?c=heat_cool.

pr_properly_sized

Furnace Filter Care. “Understanding MERV Ratings,” 

www.furnacefiltercare.com/merv-ratings.php

NEEA. 2009. Northwest Ductless Heat Pump Project: Project Overview and Installation 

Best Practices, Northwest Energy Efficiency Alliance, www.nwductless.com/contractors/

project-resources

Pratt. 2008. Ductless Heat Pumps, BPA Brown Bag Presentation prepared by Jeffrey R. Pratt 

Inc. for Bonneville Power Administration, www.bpa.gov/energy/n/Utilities_Sharing_EE/

Energy_Smart_Awareness/pdf/BPA_DHP_Presentation_022708.pdf

Sustainable Buildings Industry Council (SBIC). 2003. Green Building Guidelines: Meeting 

the Demand for Low-Energy, Resource-Efficient Homes. U.S. DOE. Washington, D.C. 

Ducts and Air Handlers

Duct System Design and Layout

With central forced-air systems, the gas or electric furnace and 

ducts are often located in unconditioned space in the attic, garage, 

crawlspace, or unheated basement. As typically installed, this 

“default” design is assumed in codes to reduce system efficiency by 

about 20%; whereas placing ducts in conditioned space is assumed 

to cut air loss to about 4% (ICC 2006 as reported in Lubliner et al. 

2008). Numerous studies have shown significant savings from moving 

the ducts and airhandler into conditioned space. In a modeling study 

conducted in Spokane, Washington, by Building America research 

partner Washington State Energy Office, using a home built to the 

current Washington State Energy code, moving ducts out of a vented 

crawlspace and into the home resulted in heating energy savings of 

28.4% and cooling savings of 17% (Hales et al. 2010). 

As data confirm, the best practice is to locate the ducts in conditioned 

space so that any leakage that does occur will send air to or draw 

air from conditioned space. Ducts may be run through open-web 

floor trusses in a two-story home; through a dropped hallway ceiling 

in a one-story home; or through a conditioned attic, conditioned 

crawlspace, or conditioned basement. Ducts should not be located in 

exterior walls. Air handlers should be located in conditioned space, 

such as a closet inside the home, in a conditioned attic or basement, 

or in an air-sealed and conditioned closet in the garage. 

In all cases, duct systems should be designed using ACCA Manual D

[2009 IRC M1601.1]; duct runs should be as short as possible, and duct 

sizes and layouts should be shown on plans. Building cavities should 

not be used as supply ducts [2009 IECC 403.2.3].

Duct Run Configurations

Here are three example designs for putting 

ducts in conditioned space.

(Source: Building Science Corporation)

9.7

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.7
Keeping ducts and air handlers inside conditioned space typically 

impacts architectural design and should be considered early in the 

design process. Duct chases or dropped soffits may require 

thinking through the sequence of how trade contractors will do 

the installation. 

The Seattle-area production builder Quadrant Homes worked 

with Bob’s Heating in Kirkland, Washington, to design systems 

that brought the furnace and ducts into conditioned space. “It is 

easier for installers to do a quality job when they are not lying in 

the mud, deep in a corner of the crawlspace,” said Wade Craig of 

Bob’s Heating. When ducts are installed between floors, they are 

clearly visible to the general contractor and inspector, encouraging 

better installations. Another major concern is “trade damage” which 

can occur if electrical or plumbing subcontractors compromise 

ducts to squeeze their wires and pipes into the same space. With 

open-web trusses there is enough room for all trades, making each 

subcontractor’s work easier. 

Craig said his firm can lower its bid when the HVAC system is 

moved inside. Additionally, Craig points out that moving the furnace 

from the attic to a mechanical closet on the second floor facilitates 

easier equipment servicing and improves worker safety during 

installation and retrofits. Quadrant is aware of the potential for 

air leakage pathways between floors and the need to reduce those 

pathways via proper insulation and air sealing of the rim joists. All 

ducts in Quadrant homes are well sealed with mastic and tested with 

a Duct BlasterTM (Lubliner et al. 2008).

If ducts are not in conditioned space, one alternative is to locate 

the ducts on the ceiling deck of an unconditioned attic and “bury” 

the ducts with blown-in insulation. In more humid climates this 

strategy is not recommended because condensation could occur 

at the duct exterior surface. Building America researchers have 

investigated burying ducts in attic insulation above ceilings and 

based on this research, buried ducts may be permissible but the 

ducts should be directly insulated to R-8, apart from the piled-on 

insulation. Building America does not recommend using the buried 

duct approach in climates where the summertime attic dew point 

temperature is often above 60°F, or if the Jul-Aug monthly average 

outdoor dew point temperature is above 60°F (refer to Table 6-3 of 

ASHRAE Standard 90.2-1993). The mixed-humid and hot-humid 

climates often exceed this dew point and so buried ducts are 

specifically not recommended there. In other climates, such as cold 

climates up through the humid river valleys, builders and designers 

should be cautious.

(Top and Bottom) These Building America 

builders run ducts through open-web floor 

trusses to keep the ducts in conditioned 

space (shown here). Open-web trusses 

allow subcontractors the flexibility to run 

plumbing, electrical, and ductwork easily 

between floors, with little to no “trade 

damage” or “trade fighting.” Air handlers 

are located in conditioned space in the 

home or in an air-sealed closet in the garage.

“We literally designed the house 

around the HVAC system.”

Eric Jester, East Liberty Development, Inc.

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Locating air handlers and return ducts in the garage is not 

recommended because of the potential for drawing carbon monoxide 

and hazardous fumes into the home. If the air handler must be located 

in the garage, it should be enclosed in an insulated, air-sealed closet. 

Ducts located in the garage may not have any openings in the garage 

[2009 IRC R302.5.2] and furnaces and air handlers that supply air to 

living spaces shall not supply air to or return air from a garage [2009 

IRC M1601.6]. The air handler and any return-air ductwork should be 

thoroughly sealed with UL 181B-M-compliant mastic, with a target 

leakage between the duct system and the garage of 0 CFM @25 Pa. 

Duct Sealing and Insulating

Leaky duct systems cause energy losses, but they can also depressurize 

the house, which can pull outdoor, unfiltered air into the house from 

attics, crawlspaces, attached garages, and through building walls. 

All ducts, air handlers, and filter boxes should be airsealed and joints 

and seams should comply with the 2009 IRC M1601.4.1. The 2009 IRC 

describes several UL 181-approved sealing methods. Building America 

recommends water-based mastic that complies with UL181B-M, 

as appropriate. Duct-drywall connections should be sealed with 

caulk or foam sealant. Leaky ductwork in an unconditioned attic or 

crawlspace not only leaks energy but it can also draw unhealthy air 

into the air distribution system. Sealing ducts with mastic is desirable 

even for ducts located in conditioned spaces. Properly sealed ducts 

make sure air gets to the rooms intended, rather than leaking into 

a plenum space. It also minimizes the chances of creating pressure 

differentials from room to room, can cause drafts. The double-check 

inherent in the process of sealing each joint reduces the chances of 

unconnected ductwork, which is a surprisingly common mistake. 

Although mastic is the most reliable duct sealing method, the 

2009 IRC M1601.4.1 allows certain approved tapes and DOE research 

has found that some tapes perform adequately for sealing ducts, 

particularly fiberglass board ducts (see sidebar). However, highperformance tapes may be difficult to identify and traditional duct 

tape (cloth-backed rubber adhesive tape) should never be used 

to seal ducts, even if it meets UL ratings. Tapes have low tensile 

strength and should not be used to mechanically support ducts. 

If the ducts are placed in unconditioned spaces, 10% to 30% of 

the energy used to cool the air can be lost to conduction through 

the duct surfaces due to the extreme summer temperatures in these 

spaces. Supply ducts in attics should be insulated to R-8 minimum 

and all other ducts should be insulated to R-6 minimum; insulation 

is not required for ducts located inside the building’s thermal 

envelope [per 2009 IECC 403.2]. 

(1) One technique for placing ducts in 

conditioned space is to run a duct chase in a 

dropped ceiling down the main hallway of the 

house with registers off the sides for each room. 

This technique allows for compact duct design.

(2) This finished house shows registers 

going directly from a main duct chase in 

the dropped hallway ceiling.

(3) This air handler closet is located in the 

garage space but is isolated with thermal 

and air barriers.

9.9

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.9
Duct air tightness should be verified with duct blaster pressure testing. 

[The 2009 IECC 403.2 requires that ducts be tested for air tightness 

and allows for the testing to occur either before drywall is put up or 

after drywall is put up. If tested at pre-drywall or rough-in, they must 

be ≤ 6 cfm per 100 ft2 of conditioned floor area at 25 Pa; if tested after 

construction, than ≤ 8 cfm at 25 Pa. (If the airhandler and all ducts are 

in conditioned space, duct leakage testing is not required.)] Building 

America recommends testing at rough-in when leaks can be easily 

accessed and sealed.

For More Information on Duct Layout and Sealing

2009 IECC. 2009. International Energy Conservation Code, Section 403.2.2 “Sealing,” 

and “Table 4.4.5.2(.2) – Default distribution system efficiencies for the proposed design.” 

International Code Council (ICC), Washington, D.C. www.iccsafe.org/Store/Pages

2009 IRC. 2009. International Residential Code - One and Two-Family Dwellings, 

International Code Council (ICC), Washington, D.C. www.iccsafe.org/Store/Pages

Air Conditioning Contractors of America (ACCA). Manual D: Residential Duct Systems. 

ACCA, Arlington, VA. www.acca.org

Air Conditioning Contractors of America. Manual T: Air Distribution Basics for Residential 

and Small Commercial Buildings. ACCA, Arlington, VA. www.acca.org

California Energy Commission. 2003. Home Builders Guide to Ducts in Conditioned Space.

P500-03-82-A16. www.sabreargentina.com/downloads/FinalAttachments/A-16_Bldrs_

Guide_Ducts_6.3.4.pdf

California Energy Commission. 2005. 2005 Building Energy Efficiency Standards: 

Residential Compliance Manual. CEC-400-2005-005-CMF. Sacramento, CA. 

www.energy.ca.gov/title24/2005standards/residential_manual.html#4Q

D. Griffiths, M. Zuluaga, D. Springer, and R. Aldrich. 2004. “Insulation Buried Attic Ducts – 

Analysis and Field Evaluation Findings.” American Council for an Energy-Efficient Economy 

(ACEEE). 2004 ACEEE Summer Study on Energy Efficiency in Buildings. Pacific Grove, CA. 

August 23, 2004.

DOE. 2004. Better Duct Systems for Home Heating and Cooling, NREL/BR-550-30506; DOE/

GO-102004-1606. U.S. DOE Building America Program, www.buildingamerica.gov

FSEC. Designing and Building Interior Duct Systems, FSEC-PF-365-01. Florida Solar Energy 

Center, http://securedb.fsec.ucf.edu/pub/pub_show_detail?v_pub_id=4013

Hales, David and David Baylon. 2010. “Moving ducts into conditioned space: getting to code 

in the Pacific Northwest,” ASHRAE Transactions, report # 3616

Hedrick, R. 2003. Home Builders Guide to Ducts in the Conditioned Space, California Energy 

Commission, 200-03-082-A16, www.energy.ca.gov/pier/project_reports/500-03-082.html

HGTVPro.com. “How to Seal Ductwork,” www.hgtvpro.com/hpro/bp_mechanical/article/0,,

HPRO_20151_4583390,00.html

Lubliner, Michael, Ryan Kerr, Andy Gordon, and Chuck Murray. 2008. “Moving Ducts Inside: 

Big Builders, Scientists Find Common Ground,” In Proceeding of the 2008 ACEEE Summer 

Study on Energy Efficiency in Buildings, www.energy.wsu.edu/documents/code/ACEEE_

Ducts_Inside.pdf

McIlvaine, j.R., D. Beal, and P. W. Fairey III. 2002. Design and Construction of Interior 

Duct Systems. Florida Solar Energy Center, Cocoa, Florida, FSEC-PF-365-01, 

www.baihp.org/pubs/pdf/interior_ducts.pdf. 

Regional Technical Forum (RTF). 2006. Deemed Savings for New Construction Homes.

Portland, OR.

Sherman, M, and I. Walker. 1998. “Can Duct Tape Take the Heat?” Home Energy Magazine, 

Berkeley, California. http://homeenergy.org/archive/hem.dis.anl.gov/eehem/98/980710.html

(Bottom) Mastic provides the most reliable 

duct sealing method. Ducts should be 

located in conditioned space. 

(Photo source: BAIHP)

Standards for Duct Sealants

Underwriter Laboratories, Inc. (UL) 

publishes several standards that relate 

to duct sealants, the most important of 

which is UL 181. It deals with ducts in 

general; UL 181A covers field-assembled 

duct-board and UL 181B covers flex duct 

systems. Each standard includes test 

procedures for sealants. Duct tapes and 

packing tapes that pass UL 181B are labeled 

“UL 181B-FX.” Mastics can pass 181A or B 

and are labeled “UL 181A-M” or “UL 181BM.” Foil tapes are designated with a P. 

Most tapes that are labeled 181B-FX are 

duct tapes. UL 181A and 181B appear to 

do a good job of testing for safety, tensile 

strength, and initial adhesion. However, 

they may not do a good job of rating how 

well sealants seal typical duct leaks or 

how well they stay sealed under 

normal conditions.

California Title 24 residential building 

standards require that duct sealants meet 

UL 181, UL 181A, UL 181B, or UL 723 (for 

aerosol sealants). The California Energy 

Commission has approved a cloth-backed 

duct tape with a special butyl adhesive 

(CEC 2005). Metal ducts are to be sealed 

with UL 181 mastic. For duct board, UL 

181 tapes are accepted. For flex duct, a 

combination of UL 181 mastic and strap 

ties should be used.

Adapted from Sherman and Walker 1998.

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.10 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Pressure Balancing

Pressure imbalances from indoors to outdoors or room to room 

can draw moisture-laden air into wall cavities. Imbalanced airflows 

can also cause drafts and temperature differences between rooms or 

floors, leading to comfort complaints. 

One key factor in eliminating pressure imbalances is providing 

an adequate return air path to the air handler. Four methods for 

providing a return air path are as follows: 1) ducted returns from 

each room to the air handler; 2) room-to-room ceiling jump ducts; 

3) transfer grilles or transoms; and 4) door undercuts. Door undercuts 

are not recommended by Building America because they are often too 

small and/or are blocked by the installation of carpeting. 

Sound transmission in jump ducts or transfer grilles can be minimized 

by the use of flex duct, duct lining with sound-absorbent material, a 

slightly circuitous path, or some combination of these strategies.

(Figure source: Building Science Corporation)

Examples of Jump Ducts and Transfer Grilles for Pressure Balancing

9.11

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.11
For More Information on Pressure Balancing in Homes

Associated Air Balance Council. AABC National Standards for Total System Balance. 2002. 

www.aabchq.com/resources/national.aspx

National Environmental Balancing Bureau (NEBB). Section 15990 - Testing, Adjusting, 

and Balancing. www.nebb.org/tabspec.htm

Air Distribution Fans

Fan motors on HVAC equipment can have a large impact on 

year-round energy use because they are often shared by heating, 

cooling, and ventilation systems. Nearly all furnace manufacturers 

offer “variable-speed” brushless permanent magnet (BPM) direct 

current motors. These motors have higher efficiency and, unlike 

permanent split-capacitor motors, BPM motors retain their high 

efficiency at reduced fan speeds. Although BPM motors may have a 

price premium of $200 or more, they are a recommended means of 

lowering HVAC energy use, and are required for two-stage heating 

and cooling systems. Some types also maintain a constant air flow as 

filters become dirty or registers are closed.

Ventilation

Building America recommends that all new homes be equipped with 

whole-house mechanical ventilation that complies with ASHRAE 

62.2. Mechanical ventilation systems for indoor air quality include 

exhaust-only fans, supply-only systems, and balanced systems. 

Mechanically balanced systems use heat and energy recovery 

ventilators; semi-balanced systems use a combination of exhaust 

and supply techniques.

(left) Installing jump ducts from room to 

room is one way to balance pressures. 

(Photo source: IBACOS)

(right) Transfer grilles help balance air 

pressure between rooms, which helps to 

minimize drafts and comfort complaints. 

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.12 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Supply-Only Ventilation Systems 

A supply-only ventilation system brings outside air to the intake side of 

a home’s central air handler. A central fan-integrated supply ventilation 

system uses an exterior air intake that is ducted to the return air side 

of the HVAC system. Code requires that outdoor air intakes and 

exhausts should be equipped with automatic or gravity dampers that 

close when the ventilation system is not in operation [2009 IECC 403.5]. 

Building America recommends that electronic controls be added, 

including a motorized damper and timer to open the damper in sync 

with operation of the HVAC fan for automatic ventilation of the home 

at regular intervals throughout the day. Advantages to this system 

are that the fresh air volume can be adjusted to meet ASHRAE 62.2 

requirements, outside air is filtered, and fresh air is delivered to every 

space (Russell, Sherman, and Rudd 2006). A disadvantage of supplyonly ventilation is that it can positively pressurize the home. 

Supply-only ventilation is not recommended if the fan has a 

standard one-speed motor because the fan will blow too much air 

and use too much energy. (One-speed air handler fans can blow up 

to 1400 cfm when 50 to 100 cfm is desired for ventilation.) Central 

fan-integrated ventilation works well when the central fan has an 

energy-efficient variable-speed ECM motor and the system is installed 

by a knowledgeable contractor who understands how to program the 

blower operation. 

When a supply system is used for ventilation and it is sized to meet 

ASHRAE 62.2 ventilation rates, Building America partner Building 

Science Corporation recommends that, to avoid the potential for cold 

air complaints, not more than 125 cubic feet per minute (CFM) be 

supplied at one location in bedrooms and not more than 500 cfm at 

registers in other rooms. Often this means that an 8-inch to 10-inch 

supply to the master bedroom needs to be split up to two 6-inch or 

7-inch supplies. Comfort complaints increase if the homeowners set 

their thermostat too low (e.g., below 70oF); because the air will be 

blowing cooler more often. One means for avoiding these comfort 

issues is to install an HRV or ERV that uses a heat exchanger to 

condition the circulating air, as described below.

Exhaust-Only Ventilation

Continuously operating an exhaust fan located in a bathroom or central 

area of the house provides low-cost ventilation that meets ASHRAE 

62.2. High-quality, quiet, efficient fans that have separate speeds for 

ventilation and exhaust are typically used for this application. A better 

solution than an isolated exhaust fan is to tie all bathroom exhaust 

ducts together and route them through a single, continuously operating, 

high-efficacy axial fan that is vented to the home’s exterior. 

ASHRAE 62.2

In 2003, the American Society of 

Heating, Refrigerating and AirConditioning Engineers (ASHRAE) 

established a new standard for 

indoor ventilation in residences. The 

standard is ASHRAE 62.2, Ventilation 

for Acceptable Indoor Air Quality 

in Low-Rise Residential Buildings 

(ASHRAE 2003). The Standard is on 

a three-year publishing cycle and has 

been republished in 2004, 2007, and 

2010 with minor updates. The following 

information is adapted from the forward 

that is published with the Standard:

The three primary requirements involve 

whole-house ventilation, local exhaust, and 

source control. Whole-house ventilation 

is intended to dilute the unavoidable 

contaminant emissions from people, 

materials, and background processes. Local 

exhaust is intended to remove contaminants 

from specific rooms, such as kitchens and 

bathrooms. Source control measures are 

included to deal with other anticipated 

sources. The standard’s secondary 

requirements focus on properties of specific 

items, such as sound and flow ratings 

for fans and labeling requirements. The 

standard is principally about mechanical 

ventilation, but its purpose is to provide 

acceptable indoor air quality.

ASHRAE Standard 62.2 requires a 

continuous ventilation rate of 1 cfm 

per 100 ft2

 of building area plus 

7.5 cfm x (# bedrooms +1). An intermittent 

fan can meet this requirement if the airflow 

rate is adjusted upward based on specific 

ventilation effectiveness requirements 

published in the standard.

9.13

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.13
Exhaust fans help to improve indoor air quality by removing air 

contaminants near their source, such as moisture from a shower. 

Because exhaust fans draw air from leaks in the building envelope, air 

is not filtered, will not be evenly distributed, and comes from unknown 

sources. Another concern with exhaust-only ventilation systems is that 

exhaust systems (which include bath fans, kitchen range fans, and clothes 

dryers) draw air out of a home, creating a negative pressure in the home. 

In an inefficient, leaky home, this negative pressure pulls outside air 

in through cracks around doors and windows and leaks in walls. In a 

high-performance home, those air leaks have been sealed up so a fresh 

air intake must be added to the home to supply fresh air. Failing to 

provide an outside air intake can cause the home to become negatively 

pressurized. This can increase the risk of backdrafting any atmosphericvented combustion (fuel-burning) appliances or fireplaces that may be 

in the home. Backdrafting occurs when the flue’s natural ability to draw 

combustion fumes out of the house is overpowered and, instead, these 

fumes (including carbon monoxide) are pulled into the house. Negative 

pressure in a house can also draw in hot outside air, soil gases, garage 

fumes, and pollens.

Balanced Systems

Heat recovery ventilators (HRVs) and energy recovery (or 

enthalpy-recovery) ventilators (ERVs) both provide a controlled 

way of ventilating a home while minimizing energy loss by using 

conditioned exhaust air to warm or cool fresh incoming air. These 

ventilators are typically whole-house systems that share the furnace 

duct system or have their own duct system. 

The main difference between an HRV and an ERV is the way the 

heat exchanger works. With an ERV, the heat exchanger transfers 

water vapor along with heat energy, while an HRV only transfers 

heat. The ERV helps keep indoor humidity more constant. 

Most energy recovery ventilation systems can recover about 70%–

80% of the energy in the exiting air. They are most cost-effective in 

climates with extreme winters or summers and where fuel costs are 

high. Consider these recommendations for selecting an HRV or ERV 

(Holladay 2010b): 

•	 For a small, tight house in a cold climate—especially a house with 

a large family—choose an HRV. 

•	 For a large house in a cold climate—especially a house with few 

occupants—choose an ERV. 

•	 In a hot, humid climate, know that an ERV will cost a little less to 

operate during the summer than an HRV. 

Balanced ventilation system using a fresh air 

intake integrated with HVAC air handler for 

supply air and exhaust fans. 

Balanced ventilation system with heat 

recovery via an air-to-air heat exchanger. 

(Source: Lstiburek 2004)

Provide bathroom and kitchen exhaust 

fans. Duct them to the outside and caulk 

ducts at the dry wall for an air-tight seal. 

Use low-sone fans for quiet operation.

Crawlspace

with mastic

CAULK

EXHAUST FAN If fan exhausts or 

draws air through 

sidewall, install hood

with louvered 

damper

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed; inside seam 

taped and mudded

GARAGE

Bottom plate caulked

or gasketed to subfloor

 on interior, exterior,

or both surfaces

Drywall caulked, 

glued or gasketed 

to top plate on interior, 

exterior, or both surfaces 

CAVITY

Continuous bead of

sealant or adhesive

Thin sheet goods 

as draftstop behind

tub or enclosure

Blocking

Solid air barrier

material sealed

at perimeter

CAULK

Use caulk or adhesive to

seal panels to joists at seams

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.14 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
•	 In mixed climates, choose either appliance. 

•	 Understand the most important quality is energy efficiency. 

•	 Find an installer who understands how ERVs and HRVs work 

and knows how to install them properly.

“Semi-Balanced” System

A lower-cost alternative is a “semi-balanced” system consisting of 

a combination of the supply and exhaust systems described above. 

While two of the builders that Building America worked with on 

these 40% cold best practices chose to install energy recovery or heat 

recovery ventilators (Devoted Builders and Shaw Construction) two 

of the builders chose a semi-balanced system (Nelson Construction 

and S&A Homes) and one chose exhaust-only (RDI). Nelson 

Construction in Hamilton, Connecticut, decided on a semi-balanced 

approach that brings outside air into the home through a duct to 

the return side of the air handler. A flow regulator opens the damper 

at regular intervals in sync with the fan blower, which circulates the 

fresh air through the house. Stale air is exhausted through a fan in an 

upstairs bathroom. This 1-sone-rated fan is connected to the main 

space with a 6-inch jump duct. To prevent air pressure imbalances, the 

laundry room has a transfer grille installed to provide pressure relief 

during dryer operation.

Ventilation for Night Time Cooling

Air conditioning energy use can be significantly reduced by 

ventilating homes with cool night air. Ventilation cooling is practical 

in locations where temperature swings of 30° or more between day 

and night and summer daytime highs above 80°F are common. 

The simplest form is opening windows at night, but security 

concerns may prohibit obtaining sufficient window area to provide 

effective ventilation. Two automated systems have been developed 

by Building America research partner Davis Energy Group that 

ventilate and cool the house with outside air. The systems, called 

SmartVent and NightBreeze, use the HVAC system fan coupled with 

an outside air intake damper and controlled by temperature sensors 

to provide filtered outside air without the homeowner having to 

open windows (Hoeschele 2008). 

Nelson Construction attached a fresh air 

intake with a timed mechanical damper 

controller to regulate fresh air flow into 

the return plenum of the HVAC air handler. 

The damper can be set to open allowing 

fresh air to be pulled into the air handler 

by the air handler fan, also operated by the 

timer. This draws fresh air into the house 

at regular intervals. When combined with 

timed exhaust fans, this provides low-cost 

balanced ventilation.

9.15

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.15
For More Information on Ventilation Systems

2009 IECC. 2009. International Energy Conservation Code, Section 403.5, “Mechanical 

Ventilation,” Section 403.6, “Equipment Sizing,” International Code Council (ICC), 

Washington, DC. www.iccsafe.org/Store/Pages

2009 IRC. 2009. International Residential Code - One and Two-Family Dwellings, Section 

M1502.1 “Clothes Dryer Exhaust – General,” International Code Council (ICC), Washington, 

DC. www.iccsafe.org/Store/Pages

Air Conditioning Contractors of America. Manual T. Air Distribution Basics for Residential 

and Small Commercial Buildings. ACCA, Arlington, VA. www.acca.org

ASHRAE Standard 62.2-2010 Ventilation and Acceptable Indoor Air Quality in 

Low-Rise Residential Buildings (ANSI/ASHRAE Approved) can be previewed at 

www.ashrae.org/technology/page/548

Building Energy Codes Resource Center “Whole-House Mechanical Ventilation – 

Code Notes,” U.S. Department of Energy, http://resourcecenter.pnl.gov/cocoon/morf/

ResourceCenter/article/1467

ENERGY STAR Thermal Bypass Checklist Guide, 2008, available at www.energystar.gov/ia/

partners/bldrs_lenders_raters/downloads/TBC_Guide_062507.pdf, pg. 13

Hoeschele, Marc. 2008. Development of an Integrated Residential Heating, Ventilation, 

Cooling, and Dehumidification System for Residences, Prepared by Davis Energy Group 

for the U.S. Department of Energy, www.davisenergy.com/docs/FinalReport_SBIR2_IHVCD_061808.pdf

Holladay, Martin. 2010a. “Designing a Good Ventilation System: Ventilating Is Easy — It’s 

Ventilating Right That’s Hard,” Green Building Advisor.com posted June 15, 2010. 

www.greenbuildingadvisor.com/blogs/dept/musings/designing-good-ventilation-system

Holladay, Martin. 2010b. “HRV or ERV? Choosing the right equipment for a balanced 

ventilation system,” Green Building Advisor.com posted January 22, 2010. 

www.greenbuildingadvisor.com/blogs/dept/musings/hrv-or-erv

HVI. 2006. “Fresh Ideas in Residential Ventilation.” Home Ventilating Institute. Wauconda, IL. 

www.hvi.org/resourcelibrary/HomeVentGuideArticles.html

Lawrence Berkeley National Laboratory. Thermal Energy Distribution Website at 

http://ducts.lbl.gov

Minnesota Department of Commerce Energy Information Center. June 23, 2008. 

“Maintain home ventilation systems to provide healthy air supply.” Available at www.state.

mn.us/portal/mn/jsp/common/content/include/contentitem.jsp?contentid=536886092

NAHB Research Center. “Whole-House Mechanical Ventilation Strategies,” 

www.toolbase.org/Technology-Inventory/HVAC/whole-house-mechanical-ventilation

Piazza, T., R.H. Lee, M. Sherman, and P. Price. 2007. Study of Ventilation Practices and 

Household Characteristics in New California Homes. CEC-500-2007-033. California Energy 

Commission, Sacramento, CA., www.energy.cq.gov/2007publications/CEC-500-2007-033/

CEC-500-2007-033.PDF

Rudd, Armin. 2006. Ventilation Guide. Building Science Press Inc., Energy & Environmental 

Building Association, Minneapolis, MN, available for purchase at 

www.eeba.org/bookstore/prod-Ventilation_Guide-10.aspx

Russell, Marion, Max Sherman and Armin Rudd. 2007. “Review of Residential Ventilation 

Technologies.” HVAC&R Research, Vol. 13, No. 2, p. 325-348, March 2007. ASHRAE. 

http://findarticles.com/p/articles/mi_m5PRD/is_2_13/ai_n25007553

U.S. Environmental Protection Agency. 2009. Indoor airPLUS Construction Specifications, 

www.epa.gov/indoorairplus/index.html

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.16 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Plumbing and Water Heating

Residential hot water energy use accounts for approximately 19% of 

the residential energy consumed in the United States, according to 

the Energy Information Administration. In new, high-performance 

homes, hot water energy accounts for a higher percentage, typically 

21% to 32%. Hot water systems don’t use more energy than they 

used to but they take a relatively larger share of the energy use in 

homes because in tighter houses less energy is required to heat and 

cool the homes than in older homes built to less stringent standards. 

There are several measures builders can take to reduce the amount 

of energy needed for water heating: 

•	 Install high-efficiency electric or gas water heaters. Specify sealedcombustion, power-vented, or direct-vented gas water heaters. 

These models save energy and reduce the risk of backdrafting 

flue gases into the house.

•	 Consider alternative technologies like tankless gas or electric 

water heaters, solar thermal water heaters, and ground source 

heat pumps and desuperheaters.

•	 Insulate hot water supply lines to R-4 and install tanks that have 

at least R-12. [2009 IECC 403.3 requires R-3 minimum.]

•	 Consolidate bathrooms and other hot water-consuming activities 

into the same area(s) of the house.

•	 Place the water heater in a central location inside the home to 

minimize piping trunk lengths. Use a central manifold 

distribution system.

•	 Locate plumbing pipes in the attic and cover with insulation in 

single-story, slab-on-grade homes. Locate the pipes in interstitial 

space between floors for multi-story homes.

•	 Do not install plumbing in exterior walls. 

•	 Do not oversize piping. Use code-permitted minimums. Bigger 

isn’t better.

•	 Do not use continuous recirculation pumps. If recirculating 

pumps are specified, the pumps should be controlled by timers 

or on-demand to stop continuous operation.

•	 Seal around plumbing penetrations in all exterior surfaces, 

surfaces that border on unconditioned spaces, and between floors. 

Use fire-resistant sealant in plates between floors.

In an NAHB Research Center study, the 

central manifold hot water distribution 

system provided hot water to the fixtures 

more quickly than traditional trunk 

and branch and remote manifold 

distribution methods.

Code/Above Code 

Water Pipe Insulation

A comparison of the 2009 Uniform 

Plumbing Code, state codes, and Building 

America recommendations

Code

2009 Uniform 

Plumbing Code

R-3 insulation for hot 

or cold piping outside 

conditioned space

Above Code

Building America 

Recommendations

Insulate all piping 

inside and outside 

of conditioned 

space to R-4

9.17

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.17
Hot Water Distribution

Essentially there are three types of hot water distribution systems: 

1) the traditional “trunk and branch” with a large main line 

feeding smaller pipes that then flow directly to fixtures or split to 

serve multiple fixtures; 2) the central manifold (homerun) where 

the water heater feeds a manifold with dedicated lines running to 

each household fixture; and 3) the remote manifold system, which 

includes trunk lines that run to remote manifolds that serve clusters 

of fixtures, such as in one or more bathrooms or a kitchen.

The NAHB Research Center tested the three water distribution 

systems—trunk and branch, central manifold, and remote manifold—

and found that, while all three supplied sufficient flow, the central 

manifold system provided the quickest hot water to the fixtures and 

the most stable pressure when multiple fixtures were used. 

Common plumbing pipe materials are copper and PEX (cross-linked 

polyethylene). PEX installation can save labor and materials and 

can be cost competitive with rigid pipe systems. The NAHBRC 

points out that because PEX piping will not corrode and resists 

scale buildup, maintenance costs may be lower than for rigid piping. 

Fewer leaks are possible because fewer connections are required.

PEX piping should not connect directly to a hot water tank or solar 

water heater where the temperature of the water could exceed 200°F. 

PEX piping should not be used in installations subject to continual 

ultraviolet light exposure.

Hot Water Circulation Pumps and Controls

Do not use continuous recirculation systems for hot water. These 

systems keep hot water continuously flowing through pipes and result 

in substantial heat loss. If solar thermal water heating systems are 

used, the flow-through solar collectors should always be kept separate 

from any hot water recirculation systems. 

If recirculation systems are used, install a push-button control, which 

will minimize the energy penalty associated with recirculation systems 

and insulate the pipe to R-2 [per 2009 IECC 403.4]. An on-demand 

system recirculates the water through the hot water tank only when 

hot water is needed. This system helps eliminate wasted water 

down the drain and is best suited for fixtures located far from the 

water heater. On-demand recirculators do not save energy except in 

comparison to continuous recirculation systems. 

Hot Water Distribution Systems

HEATER MANIFOLD

BATH II

KITCHEN

UTILITY

ROOM

BATH I

UTILITY

ROOM

KITCHEN BATH II

Traditional Trunk System

More Efficient Manifold System

BATH I

HEATER

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.18 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Water Heaters

Performance rating information for conventional storage water 

heaters, electric heat pumps, and tankless water heaters is available 

from the Air-Conditioning, Heating, and Refrigeration Institute 

(AHRI) (www.ahrinet.org). AHRI’s members include appliance 

manufacturers that use all fuel types. Performance rating information 

for solar thermal collectors and systems is available from the Solar 

Rating and Certification Corporation (www.solar-rating.org). 

Five types of ENERGY STAR-qualified water heaters are now 

available: high-efficiency gas storage, gas condensing, gas tankless, 

solar, and heat pump water heaters. (For lists of qualifying products, 

see www.energystar.gov/index.cfm?c=water_heat.pr_water_heaters.)

Conventional Storage Water Heaters

Conventional gas or electric storage water heaters offer a ready 

reservoir (storage tank) of hot water. The lowest-priced storage water 

heater may be the most expensive to operate and maintain over its 

lifetime. While an oversized unit may be alluring, it carries a higher 

purchase price and increased energy costs due to higher standby 

energy losses. Information on properly sizing a water heater is 

available on the DOE Energy Savers website www.energysavers.gov. 

Storage heaters work best with steady, continuous use patterns.

The minimum efficiency target for gas combustion storage water 

heaters is 0.60 or higher. These heaters should be either power vented, 

which forcibly discharges the products of combustion and draws 

combustion air from the house; direct vented with dedicated outside 

air for combustion; or sealed combustion units that draw combustion 

air from outdoors and fan discharge combustion exhaust outdoors.

Electric storage heaters are generally the most expensive to operate 

unless rates are very low. Builders should specify the most efficient unit 

possible and consider the use of solar thermal systems, a propanefired instantaneous water heater, or a heat pump water heater.

Tankless Water Heaters

Tankless water heaters provide hot water only as it is needed. They have 

no tank and so do not have the standby energy losses associated 

with storage water heaters. Typically, tankless water heaters provide 

hot water at a rate of 2 to 5 gallons (7.6–15.2 liters) per minute. If the 

demand for hot water does not exceed the heater’s ability to produce it, 

tankless water heaters do not run out of hot water. Gas-fired tankless 

water heaters produce higher flow rates than electric tankless heaters. 

Because of their heat-on-demand nature, electric versions can create 

The tankless gas-fired water heaters 

installed by Nelson Construction in 

Farmington, Connecticut, save energy by 

eliminating the stand-by losses inherent 

with storage tank water heaters.

9.19

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.19
high peak loads for electric utilities. In areas where utilities charge more 

for electricity at peak times, these systems could be especially expensive 

for consumers. 

Gas-fired tankless water heaters have been tried in many Building 

America homes. They are readily available and are a mature 

technology. In addition to energy savings, other benefits include small 

size and longer life expectancy. One disadvantage of these units is the 

time needed for a cold unit to reach operating temperature. This brief 

warm-up time results in a slight delay in hot water delivery (10 to 20 

seconds) and associated water waste. Builders considering installing 

tankless gas water heaters in a development need to plan for adequate 

gas line size. Tankless water heaters draw approximately 150,000 

BTUs compared to a standard water heater that draws 35,000 BTUs. 

Therefore, much higher capacity is demanded of the gas lines during 

peak usage times, such as in the morning.

Heat Pump Water Heaters

Air source heat pump water heaters use electric compressors and 

pumps to move heat from the environment to the water tank. 

Although they use electricity, they can be two to three times more 

energy efficient than conventional electric resistance water heaters. 

One manufacturer estimates $320 savings per year in water heating 

costs when comparing their ENERGY STAR heat pump water heater, 

which uses 1,856 kWh/yr, to a standard 50-gallon electric tank water 

heater, which uses 4,881 kWh/yr. 

Because the heat pump water heater draws in air from the room to 

heat water, some manufacturers recommend that the room the water 

heater is located in be at least 10 ft x 10 ft x 7 ft (700 cubic feet) or 

larger. If the room is smaller than 700 cubic feet, the room must have 

a louvered door or a door that has vents installed near the top and 

bottom of the door. Each of these vents should have an area of 240 

square inches. The units themselves are approximately 63 inches tall 

by 24 inches wide. 

Because they have a fan, heat pump water heaters do make some 

noise; noise is related to fan speed, the faster the fan speed the more 

sound is likely. Fans speeds will increase when ambient temperatures 

are colder and when tank temperature is lower. The heat pump water 

heater can be located in a utility room inside the home or in a heated 

basement. The water heater, pipes, and condensate lines should be 

protected from freezing temperatures. The water heater may add 

slightly to heating loads in the winter because it pulls some heat from 

the air but it will also help reduce cooling loads in the summer 

in the area of the home where it is located. 

Heat pump water heaters are now 

commercially available like this one seen 

at the 2010 International Builders Show.

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.20 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
One concern with heat pump water heaters is their recovery rate. The 

water heater industry typically measures the recovery rate of a water 

heater by its first hour delivery (FHD) of hot water. Natural gas 

and liquid propane water heaters are capable of heating water more 

quickly than electric water heaters (standard electric or heat pump), 

and therefore, have quicker recovery rates. A 50-gallon gas water 

heater has a FHD of 80-90 gallons. A 50-gallon electric standard 

or heat pump water heater has a FHD of 58-65 gallons. Many heat 

pump water heaters are hybrid models that use electric elements to 

provide back-up heat. These can assist with recovery rates. Another 

solution is to get a slightly larger tank than you would typically size, 

for example a 50-gallon rather than 40-gallon tank.

Geothermal heat pumps can also be used to heat water. These 

systems draw heat from the ground during the winter and carry heat 

away from the indoor air during the summer. For water heating, 

a desuperheater can be added to a geothermal heat pump system. 

A desuperheater is a small, auxiliary heat exchanger that uses 

superheated gases from the heat pump’s compressor to heat water. 

This hot water then circulates through a pipe to the home’s storage 

water heater tank. 

Desuperheaters can assist both tank and tankless water heaters. In 

the summer, when the geothermal heat pump runs frequently, it may 

meet all of a home’s hot water demand. During the fall, winter, and 

spring, when the desuperheater isn’t producing as much excess heat, 

backup from a storage or tankless water heater may be needed.

Ground-source (geothermal) heat pump water heaters can be effective 

in all climate zones, but they are complex and require a skilled installer. 

Also, the pricing varies dramatically by region. In an area where no 

natural gas is available, this system may be a good option.

Solar Water Heaters

Solar thermal water heaters use the sun’s heat to provide hot water. 

These systems usually include one or two collectors that typically sit 

on a house’s roof and resemble skylights. Four types of collectors 

work well for heating water:

•	 Glazed flat-plate collectors are the most common and can be used 

in any climate with proper design.

•	 Evacuated tube collectors use thermos-like evacuated glass tubes. 

Some also use heat pipes with a special fluid that vaporizes at high 

temperatures. These collectors tend to be more expensive than 

other collectors but operate efficiently at high temperatures and 

can be used in very cold climates with proper design.

P/T

Relief

Valve

Air Eliminator

Shut-Off Valve

Air Vent

Fill/Drain

Assembly

Check Valve

HOT WATER OUT

Heat Exchanger

Controller

Circulator Pump

Expansion

Tank

Pressure

Relief Valve

Pressure

Gauge

Tank

Sensor

Collector

Sensor

COLD WATER IN

Evacuated tube collectors are one solar 

water heater type that works well in 

cold climates.

This solar water heater uses propylene 

glycol (antifreeze) in the exposed 

collector, making it safe for use when 

temperatures are below freezing. The 

glycol loop heats up on the roof then 

passes through the tank of potable 

water to release its heat then it is 

pumped back to the roof to reheat. 

9.21

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.21
•	 Integrated collector storage systems combine a collector with a 

storage tank. These systems are one of the lowest cost but should 

only be used where there is no chance of freezing. They should not 

be used in the cold climate.

•	 Unglazed flat plate collectors are simple systems that consist of plastic 

surfaces incorporating channels for water to flow through. Some 

manufacturers are offering unglazed collectors for domestic hot water. 

Their traditional use has been for pool and spa heating. Every swimming 

pool with a solar exposure should be equipped with a solar pool heater.

Tankless Coil and Indirect Water Heaters

Two technologies that use the home’s space heating furnace to also heat 

water are the tankless coil heater and the indirect water heater. Tankless 

coil water heaters provide hot water on demand without a tank. Because 

they rely on the homes’ space heating furnace to heat the water, they are 

most efficient from an energy perspective in homes where the furnace 

is on often, such as northern parts of the cold climate. Indirect water 

heaters also use the space heating furnace but instead of heating water 

directly the furnace heats a fluid that in turn heats water in a water storage 

tank via a heat exchanger. Because the tank allows for heating with less 

turning the furnace on and off, indirect water heaters are more efficient.

For More Information on Plumbing and Water Heating

DOE. 2007. Volume 6 - Building America Best Practices Series – High Performance Home 

Technologies: Solar Thermal & Photovoltaic Systems. Washington, D.C. www.buildingamerica.gov

DOE. 2007. A Consumer’s Guide to Energy Efficiency and Renewable Energy. 

“Water Heating,” DOE Energy Efficiency and Renewable Energy 

www.eere.energy.gov/consumer/your_home/water_heating/index.cfm/mytopic=12770

DOE. 2011. “Sizing Water Heaters,” Energy Savers, U.S. Department of Energy, 

www.energysavers.gov

ENERGY STAR. High-Efficiency Water Heaters Provide Hot Water for Less. U.S. 

Environmental Protection Agency, Washington, D.C. www.energystar.gov/ia/new_homes/

features/WaterHtrs_062906.pdf

2009 IRC. 2009. International Residential Code - One and Two-Family Dwellings, Section 

403.4, “Circulating Hot Water Systems,” International Code Council (ICC), Washington, D.C. 

www.iccsafe.org/Store/Pages

National Association of Home Builders Research Center (NAHBRC). Undated. Toolbase 

Technotes. Cross-Linked Polyethylene PEX in Residential Plumbing Systems. 

www.toolbase.org/PDF/DesignGuides/TechNote_Pex.pdf

Solar Rating and Certification Corporation, www.solar-rating.org.

Wiehagen J. and J.L. Sikora. 2003. Performance Comparison of Residential Hot Water 

Systems. NREL/SR-550-32922. National Renewable Energy Laboratory. Golden, CO. 

www.buildingamerica.gov

Energy-efficient ENERGY STAR-rated 

fixtures come in many attractive styles, 

like these CFL-based fixtures. 

(Photo source: Progress Lighting)

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.22 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
High-Performance Lighting

Lighting accounts for an estimated 15% of electricity use in the 

typical American home (DOE 2009). The typical incandescent lamp 

wastes 90% of the energy it uses producing heat rather than light. 

High-performance lighting, including CFL and LED products, 

provides excellent visual quality that is also very energy efficient. 

Compact fluorescent lamps (CFLs) use 70%-75% less energy than 

their incandescent equivalents with comparable brightness and 

color rendition. They cost more, but last 10 to 13 times longer than 

incandescent lamps, making them cost effective if used at least 

2-3 hours per day. Compact fluorescent lamps come in both pinbased models and screw-based models that fit most standard fixtures 

found in homes today. ENERGY STAR first established criteria 

for CFL lamps in 2007. Today thousands of models of ENERGY 

STAR-labeled CFL bulbs and fixtures are available in a wide variety 

of sizes, shapes, and color renditions. 

Light emitting diode (LED) lights are becoming more commonplace 

as new models are developed with better lighting performance, higher 

efficiency, and lower cost. DOE tracks and tests LED products as 

they enter the market via its CALiPER program and other lighting 

programs (see www.ssl.energy.gov). ENERGY STAR criteria for 

solid-state lighting (LED) went into effect in September 2008. To earn 

the ENERGY STAR label, LED products have to offer a three-year 

warranty and meet stringent performance requirements for color 

rendering, luminaire efficiency, and light output over the life of the 

lamp, which is at least 25,000 hours for indoor, residential products.

[The 2009 IECC 404 requires that at least 50% of the lamps in 

permanently installed lighting fixtures be high-efficacy lamps.] It is 

likely this requirement will be raised to 75% in the 2012 IECC. 

Building America recommends 100% high-efficacy lamps. Almost all 

fluorescent lamps equipped with electronic ballasts qualify as highefficacy light sources. LEDs and metal halide lamps can also be high 

efficacy. Incandescent, quartz halogen, low-voltage halogen MR, 

and mercury vapor lamps do not qualify as high efficacy. 

Recessed “can” ceiling fixtures, or downlights, that are recessed into 

insulated ceilings are required [by the 2009 IECC 402.4.5] to be rated 

for insulation contact (so that insulation can be placed over them). 

The housing of the fixture should be airtight to prevent conditioned 

air from escaping into the ceiling cavity or attic, and unconditioned air 

from infiltrating from the ceiling or attic into the conditioned space. 

[Per the 2009 IECC 402.4.5] the fixture should bear a label showing it 

meets the ASTM E 283 guideline of ≤2.0 cfm of air movement from 

These CFL-based lights designed by Maxlite 

won grand prize in the 2008 Lighting 

for Tomorrow design competition cosponsored by DOE. (Photo source: Maxlite)

LED fixtures are becoming more efficient 

and affordable and are now available in 

several applications for homes like the 

under-cabinet, in-cabinet, and spot 

lighting shown here.

9.23

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.23
the conditioned space to the ceiling cavity when tested at 75 Pa and 

the housing should be caulked or gasketed where it meets the ceiling. 

IC-rated downlight fixtures are available for CFL lamps.

DOE partners with lighting organizations to host three CFL and 

LED lighting design competitions. Visit the competition websites to 

see competition winners, including some of the most energy-efficient, 

eye-catching designs on the market: Lighting for Tomorrow 

(www.lightingfortomorrow.com), Next Generation Luminaires 

(www.ngldc.org), and the L-Prize (www.lightingprize.org). 

Residential lighting controls represent a significant opportunity for 

energy savings. Lighting controls generally refer to technologies that 

turn off (or turn down) lighting systems when they are not needed. 

Examples include occupancy sensors, vacancy sensors, photo 

sensors, dimmers, and timers.

Example of Recessed Downlight Performance Using 

Different Lighting Sources

MEASURE

INCANDESCENT* FLUORESCENT* LED**

65W R-30 Halogen

13W triple 

tube Spiral 

CFL

15W R-30 

CFL

LR6 LED 

downlight 

by Cree

Delivered light output 

(lumens), initial 678 466 653 697

Luminaire wattage 

(nominal W) 65 10 13 6.4

Luminaire efficacy

(lm/W) 11 46 49 109

Price (average prices 

as of Aug 2009) $3 $8 $5 $80

Life Span 2,500 hrs 12,000 hrs 6,000 hrs 50,000 hrs

*Based on photometric and lamp lumen rating data for products available 

July 2010. Actual downlight performance depends on reflectors, trims, lamp 

positioning, and other factors. Assumptions available from PNNL.

**LED tested through DOE CALiPER program. For more about CALiPER, 

see www.ssl.energy.gov

For More Information on Lighting

California Energy Commission. 2009. California’s Energy Efficiency Standards for Residential 

and Nonresidential Buildings: Title 24. Sacramento, CA. www.energy.ca.gov/title24/

California Lighting Technology Center. www.cltc.ucdavis.edu

ENERGY STAR. 2007. Light Bulbs and Fixtures website. www.energystar.gov

IBACOS. High-Performance Lighting Guide website www.ibacos.com

U.S. Department of Energy. Solid-State Lighting (SSL) website www.ssl.energy.gov

LED Can Lights Give off 

650 Lumens from 6.5 Watts

This LED lamp, the LR6 LED downlight 

by Cree LED Lighting Solutions, Inc, fits 

into a standard recessed can fixture and 

provides comparable light output to CFL 

and incandescent bulbs, at lower wattage 

and much longer life. In 2010, Cree came 

out with a model that produces 697 lumens 

of light with only 6.5 Watts of power.

(Photo and Figure Source: Cree Lighting 

Solutions, Inc.)

Installation

• Designed to easily install in standard 6” 

downlight housings from Cree and other 

manufacturers.

• Quick install system utilizes a unique 

retention feature. Simply attach socket 

to LR6. Move light to ready position and 

slide into housing. Rotate module 1/4 turn 

to the right to lock in place.

• Reference www.CreeLEDLighting.com 

for a list of compatible housings

CHAPTER 9 / BUILDING AMERICA BEST PRACTICES SERIES

9.24 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Appliances

When it comes to selecting appliances and electronic equipment, 

look for the EnergyGuide and ENERGY STAR labels. Building 

America recommends using best-in-class products for appliances 

that are not currently rated by ENERGY STAR. 

EnergyGuide Label

The Federal Trade Commission requires EnergyGuide labels on 

most home appliances (except for stove ranges and ovens, and home 

electronics, such as computers, televisions, and home audio equipment). 

EnergyGuide labels provide an estimate of the product’s energy 

consumption or energy efficiency. They also show the highest and lowest 

energy consumption or efficiency estimates of similar appliance models.

ENERGY STAR Label

ENERGY STAR labels appear on appliances and 

home electronics that meet strict energy efficiency 

criteria established by the U.S. Department 

of Energy and U.S. Environmental Protection 

Agency. The ENERGY STAR labeling program 

includes most home electronics and appliances 

except for stove ranges and ovens.

For More Information on ENERGY STAR and 

EnergyGuide Labeling

California Energy Commission Consumer Energy Center “EnergyGuide,” 

www.consumerenergycenter.org/home/appliances/energyguide.html

ENERGY STAR. www.energystar.gov

ENERGY STAR Windows. www.efficientwindows.org/energystar.cfm

SRP. “Energy Guide Labels help you compare,” www.srpnet.com/energy/energyguide.aspx

The U.S. Department of Energy “Best Practices” Builders Guides

 www.eere.energy.gov/buildings/building_america/

A refrigerator labeled with both the ENERGY 

STAR label and the EnergyGuide label.

The EnergyGuide label helps 

consumers compare the 

energy efficiency of appliances

Estimated energy consumption 

on a scale showing a range for 

similar models

Estimated yearly operating cost 

based on the national average cost 

of electricity.

9.25

CHAPTER 9. MECHANICAL, PLUMBING AND ELECTRICAL SYSTEMS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 9.25
Chapter 10.

Occupant Health 

and Safety

As houses become tighter, indoor air quality becomes a more 

important issue. To address occupant health and safety, the EPA 

has developed an Indoor airPlus checklist, shown at the end 

of this chapter, that recommends these actions (www.epa.gov/

indoorairplus): 1) moisture control including improved control of 

condensation and better roof, wall, and foundation drainage; 2) 

radon control including testing and radon abatement techniques; 

3) pest management including caulking, sealing, and screening at 

entry points; 4) HVAC quality including a properly engineered 

system, sealed ducts, and whole-house and spot ventilation; 

5) combustion venting including sealed combustion heating 

equipment, installation of carbon monoxide detectors, and sealing 

and ventilation of attached garages; and 6) selection of low-chemicalcontent materials, keeping materials dry during construction, and 

airing out the home prior to move in. 

The following safety and health features should be included in 

house designs:

•	 Avoid installing atmospheric-venting (standard efficiency) fuelfired furnaces and water heaters in conditioned space including 

laundry rooms. These devices draw air from the room in which 

they are located and are recognizable by the “hat” or “skirt” 

around the base of the flue (where it meets the furnace or water 

heater) just above the open combustion air intake. These devices 

depend on stack effect to establish an exhaust draft, but the 

stack effect can be overcome by dryers, exhaust fans, supply duct 

leakage, or other conditions that depressurizes the house, causing 

back drafting of exhaust gases. [ASHRAE 62.2-2010, citing NFPA 54, 

permits atmospherically vented combustion appliances inside provided 

the total net flow of the two largest exhaust fans does not exceed 15 

cfm/100 ft2 of occupiable space when in operation at full capacity.]

(top) Some cabinet makers are now 

specializing in low-VOC cabinetry to meet 

growing consumer demand.

(bottom) Several low-VOC adhesives

are now available. 

Dryer vent exhausts must have a closeable 

gravity or automatic damper. A single hinged 

door with a 21⁄2-inch effective opening is not 

as effective as a louvered damper.

louvered damper

with hood

10.1

CHAPTER 10. OCCUPANT HEALTH AND SAFETY

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 10.1
•	 Use only sealed-combustion or power-vented appliances in the 

conditioned space. Specifically, Building America recommends any 

furnace inside conditioned space should be a sealed-combustion 

90%+ (AFUE of 90 or greater) unit. Any water heater inside 

conditioned space should be sealed-combustion, direct-vented, or 

power-vented.

•	 Avoid appliance models that incorporate passive combustion air 

supply openings or do not have outdoor supply air ducts directly 

connected to the appliance.

•	 Install carbon monoxide detectors (hard-wired units) (at one per 

every approximately 1,000 square feet) in any house containing 

combustion appliances and/or an attached garage, and even in 

those houses with no combustion appliances in case one should 

be installed at a future date. [NFPA 720 says CO detectors shall be 

installed near bedrooms, and on every occupiable level of a dwelling 

unit, including basements, excluding attics and crawl spaces. NFPA 101 

Section 24.3.4.1 requires smoke alarms in all sleeping rooms, outside of 

each separate sleeping area, in the immediate vicinity of the sleeping 

rooms, and on each level of the dwelling unit, including basements.]

•	 Direct vent gas cooking ranges and all exhaust fans to the outside. 

Range hoods capable of exhausting more than 400 cfm must 

provide makeup air at a rate equal to the exhaust air rate 

[2009 IRC M1503.4].

•	 Use sealed-combustion gas fireplaces that vent harmful 

combustion gases to the outside.

•	 Vent bathrooms, kitchens, toilets, and laundry rooms directly 

outdoors. Outdoor air intakes and exhausts should be equipped 

with automatic or gravity dampers that close when the ventilation 

system is not in operation [per 2009 IECC 403.5]. Kitchen fans 

should ventilate at a rate of 100 cfm intermittent or 25 cfm 

continuous; bathroom fans should ventilate at a rate of 20 cfm 

continuous or 50 cfm intermittent [2009 IRC Table M1507.3]. Use 

energy-efficient and quiet fans (see Chapter 9, ventilation section).

•	 Vent clothes dryers and central vacuum cleaners directly outdoors. 

Smooth, rigid metal ducts with louvered vents and straight runs 

provide the most efficient ducting systems. Check code [2009 IRC 

M1502.4.4] and manufacturer’s specifications for limits on duct 

length. Avoid sags in ducts. Insulate ducts to avoid condensation; 

flash and caulk wall penetrations. Vinyl, nylon, and foil ducts do 

not meet code [2009 IRC M1502].

(top) This fresh air intake has a mechanical 

damper to control the intake of fresh 

outside air into the air handler for 

distribution via the central HVAC system.

(bottom) Atmospheric venting water 

heaters, like the one shown here, can 

backdraft through the opening at the base 

of the flue. Use of closed-combustion 

appliances eliminates this risk. 

CHAPTER 10 / BUILDING AMERICA BEST PRACTICES SERIES

10.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
•	 Provide filtration for forced air systems that provide a minimum 

atmospheric dust spot efficiency of 30% or MERV of 8 or higher. 

MERV (Minimum Efficiency Reporting Value) is a measure of an 

air filter’s efficiency at removing particles. [This exceeds the ASHRAE 

62.2-2010 6.7 recommended MERV 6 or better.]

•	 Maintain indoor humidity in the range of 30% to 50% by controlled 

mechanical ventilation, mechanical cooling, or dehumidification. 

•	 Maximize hard surface areas (tile, vinyl, hardwood) to better 

manage dust for health purposes. 

• Install a central (also known as “whole-house”) vacuum system 

that exhausts to the outdoors, to facilitate cleaning and minimize 

reintroduction of vacuumed dust.

•	 Provide occupants with information on safety and health related 

to the operations and maintenance of the systems that provide 

control over space conditioning, hot water, and lighting. 

•	 Isolate attached garages from conditioned spaces [per 2009 

IECC 402.4.1 and ASHRAE 62.2-2010, 6.5.1]. Common walls and 

ceilings between attached garages and living spaces should be visually 

inspected to ensure they are air-sealed before insulation is installed. All 

connecting doors between living spaces and attached garages should 

include an automatic closer, and they should be installed with gasket 

material or be made substantially air-tight with weather stripping.

•	 Install an exhaust fan in attached garages with a minimum 

installed capacity of 70 cfm that is rated for continuous operation, 

vent the fan directly outdoors. If automatic fan controls are 

installed, they should activate the fan whenever the garage is 

occupied and for at least 1 hour after the garage has been vacated. 

The fan carries pollutants outside and creates a negative pressure 

that helps stop garage air from migrating into the house.

•	 If fireplaces are included (gas-fired or solid-fuel-burning), install 

units that have a dedicated outside air intake for combustion air, 

directly vent effluents outside, and are equipped with tight-fitting 

glass doors. 

•	 Use low-VOC (volatile organic compound) paints, finishes, 

varnishes, and adhesives whenever possible. Keep windows open 

while paints and adhesives are applied and until they are dry to 

dissipate initial concentrations.

This Building America home used low-VOC 

paints and finishes (shown in lower photo) 

to meet local green building guidelines.

American Lung Association: 

Nine Features of a Healthy House

•	 Foundation waterproofing and

moisture control

•	 Advanced framing techniques

•	 Air sealing and advanced

insulation techniques

•	 Energy-efficient,

high-performance windows

•	 Energy-efficient and sealed

combustion appliances

•	 High-efficiency air filtration

•	 Whole house ventilation

•	 Humidity control

•	 Low-VOC interior finishes.

(Source: Health House, American Lung 

Association of the Upper Midwest, www.

healthhouse.org/build/components.cfm)

10.3

CHAPTER 10. OCCUPANT HEALTH AND SAFETY

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 10.3
For More Information on Healthy Homes 

and Combustion Safety

American Lung Association. 2008. “Health House: Builder Guidelines.” ALA, Saint Paul, MN. 

www.healthhouse.org/build/2008HHbuilderguidelines.pdf

American Lung Association. “Health House Tipsheet on Backdrafting,” ALA, Saint Paul, MN. 

www.healthhouse.org/tipsheets/TS_backdrafting.pdf

ASTM D6670 – 01. 2007. “Standard for Full-Scale Chamber Determination of Volatile 

Organic Emissions from Indoor Materials/Products,” 

www.astm.org/Standards/D6670.htm

Building Performance Institute, Inc., “Combustion Safety Test Procedure for Vented 

Appliances,” 4/07. www.bpi.org/documents/Gold_Sheet.pdf

California Air Resource Board (CARB). “Airborne Toxic Control Measure (ATCM) to Reduce 

Formaldehyde Emissions from Composite Wood Products” Fact Sheet, 

www.arb.ca.gov/toxics/compwood/factsheet.pdf

California Air Resource Board (CARB). “Regulation for Reducing Volatile Organic 

Compound Emissions from Consumer Products,” available online at 

www.arb.ca.gov/consprod/regs/cp.pdf

Canadian Standards Association CSA 6.19-01. Residential Carbon Monoxide Alarming Devices. 

www.shopcsa.ca/onlinestore/GetCatalogDrillDown.asp?Parent=571

Canadian Standards Association. “Carbon Monoxide Alarms,” 

www.csa-international.org/consumers/consumer_tips?default.asp?load=carbon_

monoxide&language=english

Center for ReSource Conservation. Before you buy...Cabinets. Article available at 

www.greenerbuilding.org/buying_advice.php?cid=4

Consumer Product Safety Commission (CPSC). What You Should Know About Combustion 

Appliances and Indoor Air Pollution (CPSC Document #452), 

www.cpsc.gov/cpscpub/pubs/452.html

ENERGY STAR. 2007. ENERGY STAR Indoor Air Package Specifications, Version 2. U.S. 

Environmental Protection Agency. www.energystar.gov/ia/partners/bldrs_lenders_raters/

downloads/IAP_Specification_041907.pdf

Florida Solar Energy Center. 2007. “Indoor Air Quality,” available at 

www.fsec.ucf.edu/en/consumer/buildings/homes/airqual.htm

Greenguard Environmental Institute.

www.greenguard.org

International Code Council, Inc., “UL 2034 History – CO Alarms,” May 4, 2005. 

www.iccsafe.org/cs/cc/ctc/CO/CO_UL2034History.pdf

2009 IECC. 2009. International Energy Conservation Code, International Code Council (ICC), 

Washington, DC. www.iccsafe.org/Store/Pages

2009 IRC. 2009. International Residential Code - One and Two-Family Dwellings, Section 

M1502.4.1, “Material and Size,” and M1502.4.4 “Duct Length,” International Code Council 

(ICC), Washington, DC. www.iccsafe.org/Store/Pages

KCMA Environmental Stewardship Program 01-06. 

www.greencabinetsource.org/index.cfm?fuseaction=Defining.Welcome

National Association of Home Builders Research Center. “Low- or No-VOC Paints, Finishes 

and Adhesives,” www.toolbase.org/Home-Building-Topics/Indoor-Air-Quality/low-voc-paints

National Green Building Standard 901.10, August 10, 2007, pg. 70. 

www.nahbgreen.org/Guidelines/ansistandard.aspx

NFPA 720: Standard for the Installation of Carbon Monoxide (CO) Warning 

Equipment in Dwelling Units. www.nfpa.org/aboutthecodes/AboutTheCodes.

asp?DocNum=720&Cookie%5Ftest=1

CHAPTER 10 / BUILDING AMERICA BEST PRACTICES SERIES

10.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Raub, J. A., M. Mathieunolf, N. B. Hampson, and S. R. Thom. 2000. “Carbon Monoxide 

Poisoning—a Public Health Perspective.” Toxicology (145):1-14. 

www.ncbi.nlm.nih.gov/pubmed/10771127

South Coast Air Quality Management District. Rule 1168 – Adhesive and Sealant Application. 

www.arb.ca.gov/DRDB/SC/CURHTML/R1168.pdf

Sustainable Buildings Industry Council (SBIC). 2003. Green Building Guidelines: Meeting the 

Demand for Low-Energy, Resource-Efficient Homes. U.S. DOE. Washington, D.C. document 

available at www.sbicouncil.org/storeindex.cfm 

The American Lung Association. Health House tipsheet on carbon monoxide www.

healthhouse.org/tipsheets/TS_CarbonMonoxide.pdf

The American Society of Heating, Refrigerating, and Air-Conditioning Engineers 

(ASHRAE). Top Ten Things that homeowners can do to provide good indoor air quality. 

www.contractorconnect.net/GoodAir.html

UL 2034. 1996. Standard for Single and Multiple Station Carbon Monoxide Alarms, Edition 2, 

October 29, 1996. www.alliedsalescompany.com/ul/2034.pdf

University of Illinois Extension Service. “Five Steps to a Healthier Garage,” 

http://web.extension.uiuc.edu/will/factsheets/family116.html

U.S. Department of Energy. “The House as a System: Combustion Safety,” 

www.eere.energy.gov/buildings/building_america/pdfs/db/31046.pdf

U.S. Department of Energy. 2000. “Combustion Equipment Safety,” DOE Fact Sheet, 

May 2000. DOE/GO 10099-784. www.earthcrafthouse.com/documents/factsheets/CESCombustion-Safety%2000-784.pdf

U.S. Environmental Protection Agency. 2009. “Indoor airPLUS Construction Specifications,” 

www.epa.gov/indoorairplus

U.S. Environmental Protection Agency. “Indoor Air Quality Carbon Monoxide Fact Sheet,” 

www.epa.gov/iaq/co.html

U.S. Environmental Protection Agency. “Wood Coating Case Studies by Company,” 

www.epa.gov/ttn/atw/wood/low/casebyco.html

U.S. Green Building Council, LEED for Homes. 2008. 

www.greenhomeguide.org/documents/leed_for_homes_rating_system.pdf

10.5

CHAPTER 10. OCCUPANT HEALTH AND SAFETY

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 10.5
Indoor airPLUS Verification Checklist

Address or Div/Lot#: 

City/State/Zip: Date: Verified by

Section Requirements (see Indoor airPLUS Construction Specifications for details) N/A Builder Rater

Water-Managed Site and Foundation 

 1.1 Site & foundation drainage: sloped grade, protected drain tile, & foundation floor drains o	 o

 1.2 Capillary break below concrete slabs & in crawlspaces (Exception - see specification) o	 o	 o

 1.3 Foundation wall damp-proofed or water-proofed (Except for homes without below-grade walls) o	 o	 o

 1.4 Basements/crawlspaces insulated & conditioned (Exceptions - see specification) o	 o	 o

Water-Managed Wall Assemblies 

 1.5 Continuous drainage plane behind exterior cladding, properly flashed to foundation o	 o

 1.6 Window & door openings fully flashed o	 o

Water-Managed Roof Assemblies 

 1.7 Gutters/downspouts direct water a minimum of 5' from foundation (Except in dry climates) o	 o	 o

 1.8 Fully flashed roof/wall intersections (step & kick-out flashing) & roof penetrations o	 o

 1.9 Bituminous membrane installed at valleys & penetrations (Except in dry climates) o	 o	 o

 1.10 Ice flashing installed at eaves (Except in Climate Zones 1 - 4) o	 o	 o

Interior Water Management 

1.11 Moisture-resistant materials/protective systems installed (i.e., flooring, tub/shower backing, & piping) 	 	 	 o

1.12 No vapor barriers installed on interior side of exterior walls with high condensation potential o 	 o

1.13 No wet or water-damaged materials enclosed in building assemblies o 	 o

 2.1 Approved radon-resistant features installed (Exception - see specification) o 	 o 	 o

 2.2 Two radon test kits & instructions/guidance for follow-up actions provided for buyer (Advisory-see specification) o 	 o 	 o

 3.1 Foundation joints & penetrations sealed, including air-tight sump covers o

 3.2 Corrosion-proof rodent/bird screens installed at all openings that cannot be fully sealed (e.g., attic vents) o 	 o

 4.1 HVAC room loads calculated, documented; system design documented; coils matched o

 4.2 Duct system design documented & properly installed OR duct system tested (check box if tested) o o 	 o

 4.3 No air handling equipment or ductwork installed in garage; continuous air barrier required in adjacent assemblies o

 4.4 Rooms pressure balanced (using transfer grills or jump ducts) as required OR tested (check box if tested) o o 	 	 o

 4.5 Whole house ventilation system installed to meet ASHRAE 62.2 requirements o

 4.6 Local exhaust ventilation to outdoors installed for baths, kitchen, clothes dryers, central vacuum system, etc. o

 4.7 Central forced-air HVAC system(s) have minimum MERV 8 filter, no filter bypass, & no ozone generators o

 4.8 Additional dehumidification system(s) or central HVAC dehumidification controls installed (In warm-humid climates only) o 	 	 o

Combustion Source Controls 

 5.1 Gas heat direct vented; oil heat & water heaters power vented or direct vented (Exceptions - see specifications) o 	 	 o

 5.2 Fireplaces/heating stoves vented outdoors & meet emissions/efficiency standards/restrictions o 	 	 o

 5.3 Certified CO alarms installed in each sleeping zone (e.g., common hallway) according to NFPA 720 o

 5.4 Smoking prohibited in common areas; outside smoking at least 25' from building openings (Multi-family homes only) o 	 o 	 o

Attached Garage Isolation 

 5.5 Common walls/ceilings (house & garage) air-sealed before insulation installed; house doors gasketed & closer installed o 	 	 o

 5.6 Exhaust fan (minimum 70 cfm, rated for continuous use) installed in garage & vented to outdoors (controls optional) o 	 	 o

 6.1 Certified low-formaldehyde pressed wood materials used (i.e., plywood, OSB, MDF, cabinetry) o 	 o

 6.2 Certified low-VOC or no-VOC interior paints & finishes used o 	 o

 6.3 Carpet, adhesives, & cushion qualify for CRI Green Label Plus or Green Label testing program o 	 o 	 o

 7.1 HVAC system & ductwork verified dry, clean, & properly installed o

 7.2 Home ventilated before occupancy OR initial ventilation instructions provided for buyer o 	 o

 7.3 Completed checklist & other required documentation provided for buyer o 	 o

Rater/Provider: Builder:

Company: Company: 

Signature: Signature: Moisture Control Combustion Pollutants Pests HVAC Final Radon Materials

CHAPTER 10 / BUILDING AMERICA BEST PRACTICES SERIES

10.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Guidance for Completing the Indoor airPLUS Verification Checklist:

1. Only ENERGY STAR qualified homes verified to comply with these specifications can earn the Indoor airPLUS label. See Indoor 

airPLUS Construction Specifications for full descriptions of the requirements, terms, exceptions, abbreviations, references, and 

climate map used in this checklist. Verification is not complete until this checklist is completed in full and signed.

2. Check one box per line. Check “N/A” for specifications that do not apply for specific conditions (e.g., climate) according to the

Exceptions described in the Indoor airPLUS Construction Specifications. Check either “Builder” or “Rater” for all other items 

to indicate who verified each item. Items may be verified visually on site during construction, by reviewing photographs taken 

during construction, by checking documentation, or through equivalent methods as appropriate. If using a performance testing 

alternative to meet requirement 4.2 or 4.4, the box marked “Tested” must be checked and testing documentation must be provided in the Home Energy Rating System/Builder Option Package (HERS/BOP) file.

3. The rater who conducted the verification, or a responsible party from the rater’s company, must sign the completed verification 

checklist. The builder must sign the checklist if any items in the “Builder” column are checked, and by so doing accepts full 

responsibility for verifying that those items meet Indoor airPLUS requirements.

4. The builder provides one copy of the completed and signed checklist for the buyer. The HERS/BOP provider or rater files a copy 

with HERS/BOP and ENERGY STAR documentation (e.g., Thermal Bypass Checklist) for the home. 

5. The checklist may be completed for a batch of homes using a RESNET-approved sampling protocol when qualifying homes as 

ENERGY STAR. For example, if the approved sampling protocol requires rating one in seven homes, then the checklist will be 

completed for the one home that was rated. 

Note: The Indoor airPLUS Construction Specifications are designed to help improve indoor air quality (IAQ) in new homes compared with homes built 

to minimum code. These measures alone cannot prevent all IAQ problems; occupant behavior is also important. For example, smoking indoors would 

negatively impact a home’s IAQ and the performance of the specified Indoor airPLUS measures.

 

Notes: 

For further information on the Indoor airPLUS program, visit epa.gov/indoorairplus.

All Indoor airPLUS qualified homes meet strict 

guidelines for energy efficiency set by ENERGY STAR, 

the nationally-recognized symbol for energy efficiency. 

Qualified homes earn the 

Indoor airPLUS label. 

Place it next to the 

ENERGY STAR label.

10.7

CHAPTER 10. OCCUPANT HEALTH AND SAFETY

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 10.7
Building America believes in real results. The only way to confirm 

results is to test for them. Therefore, in addition to required 

inspections by the code inspector, Building America recommends 

that site supervisors conduct systematic inspections during the 

course of construction, and that a formal commissioning be 

conducted before handing the keys to new homeowners. The 

steps described in this chapter will confirm your workmanship, 

giving you peace of mind while reducing the likelihood of costly 

callbacks. Some of the activities recommended here are now 

required by the 2009 IECC, as noted in green in this section. 

These commissioning steps can reduce callbacks and litigation 

risks for builders:

•	 Develop a commissioning plan appropriate to the home and 

the equipment installed.

•	 Test every house.

•	 Review commissioning results with installers.

•	 Provide the homeowner with information on the proper operation 

and maintenance of mechanical systems and other equipment. 

Walk-Throughs During Construction

General walk-throughs and inspections are especially good at 

critical times during construction before the next step makes 

it impossible to detect a problem or make a repair. Especially 

when energy-efficient systems-designed housing is new to your 

subcontractors, you should conduct multiple inspections to 

ensure that the subcontractors have understood what is required 

of them and how to implement it. After the process has become 

more routine, you might get by with spot inspections. HotSpot 

Chapter 11.

Inspecting, Testing, 

and Commissioning

CHAPTER TOPICS

11.1 Walkthroughs 

During Construction

11.2 Building Commissioning

Duct blaster testing confirms that 

ducts are well sealed (Photo source: NREL).

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inspections done by the site supervisor and pre-job/post-job 

checklists filled out by the subcontractor can help solve recurring 

problems. These are both described in Chapter 12. A checklist for 

designers in Chapter 13 contains many of the provisions that site 

supervisors should look for and work to include. 

Building Commissioning

Basic commissioning of the house and its mechanical systems is 

vital for high-performance housing and should be completed before 

the home is considered ready for the homeowner to take possession. 

Commissioning activities include verifying the installation and 

operation of HVAC equipment, especially for advanced systems 

like combination water/space heating systems, ground-source heat 

pumps, solar thermal systems, and photovoltaic arrays. Combustion 

safety testing should be conducted if any combustion appliances 

(including fireplaces) are installed. Additional testing recommended 

by Building America includes whole-house air leakage testing with 

a blower door test, duct air tightness testing, and pressure balance 

testing of each room. These activities are described below.

Pre-Dry Wall Inspection and Duct Pressure Testing

[The 2009 IECC 403.2 requires that ducts be tested for air tightness 

and allows for the testing to occur either before or after drywall is put 

up. If tested at pre-drywall or rough-in, they must be ≤ 6 cfm per 100 

ft2 of conditioned floor area at 25 Pa; if tested after construction, then 

≤ 8 cfm at 25 Pa. (If the air handler and all ducts are in conditioned 

space, duct leakage testing is not required.)] Building America 

recommends performing a duct pressure test (“duct blaster” 

test) before drywalling, with the HVAC contractor present. If 

the ductwork fails to meet the pressure criteria, a smoke test will 

reveal the worst leaks and they can be sealed while they are still 

accessible. The HVAC contractor should also test the HVAC 

system to ensure that thermostats and zone dampers are operating 

correctly and that bypass dampers are properly adjusted. The 

pre-drywall inspection is also a good time to ensure that insulation 

and draft-stopping have been properly installed. 

Whole-House Pressure Testing and HERS Rating 

After completion of the home, including all interior and exterior 

finishes but before occupancy, whole-house air tightness is tested.

[The 2009 IECC 402.4.2 gives two options for demonstrating building 

air tightness. The home can be blower door tested and must show 

“Monitoring progress is the 

only way you are going to 

change behavior.” 

Nat Hodgson, vice president of construction, 

Pulte Homes Las Vegas Division

Before the drywalling starts, you should 

conduct a pre-drywall inspection to 

test ducts and make sure insulation is 

properly installed and test moisture 

levels in framing.

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11.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
leakage of less than 7 air changes per hour at 50 Pa. Or, the 2009 IECC 

allows an extensive visual inspection of all of the areas listed in the 2009 

IECC 402.4.2.2.] Building America recommends a blower door test. 

Also, at this time, you should verify that all specified energy-efficient 

lighting and appliances were installed and check the air-conditioner 

or heat pump refrigerant charge if your HVAC contractor has not 

already done so.

Duct testing and whole-house pressure tests can be conducted by a 

certified HERS rater. The HERS rater should conduct a combustion 

safety test of all fuel-fired equipment as part of the rating certification. 

The HERS rating itself can be a valuable marketing tool for an 

energy-efficient house; a HERS score of 70 or lower can qualify a 

home for DOE’s Builders Challenge certification if other criteria are 

met (see Chapter 2 of this guide or www.builderschallenge.gov for 

more information).

To identify a certified rater in your area, check the registry at 

the Residential Energy Services Network (RESNET) website: 

www.natresnet.org.

SnapShot Form 

Building Science Corporation developed a commissioning checklist 

called the SNAPSHOT form. This form is shown on the next 

page and is available at www.buildingscience.com/documents/

reports/rr-0413-the-snapshot2014a-quick-description. Also, the 

Air Conditioning Contractors of America (ACCA) has developed 

guidance on commissioning of residential mechanical systems, 

HVAC Quality Installation Specification, ANSI/ACCA 5 QI-2007, 

which is available at www.acca.org/quality/. 

Homeowner Education 

Homeowners should also be given information on maintenance 

and operation of the HVAC equipment in their new home. 

Building Science Corporation put together a homeowner’s manual 

for the EcoVillage project in Cleveland, Ohio, that can serve as 

a sample for builders wishing to create a homeowner’s manual 

for their developments. The manual can be downloaded at 

www.buildingscience.com/documents/reports/rr-0310-ecovillagehomeowner-handbook.

For More Information on 

Inspecting, Testing, and 

Commissioning

Air Conditioning Contractors of America 

(ACCA) HVAC Quality Installation Specification – 

ANSI/ACCA 5 QI-2007, www.acca.org/quality/

Building Science Corporation. 2004. The 

“SNAPSHOT”- A Quick Description, Research 

Report 0413a, www.buildingscience.com/

documents/reports/rr-0413-the-snapshot2014aquick-description

Building Science Corporation. 2004. EcoVillage 

Homeowner Handbook, Research Report 0310, 

www.buildingscience.com/documents/reports/rr0310-ecovillage-homeowner-handbook

Building Science Corporation. 2008. Quality 

Assurance Roadmap for High Performance 

Residential Buildings, www.toolbase.org/PDF/

BestPractices/QualityAssuranceRoadmap.pdf

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11.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Getting a high-performance home requires having good plans; the 

proper contracts, permits, and materials; and properly trained and 

competent installers, who are scheduled at the right time and whose 

work is verified with testing. 

Construction and Contract Documents 

Builders should use construction and contract documents 

[in compliance with 2009 IECC 103] including plans and specifications, 

scopes of work, and job-ready and job-complete checklists, to 

describe and define exactly what you want from your subcontractors.

PLANS AND SPECIFICATIONS – Elevations, floor plans, and 

equipment layout should clearly identify all details related to 

energy efficiency, such as duct layout, advanced framing techniques, 

moisture management techniques, and air sealing details. Plans 

and specifications should include sufficient building and equipment 

details for the code inspector [as required by the 2009 IECC 103]. 

SCOPES OF WORK – Scopes of work define expectations and 

explain unfamiliar sequences of work. The Building America research 

teams have put together an extensive set of sample scopes of work, 

builders can include with contract documents, covering the foundation, 

framing, walls/drainage plane, windows, HVAC, and air sealing. See 

Appendix E of Achieving 30% Whole-House Energy Savings Level in 

Marine Climates. BAIHP et al. 2006, http://apps1.eere.energy.gov/

buildings/publications/pdfs/building_america/39743.pdf.

JOB-READY CHECKLIST – Signed by the site supervisor and trade 

contractor, the job-ready checklist includes all items that must be 

installed or prepared on the job site, by other trade contractors, 

before the contractor’s work can begin.

Chapter 12.

Construction Site 

Documents, Scheduling, 

and Training

CHAPTER TOPICS

12.1 Construction and 

Contract Documents

12.3 Scheduling

12.5 Training Installers

“It is one thing if you know what 

to do, but it is really the workers 

installing the products that need 

to understand how AND why. The 

quality of the installation is critical 

with energy-efficient construction; 

otherwise, it will not perform well 

and will defeat the purpose.”

David Hall, project manager, Shaw 

Construction, Junction City, Colorado

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JOB-COMPLETE CHECKLIST – Signed by the site supervisor 

and trade contractor, it confirms that the contractor’s work was 

completed as specified.

Site supervisors should review construction documents before 

they are folded into contracts and should continue to provide 

recommendations as these documents are put into practice to 

make them as effective as possible. The popular management term 

for ongoing feedback and dialogue is “continuous improvement,” 

a term coined by W. Edwards Deming. The point here is that when 

workers in the field find ways to improve designs or construction 

processes, that information needs to be communicated back to 

designers and managers so that documentation can capture those 

improvements. Although individual improvements may seem 

small, capturing these in construction documents helps you achieve 

superior building in the field. 

Contract Documents

Clear contract documents make for clear expectations with trade 

contractors. Ensure that trade contracts include the following 

provisions adapted from the NAHB Research Center Toolbase:

•	 Trade contractors are contractually obligated to ensure that 

workers fully understand field specifications and builder quality 

assurance processes using pre-job and post-job checklists.

•	 A competent crew leader will be in charge of all crews and be able 

to communicate with the builder’s site supervisor.

(left) Use plans to spell out details that 

will ensure energy efficiency and durability 

like framing techniques, duct layouts, 

housewrap, flashing, and air sealing.

(right) Hold a pre-construction meeting 

with all subcontractors present to talk 

about the schedule and trade interactions, 

especially any changes from the typical 

routine to accommodate new methods 

or technologies.

“We have every trade fill out jobready and job-complete forms. We 

want to know what was ready and 

what wasn’t when they showed up 

at their job. Those delays frustrate 

them and cost us money.”

Vern McKown, co-owner of Ideal Homes, 

in Norman, Oklahoma, shared these tips at 

the EEBA National Conference in Denver, 

Colorado, September 2009

“We work tightly with our trade 

contractors. They know our 

system and what we expect. When 

we started using ICFs in 2002 we 

had to do a lot of training. Now 

they understand.”

Fred Giacci, owner, Devoted Builders, 

Kennewick, WA

CHAPTER 12 / BUILDING AMERICA BEST PRACTICES SERIES

12.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
•	 All work must be completed in accordance with field specifications, 

applicable building codes, and industry standards.

•	 Trades must identify recurring errors in their work and train 

crews as needed to reduce similar errors (see HotSpots example 

in this chapter).

•	 Trades must self-inspect each phase of work before reporting the 

work complete to the site supervisor. Trades will confirm in writing 

that all materials and equipment were installed according to field 

specifications and manufacturers’ instructions, using pre-job and 

post-job checklists. 

•	 Copies of both field specifications and the manufacturers’ 

instructions should be available on the job site.

For More Information on Construction 

and Contract Documents

NAHBRC. 2006. “Quality Matters: Six Ways to Improve Trade Contracts.” ToolBase News, 

Summer 2006: Volume 11, Issue 3.

Scheduling

Building an energy-efficient home requires careful attention to 

scheduling. Several new construction techniques require changing 

the order of subcontractors or a shifting of responsibilities, and 

some new activities will need to be added into the schedule. Here are 

some important schedule considerations:

•	 Schedule HVAC rough-in before plumbing and electrical. It is far 

more important for the ductwork to have unconstricted access and 

pathways than it is for wires or pipes. However, be sure needs for 

other systems, such as drain pitch, are coordinated.

•	 If using an insulated, conditioned attic, schedule insulating under 

the roof deck before HVAC is installed. The insulators must be able 

to do their job without tromping on the carefully placed ductwork.

•	 Be sure to schedule caulking of electrical and plumbing 

penetrations before the drywall is completed and after the lines 

have been installed.

•	 Don’t forget to schedule for pipe insulation under the slab.

“Quadrant gives us a schedule and 

we know we can count on it. With 

most of our other builders, if they 

have a job they want us to start 

tomorrow, we need to stop by and 

make sure the work will be ready. 

With Quadrant, we don’t have to 

do that. They are predictable and 

reliable, and that is very nice from 

a trade standpoint.”

Wade Craig, manager of Bob’s Heating and 

Air Conditioning, the HVAC contractor for 

Quadrant Homes of Bellevue, Washington

Quadrant Homes, a Building America 

builder in Bellevue, Washington, builds 

its wall panels in a factory to ensure 

consistency and shorten site 

construction time.

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•	 Be sure to schedule pre-drywall insulation inspections, flashing 

inspections, and envelope and duct pressure tests. Inspect at key 

points to ensure that insulation and envelope sealing take place 

before areas become inaccessible. Inspections are much more likely 

to happen if scheduled, and subcontractors may be a bit more 

conscientious if they know their work will be evaluated. 

•	 If ducts are installed in conditioned space, drywall must be 

installed behind duct chases and soffits before they are framed.

Some situations that may require a shifting of responsibilities 

include the following:

•	 If using advanced framing techniques that include two-stud 

corners and floating drywall corners, someone must attach drywall 

clips. The framer is a more likely candidate than the drywall 

installer for framing modifications.

•	 Some caulking work needs to be done by the HVAC subcontractor. 

In particular, the main supply and return trunks that lead through 

the walls need to be caulked by the person connecting them to the 

equipment. Don’t let the drywall finisher do this with mud—it is 

neither a good sealant nor durable enough. Also, all duct terminations, 

including jump ducts, must be sealed when registers are installed.

•	 Some post-finish caulking can be avoided by having the electrician 

use pre-fabricated airtight electrical boxes. 

•	 If installations of windows and drainage planes are done by 

different subcontractors, the window installer must be careful 

to leave flashing unattached at the bottom so that the first row 

of building paper may be tucked under it (see Chapter 14 for an 

installer’s guide to window flashing, housewrap, and sealants).

•	 If you are using insulated headers, the framer will need to install 

insulation inside any double headers (using sandwiched foam 

insulation). Open headers may be left for the insulation contractor. 

Pre-fabricated, insulated headers are another alternative.

•	 Draftstops must be installed behind bathtubs and stairwells on 

exterior framed walls as well as attic knee walls. The framer or 

insulator should do this, but be sure that insulation is installed 

before the draftstopping material. The plumber can be asked to 

install the draftstopping and insulation.

Efficient scheduling of subcontractors can bring huge rewards in 

reduced costs and improved quality.

“You can expect what 

you inspect.”

Dr. W. Edwards Deming, the originator 

of total quality management

Make your expectations clear with onsite 

meetings and visible inspection checklists.

CHAPTER 12 / BUILDING AMERICA BEST PRACTICES SERIES

12.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Training Installers 

High-performance home construction does not just happen. Training 

is essential. Training need not involve days off the work site sitting 

in big lecture halls. Hands-on training is the most common approach 

and can happen constantly. Here are some ideas for training:

•	 Schedule a pre-construction meeting with all of your subcontractors 

present to review required interactions between trades.

•	 Meet with your subcontractors at the job site to explain how to 

use new techniques and materials. 

•	 Provide your contractors with manufacturers’ installation 

instructions and material data sheets and go through those 

instructions together. Other installation guides you may want to 

share with subcontractors include the field guides for installers 

shown in Chapter 14 of this guide, or the DOE Building Energy 

Code Program’s Code Notes (see examples in Appendix 2).

•	 Encourage in-house staff and regular subcontractors to take 

advantage of web-based videos, online training, and classroom 

training at community colleges during the off season.

Training Tips from Cold Climate Builders

Cold-climate builders who worked with Building America on 

demonstration projects (see case studies at the back of this guide), 

offered several recommendations for training. “Spend the time 

planning the work. Use proven technologies. Use subcontractors 

that understand and believe in this type of construction. Train your 

employees, especially the people doing the work in the field,” said 

David Hall, project manager for Shaw Construction, who built 

Burlingame Ranch Phase 1 for the City of Aspen, Colorado. “We 

held a project foreman seminar with Dr. Lstiburek at the beginning 

of the project and held several smaller training sessions at each 

“critical” construction phase with the subcontractor’s foreman 

and all employees that were onsite at the time. These training 

sessions covered window installation, installing perimeter flashing, 

setting doors, installing roofing materials, spray foam in walls, each 

mechanical, electrical and plumbing rough-in stage, installing the 

heat recovery ventilators, setting wall panels, etc.” Shaw produced 

one-page visual “training cards” in English and Spanish showing 

how to install particular components. Hall noted that the Builder’s 

Guide to Cold Climates (by Joe Lstiburek, published by EEBA) was 

also very useful. Shaw also conducted ongoing quality inspections 

with the field staff at each stage of construction.

Training on the job site can include 

reviewing manufacturers’ installation 

instructions, going through job-ready 

and job-complete checklists, and using 

HotSpot forms.

“We hold meetings with our trade 

contractor steering committee. 

We ask our employees and our 

subs, what can we do better? The 

construction supervisor walks 

the sites to identify any recurring 

issues. And we do NAHB quality 

certification audits of the whole 

company on a regular basis.”

Vern McKown, co-owner of Ideal Homes, 

in Norman, Oklahoma, shared these tips at 

the EEBA National Conference in Denver, 

Colorado, September 2009

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Building America’s team lead IBACOS took an active role in 

subcontractor training on the East Liberty project in Pittsburgh. 

IBACOS prepared mockups of field assemblies at its warehouse and 

provided hands-on training sessions. “We had the actual crew who 

would be performing the work in the field practice by working on 

the mockups. If they had any questions or suggestions for improving 

the process, we could work this out before we got into the field,” said 

Kevin Brozyna, an IBACOS building performance specialist.

Training Opportunities

Building America research partners provide training to the builders with 

whom they work. In addition, these Building America partners and 

building science organizations offer national training and certifications.

Certification Training

Two certifications are recognized nationally by practitioners of 

building energy efficiency: BPI (Building Performance Institute) and 

RESNET (Residential Energy Services Network). In addition, many 

states acknowledge Weatherization Inspector/Auditor certifications. 

The following websites provide information about training toward 

pursuing these certifications:

•	 The BPI website at www.bpi.org/affiliates.aspx provides a database 

search function for identifying approved courses at specific 

locations for upcoming training.

•	 The RESNET website at http://resnet.us/rater/map provides a 

U.S. map for identifying approved courses at specific locations for 

upcoming training.

•	 For specific state weatherization programs, Google the state name 

and the words “weatherization programs,” which should lead to 

a link for that state’s program with contact information, training 

requirements, and training resources.

•	 For online training, Saturn Resource Management at 

www.saturnonline.biz offers self-paced interactive courses for 

earning specific certifications.

Training Offered by Building America Partners

Building America team members and partners are among the most 

respected building scientists in the industry. These partners provide 

a variety of professional building science training courses, available 

at the links listed at the end of the chapter..

CHAPTER 12 / BUILDING AMERICA BEST PRACTICES SERIES

12.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
HotSpot Inspections and Training 

Systematically checking work is an important aspect of quality 

construction. The NAHB Research Center developed the concept 

of HotSpot Inspections and HotSpot Training. A “HotSpot” is 

a recurring issue that requires some form of remediation in order 

to get a site ready for the next trade or a home ready for move-in 

by a buyer. Builders can create their own HotSpot forms using the 

sample below.

Cooling the HotSpots

•	 Identify quality issues through 

job inspections, builder feedback, 

and comprehensive quality reviews. 

Include the problems that show 

up often on your punch lists time 

and again.

•	 Add HotSpot checkpoints to 

the inspection form where 

improvement is needed.

•	 Distribute and discuss HotSpot 

inspection forms in weekly 

production meetings.

•	 Train site supervisors in procedures 

to prevent identified problems. 

•	 Develop one-page diagrams that 

address specific problem areas 

and use these in toolbox talks to 

train crews.

•	 Monitor the use of the new 

processes and the quality of 

installations. HotSpot inspection 

forms are used by supervisors 

on every job. Results provide 

feedback on the effectiveness 

of the improvements.

•	 Celebrate success. When a 

HotSpot is no longer an issue, 

remove it from the HotSpot list 

and put it in a reminder section. 

In time, items may leave the 

inspection form altogether.

Adapted from the ToolBase Resources 

Website at www.toolbase.org/BestPractices/Business-Management/HotSpot-Inspections. This website includes 

examples of HotSpot inspection forms.

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Table 12.1. Training Opportunities

•	 Affordable Comfort at www.affordablecomfort.org/events_ceu.php?PageID=59

•	 Building Knowledge, Inc. at www.buildingknowledge.com/training/index.html

•	 Building Media Inc. at buildingmedia.com/education.html

•	 Building Science Corporation at www.buildingscienceseminars.com/

•	 ConSol at www.consol.ws/services/consulting/bect.php

•	 EcoBroker® International at www.ecobroker.com/eb/default.aspx

•	 Energy Center of Wisconsin at www.ecw.org/university/index.php

•	 Energy & Environmental Building Alliance (EEBA) at www.eeba.org

•	 Florida Solar Energy Center at www.fsec.ucf.edu/en/education/index.htm

•	 Gas Technology Institute at www.gastechnology.org/webroot/app/xn/xd.aspx?it=enweb&xd=3TrainingConfer/3_0TrainingHome.xml

•	 Green Building Alliance at www.gbapgh.org/content.aspx?ContentID=78

•	 Green Builder College at www.greenbuildercollege.com/

•	 Integrated Building and Construction Solutions (IBACOS) at www.ibacos.com/product-service/coaching-and-training-green

•	 Jay Hall and Associates at www.jayhall.com/services.htm

•	 Lutron Corporation at www.lutron.com/Education-Training/LCI/AboutLCI/Pages/About.aspx

•	 MaGrann Associates at www.magrann.com/engineering-consulting-services.html

•	 Manufactured Housing Institute at www.factorybuilthousing.com/educational_institute/

•	 The Midwest Energy Efficiency Alliance at www.mwalliance.org/programs/training-education

•	 National Association of Home Builders (NAHB) Research Center at www.nahbrc.com/builder/consultation/index.aspx

•	 National Communities Council at www.mhcommunities.org/cm/education/default.asp

•	 NeighborhoodWorks® America at www.nw.org/network/training/training.asp

•	 ONTILITY at www.ontility.com/training/solar-training-solar-education/about-ecotraining

•	 Partnership for Achieving Construction Excellence (PACE) at www.engr.psu.edu/pace/pace/dbia_boot_camp.aspx?p=40

•	 Potomack Group at www.potomack.net/iso-consulting.html

•	 Pratt Center for Community Development at www.prattcenter.net/contractor-training

•	 Sacramento Municipal Utilities District at www.smud.org/en/education-safety/Pages/index.aspx

•	 San Diego Gas & Electric www.sdge.com/business/rebatesincentives/training/workshops.shtml

•	 Schneider Electric at www.schneider-electric.com/sites/corporate/en/products-services/training/training.page

•	 Steve Easley and Associates at www.buildingmedia.com/steve.html

•	 Steven Winter Associates, Inc. at www.swinter.com/training/

•	 Southface Energy Institute at www.southface.org/learning-center/trainings/

•	 TexEnergy Solutions at www.texenergy.org/training.php

•	 University of Florida’s Program for Resource Efficient Communities at www.prattcenter.net/contractor-training

•	 Verified Green at www.verifiedgreen.org/course-offerings.html

•	 Washington State University Energy Extension Program at www.energy.wsu.edu/apps/training.aspx

CHAPTER 12 / BUILDING AMERICA BEST PRACTICES SERIES

12.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
This checklist summarizes the measures presented in Chapters 6–12. 

Designers, use this checklist as a reminder to investigate these 

measures throughout the design process. It is important to develop 

specifications and drawings to ensure that selected features are 

included in construction documents. 

This list can aid site supervisors by providing a master list of 

recommended home features. Use this list to develop customized onsite 

pre-job and post-job inspection checklists for each trade contractor.

Chapter 13.

Durability and Energy 

Efficiency Checklist

CHAPTER TOPICS

13.1 Foundation Assemblies

13.4 Wall Assemblies

13.6 Roof Assemblies

13.7 Whole-House Air Leakage

13.8 Mechanical Systems

13.11 Commissioning

Foundation Assemblies

Slab, crawlspace, and basement foundation types are all common in 

the cold climate. The checklists below address control of moisture, 

airflow, and heat flow in each foundation type.

Controlling Moisture in All Foundation Types

 Maintain a surface grade of at least a 6-inch drop for at 

least 10 feet around and away from the entire structure 

[2009 IRC R401.3].

 Drain impervious surfaces such as driveways, garage slabs, 

patios, stoops, and walkways away from the structure at ≥ 2% 

drop within 10 feet of the building [2009 IRC R401.3]. 

 Specify and show in details that 6-mil polyethylene sheeting or 

rigid foam insulation is to be placed directly beneath the slab 

or basement floor. The sheeting should continuously wrap the 

slab as well as footings up to grade [2009 IRC R406.3.2]. 

13.1

CHAPTER 13. CHECKLIST

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 13.1
 Damp proof all below-grade portions of the exterior foundation [2009 IRC R406]. Damp proof the 

exposed portion of the foundation with latex paint or other sealant. 

 Specify that footings poured independent of slabs or foundation walls are to be treated with a 

bituminous damp-proof coating of masonry capillary-break paint, or a layer of 6-mil polyethylene 

plastic to isolate the footing from the remainder of the assembly.

 Ensure that the lowest excavated site foundation level is above the local groundwater table at its 

maximum elevation [2009 IRC R408.6]. 

 Place a 4-inch-deep, 3⁄4-inch gravel bed directly beneath the polyethylene sheeting to act as a capillary 

break and drainage pad. 

 Do not place a sand layer between the vapor retarder and the concrete slab or basement floor. 

Differential drying and cracking is better handled with a low water-to-concrete ratio and wetted burlap 

covering during initial curing.

Controlling Moisture in Crawlspace and Basement Foundations

 Install a perimeter drain below the drainage plane along (not on top of) footings for all basements 

and crawlspaces where the floor is below grade (use perforated PVC pipe covered with gravel, 

landscape fabric, and backfill). 

 In all crawlspaces, install 6-mil polyethylene across the entire ground surface. Overlay all seams by 

12 inches and tape. Seal the polyethylene at least 6 inches up the walls or to a height equal to 

ground level.

Controlling Air Infiltration in All Foundation Types

 The foundation details should indicate that a sill gasket be installed between the foundation and 

the bottom plate of the exterior framed wall. This gasket also serves as a capillary break.

Controlling Heat Flow in Slab Foundations

 Slabs may be insulated at the perimeter with borate-treated foam board or rigid fiberglass insulation. 

Use only insulation approved for below-grade use. [R-Values are specified in 2009 IECC Table 402.1.1]

 Exterior insulation should be applied from the top of the foundation wall to the bottom of the frost 

line. Cover the exterior face of the insulation exposed to outside air using flashing, fiber cement board, 

parging, treated plywood, or membrane material. [R-Values are specified in 2009 IECC Table 402.1.1]

CHAPTER 13 / BUILDING AMERICA BEST PRACTICES SERIES

13.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Controlling Heat Flow in Crawlspace Foundations

 The preferred approach is to install insulation on the exterior side of the foundation wall. Products 

such as borate-treated foam board or rigid fiberglass insulation work well. Insulate the exterior side of 

the beam to R-5.6 [2009 IRC 403.3].

 Insulation that is exposed above grade must be covered with a protective coating such as flashing, 

fiber cement board, parging, treated plywood, or membrane material. 

 If insulation is placed on the interior, it must extend down the wall to a depth at least 2 feet below 

grade level and be rated for crawlspace and basement exposure.

 If the floor is insulated instead, insulate to R-30 in IECC climate zones 5 and 6, R-38 in climate zones 7 

and 8 (or sufficient to fill the framing cavity, at least R-19) [2009 IECC 402].

Controlling Heat Flow in Basement Foundations

 Wall insulating in basements is similar to the approaches described for crawlspaces. Basement floors are 

insulated similarly to slabs. [2009 IECC 402 requires R-10 rigid foam on the interior or exterior surface of 

the walls or R-13 cavity insulation on interior basement walls in IECC climate zone 5. In IECC climate zones 6, 

7, and 8, the requirement is R-15 continuous rigid foam insulated sheathing on the interior or exterior, or R-19 

interior cavity, or R-5 exterior plus R-13 cavity insulation. In IECC climate zone 5, R-10 slab floor edge insulation 

is required extending 2 feet horizontally under the slab or out from the building. In IECC zones 6, 7, and 8, this 

increases to R-15 and 4 feet.]

 Exterior wall insulation is preferable in basement foundation applications.

 Material in contact with the foundation wall and the concrete slab must be moisture tolerant. A capillary 

break must be placed between materials that transport moisture and moisture-sensitive materials.

 Interior insulation, if used, should employ one of the following methods:

 Use foil-faced polyisocyanurate rigid insulation attached directly to the above-grade portion of the 

wall. Extruded or expanded polystyrene can be attached to the below-grade portion of the wall. The 

polystyrene would require a gypsum board or equivalent covering. Foam sill seal or foam board can 

be used between the bottom plate of the wall and the concrete floor to provide a capillary break.

 Use either expanded or extruded polystyrene foam board attached to the entire foundation wall. 

Additional insulation can be added to a frame wall built on the interior of the foam insulation. If 

no frame wall with additional insulation is added, wood furring strips can be attached over the foam 

and gypsum board attached to the furring strips.

 Use pre-cast concrete foundation walls that come with a minimum of 1 inch of rigid foam insulation 

attached to the interior.

13.3

CHAPTER 13. CHECKLIST

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 13.3
Other Foundation Issues

RADON CONTROL

 Use a layer of gravel under the slab to provide a path for radon and other soil gas to escape to the 

atmosphere rather than being drawn into the house. 

 Use a vapor retarder to block soil gas entry into the house. 

 See EPA website: www.epa.gov/iaq/whereyoulive.html for information about local variations in 

radon levels. [Also see radon map and radon control recommendations in the 2009 IRC Appendix F.]

 Include a sub-slab-to-roof vent system to vent radon and soil gases.

 Include an active radon reduction system with fan if your homes are built in zone 1 

(high radon potential).

PEST CONTROL 

 Use local code and Termite Infestation Probability (TIP) maps to determine environmentally 

appropriate termite treatments, bait systems, and treated building materials for assemblies that 

are near soil or have ground contact [2009 IRC R318.1.].

 Provide roof drainage to carry water at least 3 feet away from the building.

 Apply decorative ground cover no more than 2 inches deep within 18 inches of the foundation.

 Keep plantings at least 18 inches from the foundation with supporting irrigation directed away from 

the finished structure.

 Specify and install an environmentally appropriate soil treatment and a material treatment 

(treated wood, termite blocks) for wood materials near grade. 

 Install a metal termite shield at the sill plate [2009 IRC R318.3].

Wall Assemblies

Controlling Liquid Water in Wall Assemblies

 Install flashing at all intersections of the wall with roofs and other building elements.

 Properly flash and seal windows, doors, and other penetrations through the wall.

 Specify and show in elevations building paper, housewrap [2009 IRC R703.2], or taped insulating 

sheathing (rigid foam insulation) behind the exterior cladding to serve as a drainage plane. 

 In walls with brick facades, provide an airspace between the brick and the drainage plane.

 For the drainage plane behind stucco cladding, include insulating sheathing and two layers of building 

paper or housewrap to avoid chemically contaminating the housewrap.

CHAPTER 13 / BUILDING AMERICA BEST PRACTICES SERIES

13.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
 If building paper is used as a drainage plane in areas prone to severe storms, use two layers to increase 

resistance to leakage at fasteners and to allow for more flexible installation.

 Overlap housewrap seams shingle style and tape seams. Properly lap at window flashing (over the 

flashing above the windows and to the side, and under the flashing beneath the window).

 Run housewrap top and bottom edges past top and bottom plates by at least one inch and seal at the edges.

 Use overhangs to keep water away from walls and penetrations and to provide shade.

Controlling Water Vapor in Wall Assemblies

 Back-prime wood and fiber cement cladding to avoid water saturation and migration.

 Do not install vapor barrier (e.g., polyethylene sheeting, foil-faced batt insulation, reflective radiantbarrier foil insulation) on the interior side of walls in air-conditioned structures. Wall assemblies should 

be able to dry to at least one side and in many cases both sides of the assembly.

 Do not use impermeable coverings, such as vinyl wallpaper, on exterior walls.

 Indicate on plans the methods, materials, and locations where sealing is needed to form the house-air 

pressure barrier. Specify the approach to be taken to meet vapor barrier code requirements.

 Use a Class 3 vapor retarder (latex paint) on interior side of walls with vented cladding over wall 

sheathing [2009 IRC 601.3].

 Leave a drainage space of at least 1/16-inch behind lap siding and 3⁄4 inch between stucco and plastic 

housewraps to control liquid phase water penetration. A 1-inch air gap is needed behind brick veneer

[as required by 2009 IRC R703.7.4.2].

Controlling Air Infiltration in Wall Assemblies

 Use interior gypsum board as the interior air infiltration barrier. Tape and mud gypsum board at 

all joints and the intersections of the wall with the floor and the ceiling [2009 IECC 402.4].

 Create an exterior air infiltration barrier using taped and sealed exterior rigid foam insulating 

sheathing to control wind washing and to keep air from entering the wall from the exterior. 

 Use the ENERGY STAR Thermal Bypass Checklist.

 Install insulation and draftstopping between bathtubs, dropped ceilings, dropped soffits, and 

stairwells on exterior walls.

 Seal all exterior wall penetrations (exterior lights, phone lines, vents, faucet pipes, cables, etc...) 

with caulk, gaskets, or other sealants.

 For occupant health and safety, verify sealing at all shared walls and ceilings between attached 

garages and living spaces. 

 For homes with attached garages, block and seal any gaps at joists spanning both conditioned 

space and the garage.

13.5

CHAPTER 13. CHECKLIST

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 13.5
Controlling Heat Flow in Wall Assemblies

 Use 2x6 advanced framing techniques and specify framing details in plans.

 Insulate wall cavities that separate conditioned and unconditioned spaces with high-density, unfaced 

fiberglass batts, spray-applied cellulose, or spray-applied foam. [The 2009 IECC 402 requires a wall R 

value of R-20 for wood-framed walls (or R-13 cavity plus R-5 insulated sheathing) for IECC climate zones 5 

and 6 and R-21 for IECC climate zones 7 and 8. For mass walls (concrete block, concrete, ICF, brick, etc.), the 

requirement is R-13 for exterior insulation or R-17 if more than half the insulation is on the interior in zone 5. 

The requirements are R-15/19 for IECC climate zone 6 and R-19/21 for IECC climate zones 7 and 8.] 

 Properly install wall insulation to ensure the cavity is completely free of voids.

 Use spray foam to insulate and seal rim joists (and where the wall connects to the roof in non-vented attics).

 Install taped rigid foam insulating sheathing (in addition to cavity insulation) on the exterior side of the 

wall to control heat, moisture, and air infiltration. 

 Install efficient windows with maximum U-values of 0.3 [2009 IECC Table 402.1.3 requires ≤ 0.35 U-value].

 Use ENERGY STAR-labeled doors.

 Use roof overhangs to provide shade and protect windows, doors, and walls.

Roof Assemblies 

Controlling Liquid Water in Roof Assemblies

 In areas with potentially high winds and heavy rains, apply 4-inch to 6-inch “peel and seal” self-adhering 

water-proofing strips over joints in roof decking before installing the roof underlayment and cover.

 Install roofing materials shingle-fashion to provide a continuous drainage plane over the entire surface 

of the roof.

 Properly flash roof valleys and edges and use kick-out flashing where roof edges abut walls. 

 Size gutters and downspouts to accommodate anticipated storms. Roof drainage should carry water at 

least 3 feet from the building.

Controlling Water Vapor in Roof Assemblies

 Install roof, ridge, and soffit ventilation in vented attics.

 Do not use any kind of interior vapor barrier material in the ceiling (e.g., polyethylene sheeting).

CHAPTER 13 / BUILDING AMERICA BEST PRACTICES SERIES

13.6 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Controlling Air Flow in Roof Assemblies

 Tape and seal all ceiling gypsum board seams so that the gypsum board functions as an air barrier. 

Ensure an air seal at the intersection between the walls and ceilings in attics, cathedral ceilings, 

and knee walls. 

 Use spray foam for tight sealing of the wall-roof intersection in non-vented attics. 

 Caulk all intersections of ceiling with other components (soffits, ceiling fans, duct registers, 

light fixtures, etc.) [2009 IECC 402.4]. 

 Use draftstopping in dropped ceiling areas.

 Use ceiling light fixtures that are rated for insulation contact and airtight (ICAT); 

install with proper trim and caulk cracks around light fixtures.

 Air seal all penetrations through top plates.

 Weatherstrip and insulate attic access hatches or doors.

 Seal all penetrations through the ceiling and the roof, including holes for flue stacks, wiring, fans, etc.

Controlling Heat Flow in Roof Assemblies

 Consider a non-vented attic.

 Install blown-in insulation at the appropriate depth on the top surface of ceiling gypsum board. 

[The 2009 IECC Table 402.1.1 requires a ceiling R value of R-38 in IECC climate zone 5 and R-49 in IECC 

zones 6, 7, and 8. A minimum of R-30 is required in cathedral ceilings, but this is limited to 500 ft2 or 20% of 

total insulated ceiling area, whichever is less (2009 IECC 402.2.2.)] Maintain the ceiling insulation level 

throughout the entire plane of the ceiling and over the top of the perimeter walls. A depth gauge should 

be visible from the attic hatch. 

 Use raised-heel energy trusses to maintain the thickness of ceiling insulation directly above the top 

plates of the exterior wall framing. [If raised heel trusses are used allowing full height of insulation over the 

wall top plate, then R-30 is permitted instead of R-38 in IECC zone 5 and R-38 is permitted instead of R-49 in 

zones 6, 7, and 8.]

 In vented attics, install baffles to prevent blocking of soffit vents and wind washing (when thermal 

insulation is blown back from the edges of the attic by wind blowing through the soffit vents).

Whole-House Air Leakage 

 Have building envelope tested for air leakage by a HERS rater who uses a blower door test. 

[The 2009 IECC 402.4.2 requires that whole house air tightness be demonstrated by a blower door test 

or extensive visual inspection. If the home is blower door tested air leakage must be less than 7 air changes 

per hour at 50 Pa.]

13.7

CHAPTER 13. CHECKLIST

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 13.7
Mechanical Systems 

Heating and Cooling Equipment 

 Size heating and cooling equipment using ACCA Manual J [2009 IECC 403.6].

 Specify central air conditioners at a minimum 13 SEER (10 EER) for cooling, and specify heat 

pumps at a minimum of 7.7 HSPF for heating.

 Install ENERGY STAR-qualified equipment.

 Install sealed combustion gas furnaces in conditioned space.

 Install HVAC equipment equipped with brushless, permanent magnet, direct-current motors.

 Isolate HVAC system and ducts from areas with potential pollutants including garage spaces.

 Have the refrigerant charge on the air conditioner or heat pump verified in writing by the installer to be 

within design specifications, using the superheat method for non-Thermostatic Expansion Valve (TXV) 

systems or the subcooling method for TXV systems. 

 Filter HVAC return air through a 4-inch standard filter or a Minimum Efficiency Reporting Values 

(MERV) 8 normal-thickness filter. Make the filter easy to access for cleaning or replacement and 

design the filter slot so there is no air bypass around the filter when the HVAC system is operating. The 

maximum air velocity through the filter should not exceed 400 fpm. [ASHRAE 62.2-2010 6.7 recommends 

MERV 6 or better.]

 Keep pressurization balanced from room to room by providing individual ducted returns for each 

room or by providing jump ducts or transfer grilles located in the walls of each room. Use flex duct 

and staggered grille locations or ducts lined with sound-absorbent material to minimize sound transfer 

through jump ducts.

 Consider alternative energy-efficient equipment such as variable refrigerant flow, mini-split ductless heat 

pumps or geothermal heat pumps.

Ducts

 Specify location, size, and type of ducts and registers on construction plans. Include heating and cooling 

ducts, passive return air ducts or transfers, location of the mechanical ventilation air inlet, and the 

locations of all exhaust outlets. Indicate the location of dedicated chases for ductwork.

 Place ducts and air handlers in conditioned space when possible. 

 Size ducts using ACCA Manual D [2009 IRC M1601.1]. 

 Keep duct runs as short as possible. Consider using a central duct chase in a dropped hallway ceiling 

with registers located along it providing air directly to rooms along the hallway.

 Use ducts made of galvanized sheet metal, duct board, or flex duct.

CHAPTER 13 / BUILDING AMERICA BEST PRACTICES SERIES

13.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
 Air seal insulated ducts running outside conditioned spaces, by use of proper duct-sealing techniques. 

Use these duct-sealing materials:

 For metal ducts: UL 181 mastic.

 For duct board: UL 181 tapes. 

 For flex duct: a combination of UL 181 mastic and strap ties. 

 Seal drywall connections to ducts with caulk or foam sealant.

 Insulate ducts in unconditioned spaces. Insulate supply ducts to R-8 minimum and return 

ducts to R-4 minimum.

 Insulate ducts in conditioned space to R-8 for supply and R-4 for return ducts to avoid 

condensation formation.

 Equip each bedroom with a separate return duct, transfer grille, or jump duct.

 Don’t use “pan ducts” (spaces between joists and in stud cavities) as supply or return air ducts 

[2009 IECC 403.2.3].

 Don’t locate ducts in exterior walls.

 Seal any return-air ductwork or air handler located in the garage with UL 181-approved mastic.

 Don’t put the air handler in the garage unless it is in an air-sealed, insulated closet. Ducts located in the 

garage may not have any openings in the garage [2009 IRC R302.5.2] and furnaces and air handlers that 

supply air to living spaces shall not supply air to or return air from a garage [2009 IRC M1601.6]. The air 

handler and any return-air ductwork should be thoroughly sealed with UL 181B-M-compliant mastic, 

with a target leakage between the duct system and the garage of 0 CFM @ 25 Pa.

 Verify duct air tightness with a duct blaster pressure test. Test at rough-in when leaks can be easily accessed 

and sealed. [The 2009 IECC 403.2 requires that ducts be tested for air tightness and allows for the testing to 

occur either before drywall is put up or after drywall is put up. If tested at pre-drywall or rough-in, they must be 

≤ 6 cfm per 100 ft2 of conditioned floor area at 25 Pa; if tested after construction, than ≤ 8 cfm at 25 Pa. (If the 

airhandler and all ducts are in conditioned space, duct leakage testing is not required by the 2009 IECC but is 

recommended by Building America to ensure ducts are properly connected and that air flow is balanced].

Ventilation

 Install whole-house mechanical ventilation compliant with ASHRAE Standard 62.2. 

 Provide a fresh-air intake ducted to the return air side of the air handler to provide fresh air and air 

pressure balancing for homes ventilated primarily with exhaust-only kitchen and bath fans.

 Filter ventilation air through a 4-inch standard filter or a new MERV 8 normal-thickness filter. Make 

the filter easy to access for cleaning or replacement and design the filter slot so there is no air bypass 

around the filter when the HVAC system is operating.

 Install ENERGY STAR-qualified low-sone exhaust fans in bathrooms and kitchens. Sone ratings 

should not exceed 1.5. 

13.9

CHAPTER 13. CHECKLIST

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 13.9
 Seal bathroom and kitchen fans to drywall with caulk or gaskets.

 Equip outdoor air intakes and exhausts with automatic or gravity dampers that close when the 

ventilation system is not in operation [2009 IECC 403.5].

 Consider installing a night ventilation cooling system in appropriate subclimates.

Plumbing

 Locate bathrooms and other hot water-consuming activities near each other in house layout. 

 Centrally locate the water heater to minimize piping trunk lengths. 

 Bury plumbing in attic insulation for single-story, slab-on-grade homes and in interstitial space 

between floors for multi-story homes.

 Install code-permitted or manufacturer-approved minimum size lines.

 Insulate hot water supply lines to R-4. [2009 IECC 403.3 requires R-3 minimum.]

 Insulate tanks to at least R-12.

 Use a central manifold (home-run) water distribution system.

 Use PEX (high-density polyethylene) piping. Use approved connectors so PEX pipes are not connected 

directly to water heaters or solar collectors.

 Do not install continuous recirculation pumping systems on hot water lines. Use an on-demand switch if 

recirculation controls are desired to minimize the energy penalty of a circulation system.

 Use gas-fired instantaneous power-vented or direct-vented water heaters inside conditioned space.

 Consider alternative technologies like on-demand gas or electric water heaters, solar thermal water 

heaters, and ground-source heat pumps for water heating. If using solar-thermal water heating, use 

systems with freeze protection. 

 Use unglazed solar pool water heaters on spas and swimming pools in the cold and very cold climates, 

and use two-speed pool filter pumps and controls to reduce energy.

Electrical

 Use ENERGY STAR-qualified compact fluorescent lights (CFLs) in all fixtures expected to be on more 

than 2 hours per day. [The 2009 IECC 404 requires that at least 50% of the lamps in permanently installed 

lighting fixtures be high-efficacy lamps.]

 Use recessed ceiling lights that are ICAT rated (approved for insulation contact and airtight) [2009 IECC 402.4.5].

 Use occupant sensors, photocells, and motion sensors to automate lighting operation.

 Use air-sealed electrical boxes in all exterior walls and ceilings adjacent to unconditioned attics.

 Use ENERGY STAR-qualified appliances.

CHAPTER 13 / BUILDING AMERICA BEST PRACTICES SERIES

13.10 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Occupant Health and Safety

 Use only sealed combustion or power-vented combustion appliances in conditioned space.

 Direct vent gas cooking ranges to the outside [2009 IRC M1503.4].

 Do not use combustion appliances that rely on passive combustion air supply openings or 

outdoor supply air ducts that are not directly connected to the appliance.

 Use sealed-combustion gas fireplaces to eliminate the threat of harmful combustion gases 

entering the house. 

 Install CO detectors and smoke alarms [NFPA 720 and NFPA 101 24.3.4.1].

 Use filtration systems for forced air systems that provide a minimum atmospheric dust spot 

efficiency of 30% or MERV 8 or higher.

 Maintain indoor humidity in the range of 30% to 60% by controlled mechanical ventilation, 

mechanical cooling, or dehumidification. 

 Install carbon monoxide detectors (hard-wired units, one approximately every 1,000 square feet) 

in any house containing combustion appliances and/or an attached garage.

 Maximize hard surface areas (tile, vinyl, hardwood) to enable homeowners to better manage dust 

for health purposes. For slab-on-grade houses, this also reduces cooling loads.

 Provide occupants with information about the safe, healthy operation and maintenance of the 

building systems that provide space conditioning, hot water, and lighting.

 Ventilate attached garages with a 100 cfm (ducted) or 80 cfm (un-ducted) exhaust fan, venting to 

outdoors and designed for continuous operation. Or, install automatic fan controls that activate 

the fan whenever the garage is occupied and for at least 1 hour after the garage is vacated.

 Completely seal the garage from the conditioned areas of the house to keep car exhaust and 

chemical fumes from entering the home [2009 IECC 402.4.1 and ASHRAE 62.2-2010, 6.5.1].

 Vent clothes dryers and central vacuum cleaners directly outdoors [2009 IRC M1502.4.1].

 Use low-VOC paints, finishes, varnishes, and adhesives whenever possible.

Commissioning

 Test ducts for air leakage at rough-in. [Per 2009 IECC 403.2, at rough-in, duct leakage to the outdoors 

should be ≤ 6 cfm/100ft2 of conditioned floor area at 25 Pa.]

 Test whole-house air leakage with a blower door. [Per 2009 IECC 402.4.1, blower door air leakage 

results should be ≤ 7 ACH @ 50 Pa.]

 Do combustion safety testing.

 Provide homeowners with operation and maintenance guidance to HVAC and mechanical systems.

13.11

CHAPTER 13. CHECKLIST

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 13.11
Chapter 14.

Field Guides 

for Installers

On the following pages you will find step-by-step, easy-to-follow 

illustrated instructions for implementing key energy-efficiency 

technologies.

These guides are designed to be easily duplicated and distributed. 

Hand them to your subcontractors when you meet with them at the 

job site, to help them understand what you expect.

•	 Advanced Framing

•	 Foundation System, Insulation, Moisture and Air Leakage Control

•	 Masonry Construction

•	 Housewrap

•	 Window Flashing

•	 Wall-to-Roof Flashing

•	 Interior Air Sealing

•	 Exterior Air Sealing with Insulating Sheathing Panels

•	 Plumbing Air Sealing

•	 Electrical Air Sealing

•	 Installing Fiberglass Batt Insulation

•	 Installing Windows in Walls with External Rigid Foam Insulation

•	 Duct Location

•	 Air Handler and Duct Sealing 

•	 Ductless Heat Pump Installers Guide 

(from Northwest Energy Efficiency Alliance www.ductless.com)

•	 Ice Dam Prevention

14.1

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.1
Advanced Framing

The following tips show examples of framing techniques that can create more open space to hold 

insulation while reducing framing costs and waste. The following page shows an example of a 

detailed framing plan. Such detailed plans should be included in construction documents.

Size headers for actual 

loading conditions: 

Non-load-bearing walls 

do not need structural 

headers. Proper 

sizing may allow for the 

use of insulated headers 

in which foam 

insulation is 

sandwiched 

between 

sheathing.

Use two-stud corners:

Rather than using a third 

stud as a nailing edge for 

interior gypsum board, use 

drywall clips, a 1x nailer 

strip, or a recycled plastic 

nailing strip. Using drywall 

clips also reduces drywall 

cracking and nail popping.

Eliminate redundant floor 

joists: Double floor joists 

aren’t needed below nonload-bearing partitions. 

Partitions parallel to 

overhead floor or roof 

framing can be attached to 

2x3 or 2x4 blocking. Nailing 

directly to the sub-floor 

provides adequate support.

Use 2x3s for 

partitions:

Interior, non-loadbearing partition 

walls can be framed 

with 2x3s at 24-in. 

on center or 2x4 

“flat studs” at 16-in. 

on center. 

24” 24” 24” 24” 24”

24”

24”

24”

24”

24”

24” 24” 24” 24” 24”

24”

24”

24”

24”

24”

24” 24” 24” 24” 24”

24”

24”

24”

24”

24”

24” 24” 24” 24” 24”

24”

24”

24”

24”

24”

24” 24” 24” 24” 24”

24”

24”

24”

24”

24”

24” 24” 24” 24” 24”

24”

24”

24”

24”

24”

FROM 

ABOVE

Two-Foot Module Design:

Starting with the foundation, the house 

footprint should be based on 2-foot 

increments. Layouts should be based on 

this 2-foot grid to minimize material waste.

Frame 24-in. on center:

24-in. on center studs are structurally 

adequate for most residential applications. 

Even when the stud size must be increased 

from 2x4 to 2x6, 24-in. spacing can 

significantly reduce framing lumber needed. 

Ladder-block exterior wall 

intersections: Partitions can be 

nailed either directly to a single 

exterior wall stud or to flat blocks 

inserted between studs.

Align framing members and use a single top 

plate: Plate sections are cleated together using 

metal flat plate connectors. Metal connectors can 

be used at partition wall intersection. Underside 

blocking is another option for single top plate butt 

joints. For multistory homes, this may increase 

the stud size on lower floors to 2x6.

Exterior wall top plate

Interior wall 

top plate

Metal connector plate

14.3

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.3
Detailed Wall Framing Layout

Use detailed layouts like this to make sure studs align from first floor to second floor to roof and design on a 24-inch grid.

Figures courtesy of the 

NAHBRC and prepared 

by Steve Baczek.

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Wall Design for Seismic Regions

This advanced framing wall panel for seismic regions was designed and tested by Building Science Corporation and the U.S. Army 

Construction Engineering Research Laboratory (CERL) with funding from DOE’s Building America program. The panel was designed 

to provide lateral capacity that is as good as or better than traditional plywood-sheathed shear panels, while not interfering with the 

installation of insulation sheathing directly to the framing members. It has an allowable design capacity of 650 lb/ft or 2,600 lb per panel.

(Figure Source: Building Science Corporation)

Sources and Additional Information

Building Science Corporation. 2009. Enclosures That Work - Building Profile: Hot-Dry/Mixed-Dry: Sacramento, 2009, 

www.buildingscience.com/documents/profiles/etw-sacramento-profile/#F11

NAHB Research Center. “Advanced Framing Techniques: Optimum Value Engineering (OVE),” Available at www.toolbase.org/Construction-Methods/

Wood-Framing/advance-framing-techniques accessed 6-4-08

14.5

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.5
Foundation System, Insulation, Moisture and Air Leakage Control

= Sealant or Gasket

Concrete

slab

Seal all slab

penetrations

Concrete footing below frost depth

INTERIOR INSULATION 

FOR FLOATING SLAB

EXTERIOR INSULATION

PACKAGE

Gravel base

(4-6" deep coarse, no fines)

Perforated

drain pipe

Hold drywall 

1/2” above floor

Polyethylene or damp proofing capillary break

Polyethylene vapor diffusion retarder

Perforated drainage 

pipe embedded 

in gravel

Use extruded (R-5 per inch)

or expanded (R-4 per inch)

polystyrene or rigid

fiberglass insulation

Cover insulation 

exposed above grade

(see list on reverse)

Rigid foam insulation

(extends under entire slab

and replaces polyethylene 

vapor retarder)

Radon reduction

3" plastic pipe vent stack

Optional blower

Sill gasket 

membrane

(also serves as 

capillary break)

Metal termite 

flashing

Damp proofing Damp proofing

Roof flashing

SHALLOW FROST-PROTECTED 

FOUNDATION

(get code approval before proceeding)

6 Mil. Polyethylene

vapor diffusion retarder

(extends under grade beam 

acting as a capillary break)

Rigid insulation 

extends horizontally

(horizontal distance

equivalent to frost depth)

Rigid insulation 

extends horizontally 2’

Damp proofing

Cover insulation 

exposed above grade

(see list on reverse)

See more information on the following page.

14.7

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.7
Figure Source: Building Science Corporation

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.8 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Figure Source: Building Science Corporation

14.9

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.9
Figure Source: Building Science Corporation

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.10 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Sources & Additional Information

U.S. DOE, Technology Fact Sheet on Slab Insulation.

U.S. EPA, Building Radon Out: A Step-By-Step Guide oni How to Build Radon Resistent Homes.

Southface Energy Institute. Fact Sheets #29: Insulating Foundation and Doors.

Southface Energy Institute. Fact Sheets #30: Radon-Resistant Construction for Builders.

www.southface.org/home/sfpubs/techshts/30_radonresistantconst.pdf

Building Science Consortium. Introduction to Building Systems Performance: Houses that Work II. 

•	 Keep all untreated wood materials away 

from contact with earth and concrete. 

•	 Design the house structure with 

overhangs, gutters, drainage planes, 

and flashing to shed rainwater and 

conduct it away from the house.

•	 Slope the earth away from the house 

and ensure that no irrigation strikes 

near the foundation.

•	 Use a sill gasket for air sealing.

•	 Install a protective shield such as 

metal flashing, plastic L bracket, or 

a membrane (such as EPDM flexible 

roofing material*) to block capillary 

water wicking into the wall from the 

foundation. The protective shield may 

also serve as a termite shield.

•	 Slabs require a foundation drain where 

the slab (or floor) is located below 

grade. Install a foundation drain 

alongside the footing (not above it). 

The drain should rest in a bed of coarse 

gravel (no fines) that slopes away from 

the foundation and is covered with 

filter fabric.

•	 Exterior rigid fiberglass insulation 

may provide a drainage plane that will 

channel water to the foundation drain 

and relieve hydrostatic pressure. 

•	 Exterior foundation wall insulation 

requires a protective coating at 

above-grade applications. Examples 

of protective coverings for exterior, 

above-grade insulation include flashing, 

fiber-cement board, parging (stucco 

type material), treated plywood, or 

membrane material (EPDM* 

flexible roofing). 

•	 Note that some code jurisdictions 

may require a gap between exterior 

insulation and wood foundation 

elements to provide a termite 

inspection area.

•	 Install damp proofing or a polyethylene 

sheet over the footing to block 

capillary water wicking into the 

foundation side wall.

•	 Install a capillary break and vapor 

retarder under the entire slab consisting 

of at least a 6-mil polyethylene sheet 

or continuous rigid foam insulation 

approved for below-grade applications, 

on top of 4 to 6 inches of coarse gravel. 

•	 Install radon control measures 

(check local requirements and EPA 

recommendations).

*EPDM stands for Ethylene Propylene 

Diene Monomer. 

Slab Foundation System, Insulation, Moisture and Air Leakage Control

14.11

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.11
Basement & Conditioned Crawlspace Insulation, Moisture and Air Leakage Control

Sill gasket membrane

(also serves as capillary break)

Metal termite flashing

Concrete footing

below frost depth

Polyethylene or damp

proofing capillary break

Rigid fiberglass insulation

Polyethylene vapor barrier

Damp proofing

Perforated drainage

pipe embedded in

coarse gravel

Treated wood nailer

(bring vapor barrier

up to grade level)

Cavity insulation

= Sealant or Gasket

Cover insulation

exposed above grade

Rigid Insulation

Continuous

polyethylene

Damp proofing

Rigid insulation

Treated

wood nailer

Polyethylene or 

damp proofing 

capillary break

Rigid insulation

Rigid insulation

Damp proofing

Continuous

polyethylene

Polyethylene or 

damp proofing 

capillary break

Sill gasket membrane

(also serves as capillary break)

Metal termite flashing

Concrete footing

below frost depth

Polyethylene or damp

proofing capillary Break

Rigid fiberglass insulation

Polyethylene vapor

diffusion retarder

Damp proofing

Perforated drainage

pipe embedded in

coarse gravel

Radon reduction

3” plastic vent pipe

Cavity insulation

Cover insulation

exposed above grade

Rigid insulation

with foil facing

Damp proofing

Cavity

insulation

Polyethylene or

damp proofing

capillary break

Sill gasket membrane

(also serves as capillary break)

Metal termite flashing

Concrete footing

below frost depth

Polyethylene or damp

proofing capillary break

Rigid fiberglass insulation

Polyethylene vapor barrier

Damp proofing

Perforated drainage

pipe embedded in

coarse gravel

Treated wood nailer

(bring vapor barrier

up to grade level)

Cavity insulation

= Sealant or Gasket

Cover insulation

exposed above grade

Rigid Insulation

Continuous

polyethylene

Damp proofing

Rigid insulation

Treated

wood nailer

Polyethylene or 

damp proofing 

capillary break

Rigid insulation

Rigid insulation

Damp proofing

Continuous

polyethylene

Polyethylene or 

damp proofing 

capillary break

Sill gasket membrane

(also serves as capillary break)

Metal termite flashing

Concrete footing

Polyethylene or damp

proofing capillary Break

Rigid fiberglass insulation

Polyethylene vapor

diffusion retarder

Damp proofing

Perforated drainage

pipe embedded in

coarse gravel

Radon reduction

3” plastic vent pipe

Cavity insulation

Cover insulation

exposed above grade

Rigid insulation

with foil facing

Damp proofing

Cavity

insulation

Polyethylene or

damp proofing

capillary break

Sill gasket membrane

(also serves as capillary break)

Metal termite flashing

Concrete footing

below frost depth

Polyethylene or damp

proofing capillary break

Rigid fiberglass insulation

Polyethylene vapor barrier

Damp proofing

Perforated drainage

pipe embedded in

coarse gravel

Treated wood nailer

(bring vapor barrier

up to grade level)

Cavity insulation

= Sealant or Gasket

Cover insulation

exposed above grade

Rigid Insulation

Continuous

polyethylene

Damp proofing

Rigid insulation

Treated

wood nailer

Polyethylene or 

damp proofing 

capillary break

Rigid insulation

Rigid insulation

Damp proofing

Continuous

polyethylene

Polyethylene or 

damp proofing 

capillary break

Sill gasket membrane

(also serves as capillary break)

Metal termite flashing

Concrete footing

below frost depth

Polyethylene or damp

proofing capillary Break

Rigid fiberglass insulation

Polyethylene vapor

diffusion retarder

Damp proofing

Perforated drainage

pipe embedded in

coarse gravel

Radon reduction

3” plastic vent pipe

Cavity insulation

Cover insulation

exposed above grade

Rigid insulation

with foil facing

Damp proofing

Cavity

insulation

Polyethylene or

damp proofing

capillary break

Sill gasket membrane

(also serves as capillary break)

Metal termite flashing

Concrete footing

below frost depth

Polyethylene or damp

proofing capillary break

Rigid fiberglass insulation

Polyethylene vapor barrier

Damp proofing

Perforated drainage

pipe embedded in

coarse gravel

Treated wood nailer

(bring vapor barrier

up to grade level)

Cavity insulation

= Sealant or Gasket

Cover insulation

exposed above grade

Rigid Insulation

Continuous

polyethylene

Damp proofing

Rigid insulation

Treated

wood nailer

Polyethylene or 

damp proofing 

capillary break

Rigid insulation

Rigid insulation

Damp proofing

Continuous

polyethylene

Polyethylene or 

damp proofing 

capillary break

Sill gasket membrane

(also serves as capillary break)

Metal termite flashing

Concrete footing

below frost depth

Polyethylene or damp

proofing capillary Break

Rigid fiberglass insulation

Polyethylene vapor

diffusion retarder

Damp proofing

Perforated drainage

pipe embedded in

coarse gravel

Radon reduction

3” plastic vent pipe

Cavity insulation

Cover insulation

exposed above grade

Rigid insulation

with foil facing

Damp proofing

Cavity

insulation

Polyethylene or

damp proofing

capillary break

EXTERIOR CRAWLSPACE INSULATION INTERIOR CRAWLSPACE INSULATION

If depth does not extend two feet below grade, place 

remaining insulation horizontally along the ground.

EXTERIOR BASEMENT INSULATION

INTERIOR BASEMENT INSULATION

See more information on the following page.

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.12 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Sources & Additional Information

IBACOS. 2002. Consider the Crawlspace (www.buildingamerica.gov)

IBACOS. 2002. Don’t Forget About the Basement (www.buildingamerica.gov)

Lstiburek, Joseph. 2004. Builders Guide to Cold Climates (www.eeba.org/bookstore)

U.S. DOE, Technology Fact Sheet: Basement Insulation (www.buildingamerica.gov)

U.S. DOE, Technology Fact Sheet: Crawlspace Insulation (www.buildingamerica.gov)

U.S. EPA, Building Radon Out: A Step-By-Step Guide on How to Build Radon Resistent Homes (www.epa.gov/1999/iaq/radon)

Yost and Lstiburek. 2002. Basement Insulation Systems (www.buildingamerica.gov)

•	 Keep all untreated wood materials

away from contact with earth 

and concrete. 

•	 Design the house structure with

overhangs, gutters, drainage planes, 

and flashing to shed rainwater and 

conduct it away from the house.

•	 Slope the earth away from the house

and ensure that no irrigation strikes 

near the foundation. 

•	 Damp-proof all below-grade portions of

the exterior foundation wall to prevent 

the absorption of ground water.

•	 Use a sill gasket for air sealing.

•	 Install a protective shield such as

metal flashing, a plastic L bracket, or 

a membrane (such as EPDM flexible 

roofing material*) to block capillary 

water wicking into the wall from the 

foundation. The protective shield may 

also serve as a termite shield.

•	 Crawlspaces require a foundation

drain when the crawlspace floor is 

located below grade. Always install a 

foundation drain in basements. Install 

a foundation drain alongside the 

footing (not above it). The drain should 

rest in a bed of coarse gravel (no fines) 

that slopes away from the foundation 

and is covered with filter fabric.

•	 Exterior rigid fiberglass insulation

may provide a drainage plane that will 

channel water to the foundation drain 

and relieve hydrostatic pressure. 

•	 Exterior foundation wall insulation

requires a protective coating at 

above-grade applications. Examples 

of protective coverings for exterior, 

above-grade insulation include 

flashing, fiber-cement board, parging 

(stucco type material), treated plywood, 

or membrane material (EPDM* 

flexible roofing). 

•	 Note that some code jurisdictions

may require a gap between exterior 

insulation and wood foundation 

elements to provide a termite 

inspection area.

•	 Install damp proofing or a polyethylene

sheet over the footing to block 

capillary water from wicking into the 

foundation side wall.

•	 Install a capillary break and vapor

retarder under slabs and basement 

floors consisting of at least a 6-mil 

polyethylene sheet or continuous rigid 

foam insulation approved for belowgrade applications, on top of 4 to 6 

inches of coarse gravel.

•	 Install radon control measures

(check local requirements and EPA 

recommendations). 

*EPDM stands for Ethylene Propylene 

 Diene Monomer.

Crawlspace and Basement Foundation System Moisture and Air Leakage Control

•	 Exterior and interior insulation approaches may be combined to provide needed insulation levels.

•	 Properly installed exterior rigid fiberglass insulation provides the best moisture management properties of the available insulation types.

•	 Interior nailing strips for finished walls should be installed over interior rigid foam insulation (extruded polystyrene is more moisture

tolerant than expanded polystyrene) so that the foam is sandwiched between the nailing strip and the basement wall. 

•	 When interior foam insulation is applied directly to foundation walls, seal joints in the foam panels with adhesive or mastic.

•	 If interior blanket or batt insulation is used, it should be combined with exterior or interior rigid insulation attached directly to the

foundation wall. The blanket or batt insulation should be unfaced or have a facing that allows moisture to pass through. In a conditioned 

basement, the insulation should be covered with drywall that is tightly air sealed to keep interior moist air from condensing on the 

foundation wall.

Installation Tips

14.13

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.13
Sources & Additional Information

Building Science Corporation. 2010. “Enclosures That Work: Building Profiles,” Building Science Corporation, 

www.buildingscience.com/doctypes/enclosures-thatwork/etw-building-profiles

Lstiburek, J. W. 2000. Builders Guides. Minneapolis, MN. Energy and Environmental Building Association. www.eeba.org. 

Rigid Insulation

(minimum 1/2" thick)

Wood Furring

(minimum 3/4" thick)

Gypsum Board 

Masonry Wall 

Shallow Electrical Box

(surface-mounted on 

masonry interior)

Continuous 2x4 or 2x2 Horizontal Furring 

(acting as draft or fire stop; seal all 

service/wiring penetrations) 

Interior Gypsum Board with 

permeable or semi-permeable finish 

Semi-Permeable Rigid Insulation

(expanded polystyrene, extruded polystyrene, 

fiber-faced isocyanurate)

Wood Furring 

Gypsum Board 

Concrete 

Slab 

Latex Paint or other permeable or 

semi-permeable interior finish 

Masonry 

Wall 

Sloping Precast Masonry 

Sill with Precast Rib 

Treated Wood Spacer/Mounting 

Block to support window 

Sealant forming 

end dam 

Wood Sub-Jamb

(Positioned toward wall exterior so that face of interior window 

frame is flush with center point of rib in precast masonry sill)

Treated Wood 

Sub-Jamb 

Mounting Member 

("back-caulked") 

Sealant between 

masonry opening and 

treated wood sub-jamb 

Semi-vapor permeable rigid insulations used on the interior 

of wall assemblies should be unfaced or faced with permeable 

skins. Foil facings and polypropylene skins should be avoided.

Wood furring should be installed over rigid insulation; the 

rigid insulation should be continuous over the surface of the wall, 

except for the 2x4 furring near the ceiling. This blocking attaches 

directly to the masonry block and is above the insulation, not behind it.

Electrical boxes can be surface-mounted, 

eliminating chiseling or chipping masonry ELECTRICAL BOX 

WINDOW SILL DRAINAGE 

Source: EEBA 9.5 

Source: EEBA 9.7 

Source: EEBA 9.1 

Masonry Construction

14.15

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.15
Housewrap

Example of housewrap strategies

Minimize cuts in housewrap and seal all penetrations with tape or caulk.

Unroll sideways around house.

Fasten flaps of window "T-cut" 

to the inside of the framing.

Seal spigot 

at opening.

Tape housewrap according to manufacturer’s specifications at top plate,

 band joist, and horizontal seams, and secure with plastic-capped nails.

Housewrap should 

be overlapped shingle style.

Seal overlap with tape.

Overlap and seal housewrap 

to foundation side wall 

or flashing.

Caulk under housewrap 

and seal gap between 

electrical box and 

sheathing.

Seal floodlight 

at opening.

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP 

CAULK 

CAULK 

CAULK 

WINDOW 

Housewrap

Plastic-capped nails

Housewrap Tape

Sheathing

Tape

Housewrap Caulk

Sill Gasket

14.17

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.17
•	Do follow manufacturer’s instructions.

•	Do lap all layers properly—the upper layer should always be lapped over the lower layer.

•	Do weatherboard-lap horizontal joints at least 6 inches.

•	Do lap vertical joints 6 to 12 inches (depending on the potential for wind-driven rain).

•	Do use 1-inch minimum staples or housewrap nails spaced 12 to 18 inches throughout.

•	Do tape joints with housewrap tape.

•	Do allow drainage at the bottom of the siding.

•	Do extend housewrap over the sill plate and foundation joint.

• Do install housewrap such that water will never be allowed to flow to the inside of the wrap.

•	Do avoid complicated details in the design stage to prevent water-intrusion problems.

•	When sealant is required:

•	do use backing rods as needed,

•	do use sealant that is compatible with the climate, and materials it is being applied to,

•	do make sure surfaces are clean (free of dirt and loose material).

•	Do integrate wrap correctly with window flashing so that wrap goes over top edge of flashing.

•	Don’t forget to cover the gable ends.

•	Don’t forget to cover the band joists. If you wrap the wall before standing it, go back and insert 

a strip of house wrap to cover the band joist. The strip should extend 6 to 12 inches underneath 

the bottom edge of the wall wrap. 

•	Don’t forget to cover outside corners. Do overlap wrap 6 to 12 inches at corners.

•	Don’t rely on caulk or self-sticking tape to “fix” improper lapping of housewrap. Caulk will fail over time.

DO’s and DON’Ts of Housewrap

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.18 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Window Flashing

Window flashing details for home with housewrap and plywood or OSB wall sheathing

>12" >10"

Housewrap

Cap Nails 45 ̊ 6"

6"

CAULK

HOUSEWRAP 

HOUSEWRA

HOUSEWRAP 

HOUSEWRAP 

Self-adhesive 

Window Flashing

Tape

HOUSEWRAP 

HOUSEWRA

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP

HOUSEWRAP 

HOUSEWRAP 

EWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUS

HOUSEWRAP 

HOUSEWRAP 

OUSEWRAP

HOUSEWR

HOUSEWRAP 

HOUSEWRAP

>12" >10"

Housewrap

Cap Nails 45 ̊ 6"

6"

CAULK

HOUSEWRAP 

HOUSEWRA

HOUSEWRAP 

HOUSEWRAP 

Self-adhesive 

Window Flashing

Tape

HOUSEWRAP 

HOUSEWRA

HOUSEWRAP 

HOUSEWRAP 

HOUSEWRAP

HOUSEWRAP 

HOUSEWRAP 

EWRAP 

HOUSEWRAP 

HOUSEWRAP 

HOUS

HOUSEWRAP 

HOUSEWRAP 

OUSEWRAP

HOUSEWR

HOUSEWRAP 

HOUSEWRAP

STEP 1 - 

IF HOUSEWRAP HAS NOT YET BEEN INSTALLED

STEP 2 - SILL FLASHING STEP 3 - JAMB CAULKING

• Apply at least a 12-inch flap, or apron, of building paper or 

housewrap just below the window sill.

• If the window sill is close to the sill plate, the apron can extend all 

the way to the sill plate.

• The apron should extend at least 10 inches past the sides of the 

window opening, or to the first stud in open wall construction.

• Attach only the apron’s top edge with cap nails.

• Install self-adhesive flashing to the sill, ensuring that the 

flashing extends up jambs at least 6 inches.

• One commercial product comes with two removable strips 

over the adhesive. Remove the first strip to expose half of the 

adhesive and apply this area to the sill. Begin pressing in the 

middle of the sill and work towards the sides. Remove the 

second strip to expose the adhesive that will be used to apply 

the flashing below the window to the outside wall.

• Tape down the bottom corners of the flashing.

• Caulk the outside edges of the head and side jambs.

• Do not caulk across the sill.

• Install the window using corrosion-resistant nails and 

following manufacturer’s specifications.

• Cut the housewrap covering the rough opening in 

the shape of a modified “Y.”

• Fold the side and bottom flaps into the window 

opening and secure.

• Above the window opening, cut a head flap and 

flip it up to expose sheathing, and loosely tape in 

place out of the way.

STEP 1 - 

IF HOUSEWRAP HAS BEEN INSTALLED

14.19

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.19
CAULK

4" 1" HOUSEWRAP 

HOUSEWRAP 

HOUS

HOUSEWRAP 

HOUSEWRAP 

OUSEWRAP

HOUSEWR

Self-adhesive 

head flashing

Fold down

head flap

HOUSEWRAP

HOUSEWRAP

HOUSEWRA

HOUSEWRAP

HOUSEWRAP

HOUSEWRAP

HOUSEWRAP

Housewrap

secured to 

window flange 

with tape HOUSEW

HOUSE

HOUSEWRAP

HOUSEWRAP

Self-adhesive 

jamb flashing

Existing

apron

Head flap 

secured with tape

STEP 4 - JAMB AND HEAD FLASHING STEP 5 - SEAL ROUGH OPENING GAP

• Install self-adhesive jamb flashing extending 4 inches above 

the top of the head flange and even with the bottom of the 

sill flashing.

• Install self-adhesive head flashing extending 1 inch beyond 

the jamb flashing.

• If housewrap has been installed, be sure that the head flap, 

when it is folded down, will cover the top of the flashing.

• On the interior side of the window, seal the gap 

between the window and the rough opening with 

a backer rod or non-expanding foam and caulk. 

STEP 6 - IF APRON WAS INSTALLED STEP 6 - IF HEAD FLAP WAS CREATED

• If an apron was installed under the window, slip the 

housewrap or building paper under the apron.

• Tape the edges where the housewrap meets the 

window flange if housewrap is installed after flashing.

• If building paper is used, embed the edges in a bead 

of sealant where the paper meets the window flange.

• If a head flap was created, fold it over the head 

flashing and tape across the top window flange and 

the 45° angle seams.

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.20 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Wall-to-Roof Flashing

Kick-Out Diverter Flashing Details

Water runoff from roof-wall intersections can flow down the exterior wall and eventually find its way into the wall where it can 

cause serious damage. Anywhere roof sections adjoin wall sections, kick-out flashing should be used to divert water away from 

the walls and preferably into rain gutters where it can be carried down and away from the structure.

STEP 1 Apply drip edge and roof 

underlayment over roof deck. Continue 

lapping up the sidewall and over the 

water-resistive barrier (in this case 

housewrap) a minimum of 6 inches.

STEP 4 Install remaining sidewall 

flashing, appropriate counter flashing, 

and shingles in accordance with 

manufacturer’s instructions.

STEP 2 Install shingle starter strip at 

roof eave in accordance with roofing 

manufacturer’s instructions.

•	 Place seamless one-piece of non-corrosive 

kick-out diverter flashing as the first piece 

of step flashing. 

•	 Slide kick-out diverter up roof plane until the 

starter trough stops at the shingle starter strip.

•	 The diverter must be flat on the roof and 

flush to the sidewall.

•	 Fasten and seal diverter to the roof deck and 

starter strip. (Do not fasten to the sidewall.)

STEP 5 Apply self-adhesive flashing 

over top of wall flashing, diverter, and 

housewrap.

STEP 3 Place first shingle and next 

section of sidewall flashing over the

up-slope edge of diverter, lapping a 

minimum of 4 inches over diverter. 

(Sidewall flashing height requirement 

should be determined by design 

professional and local building codes.)

STEP 6 Install house wrap; cut the 

house wrap to fit over the self-adhesive 

flashing and sidewall flashing.

STEP 7 Apply siding over housewrap.

14.21

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.21
Wall-to-Roof Flashing

Kick-Out Diverter Flashing Details - Rigid Foam Insulation Installed as a Water-Resistive Barrier

Water runoff from roof-wall intersections can flow down the exterior wall and eventually find its way into the wall where it can cause 

serious damage. Anywhere roof sections adjoin wall sections; kick-out flashing should be used to divert water away from the walls and 

preferably into rain gutters where it can be carried away from the structure.

STEP 1 Apply drip edge and roof 

underlayment over roof deck and 

continue lapping up the sidewall and 

over the water-resistive barrier (in this 

case rigid foam insulation) a minimum 

of 7 inches.

STEP 4 Install remaining sidewall 

flashing, appropriate counter flashing 

and shingles in accordance with 

manufacturer’s instructions.

STEP 2 Install shingle starter strip at 

roof eave in accordance with roofing 

manufacturer’s instructions.

•	 Place seamless, one-piece, non-corrosive 

kick-out diverter flashing as the first piece 

of step flashing.

•	 Slide kick-out diverter up roof plane until the 

starter trough stops at the shingle starter strip.

•	 Diverter must be flat on the roof and flush 

to the sidewall.

•	 Fasten and seal diverter to the roof deck and 

starter strip. (Do not fasten to the sidewall.)

STEP 5 Apply self adhesive flashing 

over top of wall flashing, diverter and 

rigid foam insulation.

STEP 3 Place first shingle and 

next section of sidewall flashing over 

up-slope edge of diverter, lapping a 

minimum of 4” over diverter. 

(Sidewall flashing height requirement 

should be determined by design 

professional and local building codes.)

STEP 6 Apply construction tape 

over the self-adhered flashing. 

STEP 7 Apply siding over rigid 

foam insulation.

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.22 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Interior Air Sealing

Conventional construction requires tracking down and sealing multiple 

air leaks that ultimately lead to or through the exterior shell.

 1. Sill Plate & Rim Joist

 2. Stairs

 3. Wall & Ceiling Drywall

 4. Kneewalls

 5. Windows

 6. ICAT Can Light

 7. Electric Circuit Box

 8. Outlets & Switches

 9. Fireplace

10. Plumbing Penetrations

11. Attic Access

12. Doors

13. Cantilever

14. Skylight

15. Crawlspace Access

16. Registers

17. Exhaust Fan 

18. Garage Common Wall

19. Wall Adjoining Cavity

20. Tub

21. Interior Soffit

22. Plywood Floor Panels

12

7

18

4

20

5

13

14

15

21 17

9

11

10

2

3

22

1

6

8 19

16

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

14.23

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.23
Tape

Housewrap Caulk

Sil gasket

Gypsum

board

Structural

sheathing

Tape and joint

compound seal

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed to bottom plate

Drywall caulked or glued 

to top plate

Ceiling drywall taped

to wall drywall

Use rigid foam 

or sheet goods to 

seal joist cavities

Seal

Adhesive, Gasket or Caukling

Drywall

Hardboard,

rigid foam,

or sheet goods

Seal

HOUSEWRAP

HOUS

OUSEWRAP

HOUSEWRAP

Before installing 

the window, caulk 

the outside edges 

of the head and 

side jambs

Do not caulk

across the sill

CAULK

CAULK

Seal gap between 

window and rough

opening on interior

Recessed light fixtures 

should be rated for 

Insulated Ceiling Air 

Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight wire

connection from 

junction jox

Airtight

can

Decorative

cover Caulk

or gasket

Seal

Support sheathing

Electrical

panel

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to

drywall air barrier

Select boxes with 

built-in gasket

and sealant

Seal

Solid air barrier

material sealed at

perimeter and seams

CAULK

Air seal gasket

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimeter

Insulation in permanent

contact with subfloor

Tape

Rim joist Rigid or blown-in

foam insulation

Housewrap

Sill gasket

CAULK

Tape

Housewrap Caulk

Sil gasket

Gypsum

board

Structural

sheathing

Tape and joint

compound seal

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed to bottom plate

Drywall caulked or glued 

to top plate

Ceiling drywall taped

to wall drywall

Use rigid foam 

or sheet goods to 

seal joist cavities

Seal

Adhesive, Gasket or Caukling

Drywall

Hardboard,

rigid foam,

or sheet goods

Seal

HOUSEWRAP

HOUS

OUSEWRAP

HOUSEWRAP

Before installing 

the window, caulk 

the outside edges 

of the head and 

side jambs

Do not caulk

across the sill

CAULK

CAULK

Seal gap between 

window and rough

opening on interior

Recessed light fixtures 

should be rated for 

Insulated Ceiling Air 

Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight wire

connection from 

junction jox

Airtight

can

Decorative

cover Caulk

or gasket

Seal

Support sheathing

Electrical

panel

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to

drywall air barrier

Select boxes with 

built-in gasket

and sealant

Seal

Solid air barrier

material sealed at

perimeter and seams

CAULK

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Baseplate sealed 

to subfloor

Insulation in permanent

contact with subfloor

Tape

Rim joist Rigid or blown-in

foam insulation

Housewrap

Sill gasket

CAULK

Tape

Housewrap Caulk

Sil gasket

Gypsum

board

Structural

sheathing

Tape and joint

compound seal

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed to bottom plate

Drywall caulked or glued 

to top plate

Ceiling drywall taped

to wall drywall

Use rigid foam 

or sheet goods to 

seal joist cavities

Seal

Adhesive, Gasket or Caukling

Drywall

Hardboard,

rigid foam,

or sheet goods

Seal

HOUSEWRAP

HOUS

OUSEWRAP

HOUSEWRAP

Before installing 

the window, caulk 

the outside edges 

of the head and 

side jambs

Do not caulk

across the sill

CAULK

CAULK

Seal gap between 

window and rough

opening on interior

Recessed light fixtures 

should be rated for 

Insulated Ceiling Air 

Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight wire

connection from 

junction jox

Airtight

can

Decorative

cover Caulk

or gasket

Seal

Support sheathing

Electrical

panel

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to

drywall air barrier

Select boxes with 

built-in gasket

and sealant

Seal

Solid air barrier

material sealed at

perimeter and seams

CAULK

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Baseplate sealed 

to subfloor

Insulation in permanent

contact with subfloor

Tape

Rim joist Rigid or blown-in

foam insulation

Housewrap

Sill gasket

CAULK

Tape

Housewrap Caulk

Sil gasket

Gypsum

board

Structural

sheathing

Tape and joint

compound seal

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed to bottom plate

Drywall caulked or glued 

to top plate

Ceiling drywall taped

to wall drywall

Use rigid foam 

or sheet goods to 

seal joist cavities

Seal

Adhesive, Gasket or Caukling

Drywall

Hardboard,

rigid foam,

or sheet goods

Seal

HOUSEWRAP

HOUS

OUSEWRAP

HOUSEWRAP

Before installing 

the window, caulk 

the outside edges 

of the head and 

side jambs

Do not caulk

across the sill

CAULK

CAULK

Seal gap between 

window and rough

opening on interior

Recessed light fixtures 

should be rated for 

Insulated Ceiling Air 

Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight wire

connection from 

junction jox

Airtight

can

Decorative

cover Caulk

or gasket

Seal

Support sheathing

Electrical

panel

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to

drywall air barrier

Select boxes with 

built-in gasket

and sealant

Seal

Solid air barrier

material sealed at

perimeter and seams

CAULK

Attic

Use ENERGY STAR

Baseplate sealed 

to subfloor

Insulation in permanent

Tape

Rim joist Rigid or blown-in

foam insulation

Housewrap

Sill gasket

CAULK

7

10

4 5

9

1 2 3

6

8

Sill Plate & Rim Joist

Kneewalls

Electric Circuit Box

Plumbing Penetrations

Stairs

Windows

Outlets & Switches

Wall & Ceiling Drywall

ICAT Can Light

Fireplace

Direct vent fireplace through outside wall; 

no chimney needed, but seal fireplace alcove.

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.24 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Flange for sealing to 

drywall air barrier

built-in gasket 

and sealant

Seal

material sealed at 

parimeter and seams

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimenter

Insulation in permanent

contact with subfloor

Rigid insulation

Air seal gasket

Crawlspace

Rigid insulation

REGISTER

Seal all joints in 

boot and elbow

with mastic

Seal boots to 

sheet goods with 

caulk, mastic, or 

spray foam

CAULK

EXHAUST FAN If fan exhausts or 

draws air through 

sidewall, install hood

with louvered 

damper

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed; inside seam 

taped and mudded

GARAGE

Bottom plate caulked

or gasketed to subfloor

 on interior, exterior,

or both surfaces

Drywall caulked, 

glued or gasketed 

to top plate on interior, 

exterior, or both surfaces 

CAVITY

Continuous bead of

sealant or adhesive

Thin sheet goods 

as draftstop behind

tub or enclosure

Blocking

Solid air barrier

material sealed

at perimeter

CAULK

Use caulk or adhesive to

seal panels to joists at seams

sealant

Flange for sealing to 

drywall air barrier

Select boxes with 

built-in gasket 

and sealant

Seal

Solid air barrier

material sealed at 

parimeter and seams

CAULK

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimenter

Insulation in permanent

contact with subfloor

Rigid insulation

Air seal gasket

Crawlspace

Rigid insulation

REGISTER

Seal all joints in 

boot and elbow

with mastic

Seal boots to 

sheet goods with 

caulk, mastic, or 

spray foam

CAULK

EXHAUST FAN If fan exhausts or 

draws air through 

sidewall, install hood

with louvered 

damper

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed; inside seam 

taped and mudded

GARAGE

Bottom plate caulked

or gasketed to subfloor

 on interior, exterior,

or both surfaces

Drywall caulked, 

glued or gasketed 

to top plate on interior, 

exterior, or both surfaces 

CAVITY

Continuous bead of

sealant or adhesive

Thin sheet goods 

as draftstop behind

tub or enclosure

Blocking

Solid air barrier

material sealed

at perimeter

CAULK

Use caulk or adhesive to

seal panels to joists at seams

Flange for sealing to 

drywall air barrier

Select boxes with 

built-in gasket 

and sealant

Seal

Solid air barrier

material sealed at 

parimeter and seams

CAULK

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimenter

Insulation in permanent

contact with subfloor

Rigid insulation

Air seal gasket

Crawlspace

Rigid insulation

REGISTER

Seal all joints in 

boot and elbow

with mastic

Seal boots to 

sheet goods with 

caulk, mastic, or 

spray foam

CAULK

EXHAUST FAN If fan exhausts or 

draws air through 

sidewall, install hood

with louvered 

damper

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed; inside seam 

taped and mudded

GARAGE

Bottom plate caulked

or gasketed to subfloor

 on interior, exterior,

or both surfaces

Drywall caulked, 

glued or gasketed 

to top plate on interior, 

exterior, or both surfaces 

CAVITY

Continuous bead of

sealant or adhesive

Thin sheet goods 

as draftstop behind

tub or enclosure

Blocking

Solid air barrier

material sealed

at perimeter

CAULK

Use caulk or adhesive to

seal panels to joists at seams

Flange for sealing to 

drywall air barrier

Select boxes with 

built-in gasket 

and sealant

Seal

Solid air barrier

material sealed at 

parimeter and seams

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimenter

Insulation in permanent

contact with subfloor

Rigid insulation

Air seal gasket

Crawlspace

Rigid insulation

REGISTER

Seal all joints in 

boot and elbow

with mastic

Seal boots to 

sheet goods with 

caulk, mastic, or 

spray foam

CAULK

EXHAUST FAN If fan exhausts or 

draws air through 

sidewall, install hood

with louvered 

damper

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed; inside seam 

taped and mudded

GARAGE

Bottom plate caulked

or gasketed to subfloor

 on interior, exterior,

or both surfaces

Drywall caulked, 

glued or gasketed 

to top plate on interior, 

exterior, or both surfaces 

CAVITY

Continuous bead of

sealant or adhesive

Thin sheet goods 

as draftstop behind

tub or enclosure

Blocking

Solid air barrier

material sealed

at perimeter

CAULK

Use caulk or adhesive to

seal panels to joists at seams

12

15

18

21

13

16

19

22

11

14

17

20

Attic Access

Skylight

Exhaust Fan

Tub

Doors

Crawlspace Access

Garage Common Wall

Interior Soffit

Cantilever

Registers

Wall Adjoining Cavity

Plywood Floor Panels

14.25

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.25
Exterior Air Sealing with Insulating Sheathing Panels

This figure shows an approach to construction used in some Building America homes. The red line represents the 

thermal boundary, which is provided here by rigid insulation that is on the external side of the walls and the interior 

side of the foundation walls and roof. This exterior insulating sheathing provides both an air and thermal barrier for 

the walls. The non-vented attic is sealed and insulated along the roofline. Particular attention is paid to the intersection 

of the foundations, walls, and roof. Sealed combustion furnaces and water heaters do not require a vertical chimney.

5

3

4

6

7

2

 1. Sillplate & Rim Joist

 2. Windows

 3. Plumbing Penetrations

 4. Doors

 5. Exhaust Fan 

 6. Garage Common Wall

 7. Tub

Furring strip

Cladding

Tape seams

Caulk edges

CAULK

Insulated

sheathing panels

Insulating Sheathing Detail

1

1

2

3

4

5

6

7

14.27

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.27
Tape

Housewrap Caulk

Sil gasket

Gypsum

board

Structural

sheathing

Tape and joint

compound seal

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed to bottom plate

Drywall caulked, glued 

or gasketed to top plate

Ceiling drywall taped

to wall drywall

Use rigid foam 

or sheet goods to 

seal joist cavities

Seal

Hardboard

Seal

HOUSEWRAP

HOUSEWRAP

HOUSEWRAP

HOUSEWRAP

Before installing 

the window, caulk 

the outside edges 

of the head and 

side jambs

Do not caulk

across the sill

CAULK

CAULK

Seal gap between 

window and rough

opening on interior

Recessed light fixtures 

should be rated for 

Insulated Ceiling Air 

Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight wire 

connection from 

junction jox

Airtight

can

Decorative

cover Caulk

or Gasket

Sealant

Support sheathing

Electrical

panel

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to 

drywall air barrier

Select boxes with 

built-in gasket 

and sealant

Seal

Solid air barrier

material sealed at 

parimeter and seams

CAULK

Rigid insulation

Attic

Use ENERGY STAR

Install automatic

closer and gasket

or weatherstripping

Baseplate sealed 

to subfloor

Insulation in permanent

contact with subfloor

Tape

Rim joist Rigid or blown-in

foam insualtion

Housewrap

Sill gasket

CAULK

Tape

Sil gasket

board

Structural

sheathing

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed to bottom plate

gp p

Use rigid foam 

or sheet goods to 

seal joist cavities

Seal

Hardboard

Seal

HOUSEWRAP

HOUSEWRAP

HOUSEWRAP

HOUSEWRAP

Before installing 

the window, caulk 

the outside edges 

of the head and 

side jambs

Do not caulk

across the sill

CAULK

CAULK

Seal gap between 

window and rough

opening on interior

Recessed light fixtures 

should be rated for 

Insulated Ceiling Air 

Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight wire 

connection from 

junction jox

Airtight

can

Decorative

cover Caulk

or Gasket

Sealant

Support sheathing

Electrical

panel

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to 

drywall air barrier

Select boxes with 

built-in gasket 

and sealant

Seal

Solid air barrier

material sealed at 

parimeter and seams

CAULK

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimenter

Insulation in permanent

contact with subfloor

Air seal gasket

Rigid insulation

REGISTER

Seal all joints in 

Seal boots to 

sheet goods with 

caulk, mastic, or 

spray foam

Tape

Rim joist Rigid or blown-in

foam insualtion

Sill gasket

Use rigid foam 

or sheet goods to 

seal joist cavities

Seal

Hardboard

Seal

HOU

HOUSEWRAP

HOUSEWRAP

oe ead ad 

side jambs

Do not caulk

across the sill

CAULK

CAULK

Seal gap between 

window and rough

opening on interior

AIR TIGHTNESS 

LABEL

Airtight

can

Caulk

or Gasket

Suppor

Elect

pan

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to 

drywall air barrier

Select boxes with 

built-in gasket 

and sealant

Seal

Solid air barrier

material sealed at 

parimeter and seams

CAULK

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Basepla

to subfl

Blocking betwee

sealed at per

Insulation in per

contact with su

Rigid insulation

Air seal gasket

Crawlspace

Rigid insulation

REGISTER

Drywall caulked, glued 

or gasketed; inside seam 

taped and mudded

GARAGE

Drywall caulked, 

glued or gasketed 

to top plate on interior, 

exterior, or both surfaces 

1 Sill Plate & Rim Joist 2 Windows

HOUSEWRAP

P

en 

ugh

rior

g

should be rated for 

Insulated Ceiling Air 

Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight wire 

connection from 

junction jox

Airtight

can

Decorative

cover Caulk

or Gasket

Sealant

Support sheathing

Electrical

panel

Seal wire

connection

Seal

s

CAULK

omatic

 gasket

rstripping

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimenter

Insulation in permanent

contact with subfloor

REGISTER

Seal all joints in 

boot and elbow

with mastic

Seal boots to 

sheet goods with 

caulk, mastic, or 

spray foam

ued 

3 Plumbing Penetrations 4 Doors

Seal

Hardboard

Seal

CAULK

Seal gap between 

window and rough

opening on interior

Sealant

Support sheathing

Electrical

panel

Seal wire

connection

Nailing

flange Built-in

sealant

Flange for sealing to 

drywall air barrier

Select boxes with 

built-in gasket 

and sealant

Seal

Solid air barrier

material sealed at 

parimeter and seams

CAULK

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimenter

Insulation in permanent

contact with subfloor

Rigid insulation

Air seal gasket

Crawlspace

Rigid insulation

REGISTER

Seal all joints in 

boot and elbow

with mastic

Seal boots to 

sheet goods with 

caulk, mastic, or 

spray foam

CAULK

EXHAUST FAN If fan exhausts or 

draws air through 

sidewall, install hood

with louvered 

damper

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed; inside seam 

taped and mudded

GARAGE

Bottom plate caulked

or gasketed to subfloor

 on interior, exterior,

or both surfaces

Drywall caulked, 

glued or gasketed 

to top plate on interior, 

exterior, or both surfaces 

CAVITY

Blocking

6

5

7

Exhaust Fan

Garage Common Wall Tub Plumbing Floor Penetrations

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY 

labeled do

Rigid insulation

Air seal gasket

Cra

Rigid 

CAULK

EXHAUST FAN If fan exhausts or 

draws air through 

sidewall, install hood

with louvered 

damper

Bo

or 

D

o

ta

Continuous bead of

sealant or adhesive

Thin sheet goods 

as draftstop behind

tub or enclosure

Blocking

Solid 

mate

at 

n

t

es with 

ket 

t

Seal

Solid air barrier

material sealed at 

parimeter and seams

CAULK

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Baseplate sealed 

to subfloor

Blocking between joists,

sealed at perimenter

Insulation in permanent

contact with subfloor

Air seal gasket

Crawlspace

Rigid insulation

REGISTER

Seal all joints in 

boot and elbow

with mastic

Seal boots to 

sheet goods with 

caulk, mastic, or 

spray foam

s or 

ugh 

 hood

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed; inside seam 

taped and mudded

GARAGE

Bottom plate caulked

or gasketed to subfloor

 on interior, exterior,

or both surfaces

Drywall caulked, 

glued or gasketed 

to top plate on interior, 

exterior, or both surfaces 

CAVITY

Solid air barrier

material sealed

at perimeter

CAULK

Use caulk or adhesive to

seal panels to joists at seams

Air seal gasket

between trim

and panel

Rigid insulation

Attic

Use ENERGY STAR

labeled door

Install automatic

closer and gasket

or weatherstripping

Baseplate 

to subfloo

Blocking between j

sealed at perim

Insulation in perm

contact with subfl

Rigid insulation

Air seal gasket

Crawlspace

Rigid insulation

REGISTER

Se

bo

wi

Se

sh

ca

sp

CAULK

EXHAUST FAN If fan exhausts or 

draws air through 

sidewall, install hood

with louvered 

damper

Bottom plate caulked

or gasketed to subfloor

Drywall caulked, glued 

or gasketed; inside seam 

taped and mudded

GARAGE

Bottom plate caulked

or gasketed to subfloor

 on interior, exterior,

or both surfaces

Drywall caulked, 

glued or gasketed 

to top plate on interior, 

exterior, or both surfaces 

Continuous bead of

sealant or adhesive

Thin sheet goods 

as draftstop behind

tub or enclosure

Blocking

Solid air barrier

material sealed

at perimeter

CAULK

Use caulk or 

seal panels to jo

Keep pipes out of exterior walls and

seal penetrations through floor.

Keep pipe runs parallel and close to 

studs. Don’t compress insulation.

Insulate pipes exposed

to unconditioned areas

Seal penetrations

through rim joists.

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.28 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Sources & Additional Information

Lstiburek, J. W. 2000. Builders Guides. Energy and Environmental Building Association. www.eeba.org. 

U.S. DOE. Technology Fact Sheet on Air Sealing.

NAHB Research Center. www.toolbase.org: click on New Building Technology > Plumbing > Distribution Systems > Air Admittance Vents

Plumbing 

Vent 

Wall 

Top Plate 

Sealant between 

gasket and plate 

Staples 

Caulk/sealant 

Caulk/ 

Sealant 

Floor Insulation Pipe 

Exterior Wall 

 Rim 

Joist 

Another trade may have 

completed this step.

Confirm with the site 

supervisor. If not, and 

you need to complete 

the step yourself, ensure 

that the necessary 

materials are available 

onsite.

Vent pipe may be eliminated with an air-admittance valve in some jurisdictions.

Seal all plumbing and electrical penetrations.

Insulate and air seal behind tub.

Draft stop behind enclosure.

Keep pipes out of exterior walls and seal

holes through floor.

Seal holes through rim joists.

Insulate pipes 

 exposed to 

 unconditioned 

 areas

Be careful not to compress or disrupt floor 

insulation, if it is present. Keep pipe runs 

parallel and close to studs, leaving more room

for insulation.

Prefabricated roof-vent pipe flashing can be adapted as air-sealing gaskets.

Continuous bead 

of sealant or 

adhesive 

Thin sheet 

goods as draft 

stop behind tub 

or enclosure 

Blocking 

CAULK 

Exterior Wall 

Draft Stop 

Plumbing Air Sealing

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Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.29
Sources & Additional Information

Lstiburek, J.W. 2000. Builder Guide Hot-Humid Climates. Minneapolis, MN: Energy and Environmental Building Association (ww.eeba.org).

U.S. DOE. Technology Fact Sheet on Air Sealing (www.eere.energy.gov/buildings/documents/pdfs/26448.pdf).

Ceiling fans should be wired to a wall switch.

Seal all exterior penetrations, such as 

porch light fixtures, phone, security, 

cable and electric service holes, with 

caulk, spray foam, or gaskets - note 

that foam degrades in sunlight.

Use air-tight outlet boxes 

or seal standard boxes.

Seal standard plastic 

 electrical box at face 

 to drywall with joint 

 compound or cover 

 the plate gasket 

 with caulk or foam. 

Seal light fixture boxes to drywall with caulk or foam.

Seal bath fan box to drywall 

with caulk or foam.

Caulk/seal/foam all holes for electrical wires 

at top and bottom plates of exterior walls.

Run wiring along bottom plate at exterior wall.

NOTE: Some codes require wires to be held up from

bottom plates 6"-8" to protect from future drilling through plates.

Run wiring 

along side 

of stud at

exterior wall

and along 

plates

Recessed light fixtures should be rated for Insulated Ceiling Air Tight (ICAT).

AIR TIGHTNESS 

LABEL

Airtight Wire 

Connection From 

Junction Box 

Airtight Can 

EXTERIOR WALL

Caulk 

Seal Wire

Connection

Sealant

Support Sheathing

Electrical

Panel

Flange for sealing to 

drywall air barrier

Nailing

Flange

Built-in

Gasket

Built-in

Sealant

Caulk

Caulk at wire

penetrations

Decorative 

Cover 

CAULK 

CAULK 

Standard Plastic

Electrical Box

Air Sealed

Electrical Box

AIRTIGHTNESS LABEL 

Electrical Air Sealing

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CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.31
Installing Fiberglass Batt Insulation

Always:

 Avoid gaps, tight turns, and compressions.

 Cut insulation to fit snugly in non-standard spaces.

 Slit batts to fit around wiring and plumbing.

 Notch out around electrical boxes and use scraps to fill 

in behind.

•	 Install long runs first – then use scraps to fill in smaller 

spaces and gaps.

•	 Use unfaced batts in humid climates.

•	 Even if blown-in insulation is to be generally applied, 

use fiberglass batts to insulate areas that will be 

inaccessible to the blown-in insulation, such as 

behind bath enclosures and fireplaces.

Walls:

 Friction-fit the batts in place until covered by drywall 

or sheathing.

 Insulate before installing stairs, tubs, and other 

features that will block access.

Knee Walls:

 Seal knee wall to create a continuous air barrier. Close air 

gaps between floor joists under attic rooms. Insulate and 

air seal the rafter space along the sloping ceiling of the 

knee wall attic space or insulate and air seal the roofline, 

wall, and floor.

 Rafters should receive R-19 or R-30 insulation.

 Cover rafters with a sealed air barrier (such as drywall 

or foam board).

 Caulk the barrier to the top plate of the wall below the 

attic space and to the top plate of the knee wall itself.

 Seal all other cracks and holes.

Ceilings:

 Insulate and seal the attic access door

 Install insulation over ICAT-rated recessed cans.

 Verify ventilation pathways.

 Install insulation baffles between attic rafters in vented attics.

Band Joists:

 Place insulation in the cavities between joists and subfloor.

 Caulk bottom plate to subfloor.

 Caulk band joist to subfloor and plates and insulate.

 Caulk bottom plate to subfloor.

Under Floor Insulation:

 An insulated, unvented crawlspace is preferred rather than 

insulating under the floor. If under-floor insulation is to 

be used, it can be held in place with metal staves, lathe, 

stainless steel wire, or twine.

 If truss systems are used under floors, an approach better 

than batt insulation is to install netting or rigid insulation 

to the underside of the floor trusses and fill the joist cavity 

with blown-in insulation.

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CHAPTER 14. FIELD GUIDES FOR INSTALLERS

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Installing Windows in Walls with External Rigid Foam Insulation

Installing rigid foam insulation on exterior walls reduces thermal bridging and may reduce the chance 

of condensation in wall cavities. Many cold-climate builders now install 4 or 6 inches of EPS, XPS, or 

polyisocyanuarate rigid insulation on exterior walls.

Innies or Outies?

Builders installing thick exterior wall foam can install windows two ways: with the window flanges in the same plane as 

the back of the siding or with the window flanges in the same plane as the OSB or plywood wall sheathing.

The following apply to any window installation:

1. Foam panels should be installed with windows in mind—windows should not be installed where there is a 

seam in the foam sheathing, even if the foam is taped.

2. Water management details should specify that flashing around the perimeter of the window must tie 

into a water-resistive barrier regardless of the approach taken.

3. Ensure that foam sheathing does not bear the weight of the window. The weight of the window should 

be supported by the wall frame.

Interior Ledge Window Installations:

STEP 1 Rough in window openings, 

oversizing by 1 1⁄2 inches in both 

dimensions.

STEP 2 Line rough opening with a 

frame made of plywood strips 3⁄4” thick 

by wall dimension + width of foam (the 

plywood should be flush on the interior 

surface and extend to the anticipated

outside face of the foam).

STEP 3 Install the exterior foam. 

The outer face of the foam should 

be flush with the outer edge of the 

plywood frame.

Continued on following page

14.35

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.35
Sources & Additional Information

Building Science Corporation. 2007. Guide to Insulating Sheathing, Building Science Corporation, 

www.buildingscience.com/documents/guides-and-manuals/gm-guide-insulating-sheathing 

Interior Ledge Window Installations - Continued

STEP 4 Install housewrap. 

Cut modified “I” over window.

STEP 7 Install window; 

plumb, level, and square as per 

manufacturer’s instructions.

STEP 8 Install jamb flashing first; 

install a drip cap (if applicable); 

install head flashing.

STEP 5 Fold in housewrap at jambs 

and sill. Fold back temporarily at jamb. 

Install backdam on sill.

STEP 9 Fold down head housewrap; 

apply corner patches at head; air seal 

window around the entire perimeter on the 

interior with sealant or non-expanding foam.

STEP 10 Install vertical wood 

strapping on top of the foam and 

housewrap to use when attaching siding.

STEP 6 Install adhesive-backed sill 

flashing and corner flashing patches at 

sill. Apply sealant at jambs, head, and sill.

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.36 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
STEP 1 Install OSB and 

housewrap on wood frame wall. 

STEP 4 Install adhesive-backed 

sill flashing and corner flashing 

patches at sill.

STEP 7 Install jamb flashing first; 

install a drip cap (if applicable); 

install head flashing.

STEP 2 Cut modified “I” in housewrap

STEP 5 Apply sealant at jambs, 

head, and sill.

STEP 8 Fold down head housewrap.

STEP 3 Fold housewrap in at jambs 

and sill. Temporarily fold up housewrap 

at head. Install backdam.

STEP 6 Install window; plumb, 

level, and square as per manufacturer’s 

instructions.

STEP 9 Apply corner patches at 

head; air seal window around entire 

perimeter on the interior with sealant 

or non-expanding foam; install foam 

sheathing over housewrap.

Exterior Ledge Window Installations:

14.37

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.37
Duct Location – Dropped Ceiling Soffit

Ducts can be placed in a dropped ceiling soffit to keep them in conditioned space.

STEP 1 Use Manual J to determine appropriate HVAC size.

STEP 2 Design duct layout plan emphasizing compact layout with inside wall throws and air handler located 

in conditioned space. For cost savings consider using transoms over doors and one central return instead of 

ducted returns.

STEP 3 Hold meeting at home site after dry-in with designer, HVAC installer, framer, sheetrocker, other pertinent 

trades to discuss approach, if this is a new method.

STEP 4 Install sheetrock above chase. One method is to keep top plate of non-load bearing interior walls 3⁄4 inch 

from bottom cord of roof trusses. Slip drywall in this space.

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CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.39
STEP 5 Fabricate and seal ducts on the ground. Use hard ducts wherever possible. Fabricate a duct board box 

affixed to trunk line to serve as supply boot.

Supply boot comes directly from main trunk, as shown in “improved method” rather than connecting boot to 

trunk with a length of flex duct, as shown in original method. Thus duct chase can be narrower. 

Hard Duct

Hard ductwork is used wherever possible.

Flex Duct

Original method Improved method After framing

STEP 7 Install sheetrock around 

ducts to form chase, when sheetrocking 

the rest of the house (this is the second 

visit for sheetrockers).

Ducts are enclosed in soffits that add 

architectural interest to finished rooms.

STEP 6 Hang duct from the drywall 

using 2” nylon strapping material.

STEP 8 Install air handler in 

conditioned space in interior closet 

with large return air grill located 

over air handler. Use transoms over 

bedroom doors for return air path.

Air handler is located in the home in a 

closet with return grill above. Transoms 

over interior doors provide a return

 air path.

Fonorow, Ken, Dave Jenkins, Stephanie Thomas-Rees, and Subrato Chandra. 2010. 

“Low-Cost Interior Duct Systems for High-Performance Homes in Hot Climates,” 

Proceedings of the 2010 ACEEE Summer Study on Energy Efficiency in Buildings, 

Pacific Grove, CA, http://www.aceee.org/conf/10ss/index.htm

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.40 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Duct Location – In Open Web Floor Trusses Between Floors

Ducts can be placed in open web trusses between floors to keep them in conditioned space.

Rim joists must be thoroughly air sealed.

14.41

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.41
Air Handler and Duct Sealing

Mastic or caulk 

Mastic 

Collar with strap; 

mastic on take-off 

Mastic or caulk Filter Rack 

Mastic to seal 

refrigerant and 

condensate line 

Mastic 

Mastic 

Mastic 

Mastic all corners 

of metal plenums 

Mastic plenum 

to air handler 

Mastic exterior of collars 

Mastic or tape 

exterior of duct board 

RETURN 

SUPPLY 

Mastic collars to 

metal plenum on 

inside or outside 

Never puncture inner liner. If repair is 

needed, install a coupling and seal properly.

Strap inner liner and

outer insulation

Use wide straps to support flex duct

spaced at 5-foot intervals

Run lines straight

using metal elbows at

bends and corners

Mastic 

boot seams

Mastic before 

attaching flex 

duct

REGISTER

Seal

joints

in boots

Seal boots to sheet goods (drywall/subfloor) 

with caulk, mastic, or spray foam. 

Aluminum-backed butyl tape seal to 

drywall for ceiling and sidewall registers.

Seal metal or flex to boot or elbow 

and joints in elbow with mastic.

AIR HANDLER

FLEX DUCT

SUPPLY AND RETURN PLENUMS

BOOTS

Mastic is a gooey adhesive that is applied wet. It fills gaps and dries to a soft solid. Mastics may or may not contain reinforcing 

fibers, and they may be used with reinforcing mesh tape.

14.43

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.43
Ductless Heat Pump Installers Guide

Northwest Energy Efficency Alliance Ductless Heat Pump Project www.ductless.com

Best Practices for

Ductless Heat Pump

Installations A Contractor’s Guide

A quality ductless heat pump installation results from attention to details including: tools, 

installation and homeowner education. This guide provides information and suggestions to 

help you achieve successful ductless heat pump installations. Quality installations result 

in minimal call backs, more customer referrals, and increased awareness of ductless heat 

pump technology.

Installation Best Practices 

•	Follow manufacturers’ installation instructions. This guide is not intended to replace manufacturers’ specifications.

Outdoor Unit (Compressor):

• Set the unit on a stable, level surface.

•		Risers are essential to prevent snow and debris build-up and should be installed to

allow better drainage of defrost water.

•		Outdoor units should be secured to the pad, risers, and/or surface on which they

are set using bolts and/or adhesive.

Refrigerant Tubing:

•	Factory tubing flares and fittings are NOT TO BE REUSED.

•	Create new flares using appropriate R410A flaring tool & measurement gauge.

•	Apply refrigerant oil to the end of each flare.

•	Connect tubing with R410A nuts (supplied with indoor and outdoor units) using

a torque wrench tightened to manufacturer’s specifications.

Refrigerant Charge:

•	Adjust refrigerant charge ONLY IF NECESSARY. Most installations do not require

adjustment from pre-charge levels.

•	Gauges are not needed to verify refrigerant levels. (A scale should be used

when adding or removing refrigerant.)

• 	Consult the manufacturer’s installation manual to verify refrigerant protocols, specifications can often change.

Line Set Insulation and Protection

•		Insulation must cover entire line set length to avoid condensation and decreased

efficiency.

•		Once insulated, protect the outdoor portion of line set with rigid line hide to avoid

premature degradation damage to the insulation.

•		All penetrations through the shell of the home must be sealed with an insulative sealant.

Condensate Drain:

• Must slope downhill and can be routed with line set or run to a different termination point.

Improper Flaring

Inclined Surface

damaged

Cracked Uneven

thickness

Make sure proper

flare nut is fitted

Inner surface

must be

flaw-free

Smooth

all around

Refrigerant Tube

Required Tools

R410A

Gauge and

Hose Set

R410A

Specific

Flaring

Tools

Torque

Wrench

Programmable

Refrigerant

Charging

Scale

14.45

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.45
Disclaimer: This document is only to be used as a general guide for providing quality installations. For complete information regarding installation 

requirements, features, benefits, operation, and maintenance, review the manufacturer’s installation manual of the product being installed. 

Images of specific manufacturer product lines are not placed as endorsements, nor does this guide guarantee their quality.

Well Installed Outdoor and Indoor Unit = Happy Homeowner

Anchor Foot to Riser

Indoor Unit is Installed High on Wall

Indoor Unit is Level

Indoor Unit is Centrally Located in Home

for Best Air Circulation

Rigid Line Hide

Adhesive

Riser Block

Wall

Penetrations

Sealed With

Insulative

Sealant

Pad Compacted Ground		

An initiative of the Northwest Energy Efficiency Alliance, an alliance of NW Utilities and energy efficiency partners. 

Homeowner Education

•		Ensure homeowner has a copy of the Manufacturers Operation Manual that is

provided with the indoor unit. Refer to this manual as you perform a walkthrough

of unit operation.

•		Provide homeowner with a copy of the “Homeowner’s Guide” and remind

homeowners of www.GoingDuctless.com for more information about ductless

heating and cooling systems.

• Educated homeowners reduce call backs and promote your services!

Contractor Resources

•	For information on becoming a Project-oriented contractor, visit www.NWDuctless.com or call (503) 808-9003.

Project-oriented contractors are eligible to perform installations that receive utility rebates of up to $1,500!

Northwest Energy Efficency Alliance Ductless Heat Pump Project www.ductless.com

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.46 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Ice Dam Prevention

Ice dams are hazardous for buildings and people. Use the following guidance to minimize 

chances of ice dams forming on your homes.

Ice Dam Formation - 

Ice dams can form when the roof deck 

temperature is above freezing and the 

air is below freezing. 

Melted snow eventually reaches the 

colder edge of the roof where it refreezes, 

creating an ice dam that collects more 

water and ice. The ice dam is often 

not visible under the snow layer on the 

roof except for the telltale icicles, which 

indicate melting is occurring somewhere on 

the roof. (Source Lstiburek 2011, Building 

Science Corporation)

Three Steps to Ice Dam Control 

in a Vented Attic – 

1) Construct an airtight ceiling plane. Limit 

the number of holes through the ceiling and 

air seal every one. 

2) Insulate well, especially over the top 

plates, use raised heel trusses if needed to 

get full insulation coverage. 

3) Vent the underside of the roof deck, 

with vent screens at every rafter bay and a 

2-inch airspace under the sheathing where 

ground snow loads are greater than 30 lb/ft2. 

(Source Lstiburek 2011, 

Building Science Corporation)

14.47

CHAPTER 14. FIELD GUIDES FOR INSTALLERS

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 14.47
Sources & Additional Information

Lstiburek, Joseph. 2011. Dam Ice Dam, Insight 046, Feb. 2011, Building Science Corporation, 

www.buildingscience.com/documents/insights/bsi-046-dam-ice-dam/

Ice Dam Control in an Unvented 

Attic with Insulation above 

Roof Deck –

Cover roof sheathing with a fully adhered 

air barrier membrane. Install two layers (to 

R-50 or greater) of rigid insulation over air 

barrier, stagger the seams. Note there is 

no vented space under the roof cladding 

to compensate for the insulation value of 

the snow layer. This roof should be used 

where the ground snow load is less than 

50 lb/ft2. With ground snow loads greater 

than 50 lb/ft2, provide a ventilation space 

under the roof cladding as shown in 

Figure 4 (Source Lstiburek 2011, Building 

Science Corporation).

Ice Dam Control in an Unvented 

Attic with Insulation above Roof 

Deck in High-Snow-Load Areas – 

In regions with snow loads greater than 

50 lb/ft2, the snow can provide enough 

thermal resistance to allow the roof 

cladding to be above freezing even when 

the air temperature is below freezing (one 

foot of snow = R-10 to R-15). To prevent ice 

damming with an unvented attic in these 

conditions, construct a “vented over-roof” 

over the top of the “unvented compact 

roof” as shown above (Source Lstiburek 

2011, Building Science Corporation).

CHAPTER 14 / BUILDING AMERICA BEST PRACTICES SERIES

14.48 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Several builders are building energy-efficient homes in the cold and very cold climates. The following case 

studies showcase five cold climate builders who worked with Building America research team to build homes 

that exceeded the Building America benchmark by 40% or more. The energy-efficient measures they incorporate 

in their homes are summarized in the table below.

Table 1. Summary of Energy-Efficiency Measures Incorporated in Case Study Homes 

in the Cold Climate

Measure Devoted Builders 

Kennewick, WA

Nelson 

Construction 

Farmington, CT

Rural Development 

Incorporated, 

Turners Falls, MA 

S&A Homes 

Pittsburgh, PA

Shaw Construction 

Grand Junction, CO

Project Mediterranean 

Villas, Pasco 

WA; 230 duplex 

& triplex units, 

1,140-2,100 ft2, 

market rate

Hamilton Way, 

Farmington CT; 

10 single-family 

homes, 2,960-

3,540 ft2, market 

rate

Wisdom Way Solar 

Village, Greenfield, 

MA; 20 duplex 

units, 1,140-1,770 

ft2, affordable 

East Liberty 

Development Inc., 

6 single-family 

urban infill, 3,100 

ft2, above market 

rate

City of Aspen 

Burlingame Ranch 

Phase 1, 84 units 

in 15 multi-family 

buildings, 1,325 ft2, 

affordable

HERS 54-68 53-54 8-18 51-55 54-62

Walls R-25 ICF 2x6 24-in. o.c. Double walled 

(two 2x4 16-in. o.c. 

walls, 5” apart)

2x6 24-inch o.c. 2x6 24-in. o.c.

Wall 

Insulation

R-25 ICF 2-inch foil-faced 

polyisocyanurate 

R-13 sheathing, 

plus R-19 cellulose 

in stud cavities

R-42 dense-pack, 

dry blown cellulose

R-24 blown 

fiberglass

R-24 of 3.5-in. 

high-density 

spray foam

Attic 

Insulation

R-49 blown-in 

cellulose on 

ceiling

R-50 blown-in 

fiberglass on 

ceiling

R-50 blown-in 

cellulose on ceiling

R-49 blown-in 

fiberglass on 

ceiling

R-50 high-density 

spray foam on 

sloped ceiling, 

R-38 on flat ceiling

40% Whole-House Energy Savings 

in the Cold and Very Cold Climates

Case Studies

CS.1

BUILDING AMERICA BEST PRACTICES SERIES / CASE STUDIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 CS.1
Measure Devoted Builders 

Kennewick, WA

Nelson 

Construction 

Farmington, CT

Rural Development 

Incorporated, 

Turners Falls, MA 

S&A Homes 

Pittsburgh, PA

Shaw Construction 

Grand Junction, CO

Foundation 

Insulation

R-25 ICF perimeter 

foundation 

insulation with 

floating slab 

2-inch/R-10 

XPS below slab; 

2-inch/R-10 XPS 

in thermomass 

basement walls

Full uninsulated 

basement with 

R-40 blown 

cellulose under 

first floor

Precast concrete 

basement walls 

with steelreinforced concrete 

studs and 2.5 in. 

XPS R-12.5

Slab w R-13 XPS 

edge; some 

basements with 

R-13 interior 

polyisocyanurate; 

R-28 spray-foam 

insulation on 

ground under slab.

Ducts In conditioned 

space or in attic 

covered with spray 

foam and blown 

cellulose

In conditioned 

space in dropped 

ceiling or between 

joists

No ducts In conditioned 

space in open-web 

floor trusses

No ducts

Air Handler In conditioned 

space

In conditioned 

basement

None In conditioned 

basement

None

Tested Air 

Leakage and 

Sealing

Tested at 0.8 to 

2.0 ACH at 50 Pa; 

spray foam ceiling 

deck

Tested at <3.0 ACH 

at 50 Pa; foam 

critical seal of rim 

and floor joists

Tested at 1.1 to 1.5 

ACH at 50 Pa

Tested at 3.0 

ACH at 50 Pa; all 

penetrations and 

studs sealed

Tested at 2.5 in2

leakage per 100 ft2

of envelope

HVAC 8.5 HSPF/14 SEER 

heat pumps

94% AFUE gas 

furnace; SEER 14 

air conditioner

Small sealedcombustion 83% 

AFUE gas-fired 

space heater on 

main floor; no AC

Two-stage 96% 

AFUE gas furnace 

w multi-speed 

blower; SEER-14 

AC 

0.9 AFUE 

condensing 

gas boiler with 

baseboard hot 

water radiators

Windows U-0.29 U-0.32, SHGC 

0.27, double-pane, 

low-e, vinyl-framed

Triple-pane U-0.18 

on north/east/west 

sides; double-pane 

U-0.26 on south 

side

U-0.33, SHGC 0.30, 

double-pane

U-0.37, SHGC-0.33 

fiberglass-framed, 

double-pane

Water 

Heating

84% EF tankless 

gas water heater

82% EF tankless 

gas water heater

Solar thermal 

with tankless gas 

backup 

82% EF tankless 

gas water heater

Solar thermal with 

gas boiler backup

Ventilation Energy-recovery 

ventilator

Temp- and timercontrolled fresh 

air intake; exhaust 

fan ducted to draw 

from main living 

space; transfer 

grilles

Continuous 

bathroom exhaust

Passive fresh air 

duct to return 

plenum; fan-cycler 

on 50% of time 

for fresh air 

circulation, bath 

exhausts

Heat-recovery 

ventilator

CASE STUDIES / BUILDING AMERICA BEST PRACTICES SERIES

CS.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Measure Devoted Builders 

Kennewick, WA

Nelson 

Construction 

Farmington, CT

Rural Development 

Incorporated, 

Turners Falls, MA 

S&A Homes 

Pittsburgh, PA

Shaw Construction 

Grand Junction, CO

Green 3-star BuiltGreen 

certified homes 

2008 “Best Energy 

Efficient Green 

Community” by 

CT Home Builders 

Association; 2010 

NAHB Energy 

Value Housing gold 

award

LEED Platinum Meets LEED 

(not certified)

LEED Certified

Lighting and 

Appliances

70% CFL lighting; 

refrigerators, 

dishwashers, and 

clothes washers

100% CFLs; 

optional appliances

100% CFLs; 

refrigerator, 

dishwasher

100% CFLs; 

refrigerator, 

dishwashers, and 

clothes washer

90% CFL; 

refrigerator, 

dishwashers, 

clothes washers, 

ceiling fans

Solar No Optional 7-kW PV 

systems

2.8- to 3.4-kW PV; 

solar thermal water 

heating 

None 10-kW PV on one 

building; solar hot 

water heating on 

all buildings

Verification 100% 3rd party 

tested and 

inspected, all met 

federal tax credit 

criteria since 2007 

All Builders 

Challenge certified

All HERS rated All Builders 

Challenge certified

All federal tax 

credit qualified

AC = air conditioner

ACH = air changes per hour

CFL = compact fluorescent lights

Ef = energy factor

ICf = insulated concrete form

o.c. = on center wood framed walls

Pa = Pascals

PV = photovoltaic

SHGC = solar heat gain coefficient

XPS = extruded polystyrene

CS.3

BUILDING AMERICA BEST PRACTICES SERIES / CASE STUDIES

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 CS.3
Builder Fred Giacci’s decision to “raise the bar” led him into a 

collaboration with the U.S. Department of Energy’s Building America 

program that has resulted in homes with HERS scores of less than 60 

and calculated energy savings to homeowners of over $1,300 a year 

compared to the Building America Benchmark (a home built to the 

1993 Model Energy Code). Working with Building America’s Building 

Industry Research Alliance team through its local research partner 

Washington State University (WSU) Extension Energy Program, Giacci 

built 81 homes to achieve the 50% energy savings level required for the 

Federal tax credit. Although the Federal tax credit ended in December 

2009, Giacci has committed to building the remaining 31 homes in his 

230-unit Mediterranean Villas community in Pasco, Washington, to 

achieve these exceptional energy savings and he continues to look for 

ways to raise the bar even higher.

Since 1988 Giacci has built 300 homes in southeastern Washington. 

In 2002 Giacci became the first production builder in his area to use 

insulated concrete form (ICF) walls. In 2006 he committed to building 

all of his homes to qualify for Northwest ENERGY STAR. Devoted 

Builders was named a Northwest ENERGY STAR builder of the year 

in 2008-09. In 2007 Giacci helped the local home builders’ association 

start a Built Green program and since then has achieved a 3-star rating 

on all his homes (the local program does not have a 4-star level yet).

In 2006, David Hales of the WSU Extension Energy Program 

approached Giacci about working on a demonstration project for DOE’s 

Building America program. “We got involved with Giacci because he 

was the first production builder in Washington state that was taking 

advantage of the Federal tax credit. With ICF, heat recovery ventilators, 

and good windows, Devoted Builders was fairly easily qualifying for the 

tax credit,” said Hales. 

BUILDING TECHNOLOGIES PROGRAM

Devoted Builders of Kennewick, 

Washington, worked with Building 

America’s BIRA team to achieve the 50% 

Federal tax credit level energy savings 

on 81 homes at its Mediterranean Villas 

community in eastern Washington.

Building America Best Practices Series

Volume 12. Builders Challenge Guide to 40% Whole-House 

Energy Savings in the Cold and Very Cold Climates

Case Study:

Devoted Builders, LLC

Mediterranean Villas | Pasco, WA

BUILDER PROFILE

Builder: Devoted Builders, LLC

www.mvtownhomes.com

Where: Kennewick, WA

Founded: 2002

Development: Mediterranean Villas

Size: 230 homes

Square Footage: 1, 1.5, and 2-story, 

duplexes and triplexes, 2- and 3-bdrm, 

1,140 to 2,100 ft2

Price Range: $145,000 to $300,000

Energy-Efficiency Commitment: 

All Northwest ENERGY STAR since 2006, 

all Built Green since 2007

R
Energy-Efficiency Features

Devoted Builder’s exceptional energy performance starts with insulated 

concrete form wall construction. Giacci first looked at ICFs in 2002 

during the planning stages of Mediterranean Villas. “I wasn’t happy 

with sticks. I analyzed many different methods—brick, blocks, etc. 

Then I zeroed in on ICF and found a contractor who could put them 

together,” said Giacci. 

Giacci chose an ICF product consisting of 16-inch by 4-foot rigid expanded 

polystyrene (EPS) foam blocks separated at 4 or 6 inches by plastic spacers, 

which are connected to heavy plastic studs set vertically in the foam every 

6 inches. The location of these studs is marked on the outside of the 

foam blocks making it easy to locate them for screwing in drywall on the 

interior or siding on the exterior side of the finished wall. The foam blocks 

are stacked, like LegosTM, to form the home’s exterior walls. Vertical and 

horizontal rebar is set in the spacers and concrete is poured between the 

two 2 and 5/8-inch-thick layers of rigid foam to fill the gap. 

The ICF walls provide an insulation value of R-25. The exterior of the 

walls is covered with a gray coat of cement and polymer, which provides 

some waterproofing. Stucco is applied directly to the gray coat. The 

ICF foundation wall goes down into the ground 30 inches so it provides 

adequate frost protection as well as R-25 of perimeter slab insulation. 

Any ducts in the attic are mastic sealed, then the ducts and the lid of the 

ceiling deck are covered with an inch of spray foam. This is topped with 

more than a foot of blown cellulose to achieve R-49 attic insulation. 

Spray foam ceiling insulation and ICF walls have helped Giacci achieve 

very low air leakage rates of below 2.0 air changes per hour at 50 Pascals 

on all homes. All homes are blower door tested. Some are as low as 

0.8 ACH at 50 Pa. 

“The kind of building they’re 

doing has set Devoted apart 

from other builders in the area.”

David Hales, project manager, Washington 

State University Extension Energy Program, 

a Building America research partner

(left) Spray foam is used to insulate and 

air seal the “lid” or ceiling deck and any 

ducts located in the attic in Devoted 

Builders’ homes in Pasco, Washington. 

The spray foam is covered with more 

than 12 inches of blown cellulose for the 

equivalent of R-49 of attic insulation.

(right) Insulated concrete form walls 

provide superior insulating, air sealing, 

and sound proofing capabilities.

BUILDING AMERICA BEST PRACTICES SERIES

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With such low infiltration rates, fresh air must be brought in through 

intentional means to maintain healthy indoor air quality. Each home 

has an energy-recovery ventilator (ERV) to distribute tempered air 

throughout the home via small ducts located in conditioned space. 

The ERV is located either in conditioned space or in the garage.

With input from WSU, Devoted Builders transitioned from gas furnaces 

to standard heat pumps with a gas furnace backup in 2007. In 2009, 

Devoted stopped installing gas furnaces and upgraded to advanced heat 

pumps that are rated at 8.5 HSPF for heating and 14 SEER for cooling. 

The Sanyo heat pumps extract heat from the air down to 10°F; backup 

heat is provided by in-line electric resistance heaters. While this system 

can be mounted to the wall as a ductless unit, concerns about buyer 

reactions to the look of the wall-mounted inside units led Giacci to 

install the inside units in a distribution box located in conditioned space 

in a closet with a fan to distribute conditioned air through ducts, some 

of which are located in the attic. 

The homes come equipped with ENERGY STAR dishwashers and 

70% of the fixtures are hardwired with compact fluorescent lighting.

As part of its strong commitment to quality assurance, Devoted has 

100% of its homes third-party tested and inspected. Since 2007, all of 

Devoted Builder’s homes have met the Federal tax credit level of 50% 

savings over the 2004 IECC. These homes also are calculated to save 

43% over the Building America benchmark.

Anticipated future improvements include solar hot water or heat pump 

water heaters, PV-ready designs, ductless heat pumps, 100% CFLs, and 

BuiltGreen community layout, with a goal of reaching net zero energy 

homes. Because Devoted Builders is already meeting the Building 

America and the Federal tax credit savings levels, Giacci does not 

anticipate any difficulty in implementing the 2009 IECC.

Dollars and Sense

The table below compares calculated energy usage and energy savings 

for one of Devoted Builders’ house plans and the Building America 

benchmark home (a home built to the 1993 Model Energy Code). 

The usage and savings were calculated by Building America research 

partner WSU Extension Energy program. WSU calculated that the 

Devoted Builders’ home would have 25% energy savings over the 

2006 Washington State energy code and 43% energy savings over the 

Building America benchmark home. The home would save $1,333 in 

energy costs each year. After subtracting out the increased mortgage 

costs to cover the increased initial cost of the energy-efficiency 

measures, the homeowner would net $524 per year over the 30 years 

of the mortgage. 

Energy-Efficient Features 

•	 HERS scores 54-68

•	 R-25 insulated concrete form (ICF)

exterior walls

•	 R-49 blown cellulose in attic

•	 0.29 U-value windows

•	 Whole house air leakage 3.0 ACH

or less at 50 Pa

•	 Duct leakage less than 6 cfm at

50 Pa to exterior

•	 8.5-HSPF, 14-SEER heat pump with

backup 93% AFUE gas furnace

•	 70% hardwired CFL lighting

•	 ENERGY STAR refrigerator,

dishwasher, clothes washer

•	 Energy-recovery ventilator,

75% total efficiency

•	 3-star Built Green certified

•	 ENERGY STAR certified

•	 50-year, 110-mph, composition roof

(top) Every home is equipped with an 

energy-recovery ventilator to provide 

conditioned fresh air throughout the home.

3

CASE STUDY: DEVOTED BUILDERS, LLC
“We showed a positive cash flow for the homeowner from day 1. 

There is no question there is some added expense for the ICF. But the 

homeowner is coming out ahead,” said Hales. 

Devoted Builders offers a 2-year warranty on craftsmanship and 

materials and a 10-year structural warranty. Homes sell for $145,000 

to $300,000. Most homes are sold through presales.

Giacci has seen competition from builders willing to build inexpensive 

models that just meet code. Although their energy performance 

is so exceptional, Giacci markets the Mediterranean-style duplex 

condominiums based on their location, design, and ease of maintenance. 

Table 1. Added Costs and Savings of Energy-Efficient 

Measures for Devoted Builders

Total Energy Savings 54%

Total Added Builder Costs* $10,132

Annual Mortgage Payment Increase** $809

Annual Utility Savings $1,333

Annual Net Cash Flow to the Homeowner $524

*Costs are based on builder estimates, and manufacturers’ data. These costs do not reflect 

rebates, incentives, and subsidies.

**The annual mortgage payment is an estimate calculated by CARB and is based on a 30-year 

mortgage with a 7% fixed interest rate.

“We sell a lot of homes to engineers; they are all over our product. 

But the general public needs more education on the value of energy 

efficiency,” said Giacci. Giacci commented that in the Seattle and 

Denver areas, green homes sell for more and realtors are more aware 

of the differences because the multiple listing sheets list the home’s 

green and energy-efficient features, but that is not the case in 

eastern Washington. 

The Bottom Line

According to Hales, Giacci is positioning his company well for the 

future. “Energy is just going to get more expensive. Fred has always been 

open to new technologies and new ways to produce a high-performance 

home. He is very committed to the idea that it’s the right thing to do. 

He’s consistently building the highest performing homes in the state that 

I’ve seen and I expect he will continue to lead in energy-efficient home 

building,” said Hales.

For More Information

www.buildingamerica.gov 

EERE Information Center 

1-877-EERE-INF (1-877-337-3463) 

eere.energy.gov/informationcenter

PNNL-SA-76313 February 2011

BUILDING AMERICA BEST PRACTICES SERIES

4
East Liberty Development, Inc., worked with the U.S. Department of 

Energy’s Building America team lead IBACOS and builder S&A Homes 

to build six homes in Pittsburgh’s East End that achieved Home Energy 

Rating Scale (HERS) scores of 51 to 55. 

“We literally designed the house around the HVAC system,” said Eric 

Jester, a project manager with East Liberty Development, Inc.

“In standard building, the mechanical systems are an afterthought,” 

said Kevin Brozyna, an IBACOS building performance specialist. “Your 

typical builder will frame the house and then the mechanical contractor 

will figure out how to route the ductwork around the framing. From the 

start, we wanted to design an integrated solution.”

IBACOS worked with the architects Pfaffmann & Associates and Moss 

Architects to help them meet the project requirements: designs that could fit 

on narrow in-fill lots 25 to 40 feet by 110 feet deep, incorporating Building 

America-recommended energy-efficiency specifications, while using S&A 

Home’s typical procedures and material suppliers where possible. 

East Liberty Development, Inc., is a non-profit community development 

corporation focused on neighborhood renewal, whose efforts sparked 

a renaissance in this older Pittsburgh neighborhood. Now employers 

like Google, new retail stores like Whole Foods and Target, and new 

restaurants join a growing number of new homeowners and investors in 

this previously forgotten part of the city. 

“Real estate is perception. These homes give a strong perception that investing 

in East Liberty is a good idea, and people are following that cue,” said 

Jester. “We have seen a plummeting crime rate (down 60%) and an increase 

in single-family house values across the neighborhood of 100% or more.”

BUILDING TECHNOLOGIES PROGRAM

S&A Homes worked with Building 

America’s IBACOS and architects 

Pfaffmann & Associates and Moss 

Associates to design energy-efficient 

homes for urban in-fill lots. This is a new 

market for S&A Homes, which builds over 

500 homes a year using suburban designs. 

Building America Best Practices Series

Volume 12. Builders Challenge Guide to 40% Whole-House 

Energy Savings in the Cold and Very Cold Climates

Case Study:

S&A Homes

East Liberty | Pittsburgh, PA 

BUILDER PROFILE

Builder: S&A Homes

Where: State College, PA

Founded: 1980s

Employees: 150

Development: East Liberty

Size: 3 bedroom, 3 baths

Square Footage: 3,108 ft2, includes 

1,004 ft2 basement 

Price Range: $216,000 to $305,000 

R
Energy-Efficiency Features

The first step in designing the homes was to put all of the HVAC 

equipment and ductwork within the highly insulated and air-sealed 

thermal envelope. The completed homes blower door tested at 3.0 air 

changes per hour (ACH) at 50 Pascals, compared to 9 ACH at 50 Pa 

for a typical home. 

The tight building shell consists of 2x6 24-inch-on-center stud wall 

cavities filled with R-24 blown-in fiberglass. The walls are sheathed 

with 1⁄2-inch OSB and housewrap and clad with LP SmartSiding®, a 

compressed wood product impregnated with a zinc borate preservative. 

“Every single stud was air sealed. Every single penetration was air sealed 

with a low-expansion foam,” said Todd Winnor, the project manager for 

S&A Homes. Double-pane windows with a low U-value of 0.33 and a 

low SHGC of 0.30 complete the wall assembly.

The unconditioned attic contains R-49 blown-in fiberglass insulation. 

“We used raised-heel trusses to get the full depth of insulation over the 

exterior wall,” said Winnor. 

All of the HVAC equipment is located in the basement. The insulated, 

precast-concrete wall system (Superior Wall xiTM) includes 21⁄2-inch Dow®

extruded polystyrene insulation (R-12.5) within a 13⁄4-inch concrete 

exterior. This insulated wall panel comes factory-assembled with steelreinforced steel-faced concrete studs at 24 inches on center. 

“Originally, we looked at enhancing the stud cavities with an R-13 batt,” 

said Winnor, “but when we tried this with the first home, we had a very 

cold winter and got some condensation. So we ended up pulling out the 

batts, and now it works just fine.”

In the basement and first-floor ceilings, open-web floor trusses contain 

the ducts. Brozyna, the building scientist with IBACOS, notes, “The 

open-web floor trusses were not selected primarily as an energy feature, 

but they allowed us to more efficiently route the mechanical systems.” 

Two-stage, 96% AFUE natural gas-fired furnaces with a multi-speed 

blower are located in the basement. A SEER-14 system provides air 

conditioning. Fresh air is provided through a 6-inch supply-air duct 

connected to the return plenum, and a fan-cycler provides ASHRAE 

62.2 rates for fresh air at a 50% run time. The natural-gas-fired tankless 

water heater supplies heated water with a 0.82 energy-efficiency rate. 

IBACOS prepared mockups of field assemblies at its warehouse for 

hands-on training sessions for the subcontractor crews. “If they had 

any questions or suggestions for improving the process, we could work 

this out before we got into the field,” said Brozyna.

(top) In a market where the median 

house price is $100,000, East Liberty 

Development, Inc., has sold three of its 

super-energy-efficient homes at prices 

starting at $216,000.

(bottom) The HVAC equipment is located 

in conditioned space in the basement, 

which is thoroughly insulated and air 

sealed with precast concrete walls that 

come to the site with 2.5 inches of foam 

insulation and steel-reinforced insulated 

concrete studs already installed.

“Codes are improving. Trades are 

aware that things are becoming 

more strict, and they are going to 

be required to be more diligent in 

their work. Have a discussion with 

the trades to let them know what 

you expect and make sure they 

are committed to pulling it off.”

Kevin Brozyna, IBACOS

BUILDING AMERICA BEST PRACTICES SERIES

2
Community Development

East Liberty Development, Inc., bought lots in a challenged east end 

neighborhood in Pittsburgh where “gangs, absentee landlords, trash and 

drug raids stained the scenery” (Pittsburgh Post-Gazette, December 22, 

2008). The non-profit demolished blighted properties and built the six 

new Building America homes. East Liberty Development, Inc., currently 

has control of 60 properties in a 10-block area and plans to build and 

rehabilitate additional houses as these homes sell. It has committed to 

building all of its new homes to the Building America energy savings 

target of 40% or higher.

“In 2005, single-family home values in the neighborhood ranged from 

$40,000 to $50,000,” said Jester. “Our highest sale was $315,000, nearly 

630% higher.” In the first half of 2010, average prices for existing 

single-family homes in East Liberty climbed to $145,000 as prices 

dropped citywide, thanks in part to East Liberty Development, Inc.’s 

community develoment efforts.

Dollars and Sense

Building America analysis shows the estimated cost above code for 

the energy-efficient improvements to be about $9,900 per house 

(or $3.42/ft2

), assuming a 30-year loan with 7% interest (Table 1). 

However, the energy-efficiency measures can result in an annual utility 

bill savings of $1,699 compared to the Building America benchmark 

(a home built to code requirements of the mid-1990s), which results 

in a return on investment in less than 5 years.

Energy-Efficient Features 

•	 HERS 51-55

•	 2x6, 24-inch-on-center

advanced framing

•	 Wall insulation:

R-24 blown-in fiberglass

•	 Attic insulation: R-49 blown-in

fiberglass insulation

•	 Foundation insulation:

Superior Wall xiTM includes

21⁄2-inch Dow® extruded polystyrene

insulation (R-12.5)

•	 Windows: Double-pane, U = 0.33

and SHGC = 0.30

•	 Air sealing tightness: blower door

testing of 3.0 ACH at 50 Pa

•	 96%-AFUE natural gas-fired furnace

with a multi-speed blower

•	 14-SEER cooling system

•	 0.82 EF (energy factor) tankless

gas-fired hot water heater

•	 Ducts in conditioned space

•	 100% CFL lighting

•	 ENERGY STAR appliances

High-performance windows and 100%

fluorescent lighting add to the energy 

savings in these craftsman-style homes.

East Liberty Development, Inc., uses a modified Builders Challenge label 

in its marketing efforts.

3

CASE STUDY: S&A HOMES
Table 1. Added Costs and Savings of Energy-Efficient 

Measures for S&A Homes

Total Energy Savings 49%

Total Added Builder Costs* $9,419

Annual Mortgage Payment Increase** $752

Annual Utility Savings $1,651

Annual Net Cash Flow to the Homeowner $899

*Costs are based on builder estimates, RS Means, DEER, and manufacturers’ data. These costs 

do not reflect rebates, incentives, and subsidies.

**The annual mortgage payment is an estimate calculated by CARB for comparison purposes 

and is based on a 30-year mortgage with a 7% fixed interest rate and a 10% builder markup over 

added first cost.

Overcoming Challenges

Training the subs was difficult,” said Winnor. “We have subcontractors 

who have been doing things the same way for 20 years, and they 

needed to start thinking differently about this. Every single person 

building the house, even the painter, plays a role in energy efficiency.”

IBACOS took an active role in subcontractor training by preparing 

mockups of field assemblies at its warehouse and providing hands-on 

training sessions. “We had the actual crew, who would be performing 

the work in the field, come to participate in the build-outs at the 

mockup site [for learning and practicing]. If they had any questions or 

suggestions for improving the process, we tried to work this out before 

we got into the field,” said Brozyna.

“My advice to other builders,” says Winnor, “is to take it slow. Get your 

best subcontractors and get them involved early in the process because 

you want their feedback. Create partnerships with them to move forward. 

Make sure it is a guy who will be around awhile because you are making a 

huge investment in your subcontractors when you do something like this.”

The Bottom Line

“My experience working with the Building America program has been 

a great one. I have learned more things about energy efficiency in a 

year than a typical home builder would in several years. This project 

has provided us a road map to achieve the high-performance house of 

today and the net-zero energy home of tomorrow,” said Winnor. 

And tomorrow is now. S&A Homes is working with IBACOS to build 

a “lab home” that tests the materials and construction practices needed 

to reach net-zero energy in a cold climate. “The lab house pushes us 

even further into tomorrow so we understand now what we need to do 

for 10 to 15 years ahead when the code changes,” said Winnor.

For More Information

www.buildingamerica.gov 

EERE Information Center 

1-877-EERE-INF (1-877-337-3463) 

eere.energy.gov/informationcenter

PNNL-SA-76316 February 2011

BUILDING AMERICA BEST PRACTICES SERIES

4
Nelson Construction, the first builder to work with Building America 

in Connecticut, built 10 homes that received the U.S. Department of 

Energy’s Builders Challenge certification. All 10 homes achieved energy 

savings of 50% over the Building America benchmark. 

“We have been an ENERGY STAR builder as long as it has been 

around, and we wanted to push the limits for energy efficiency,” said 

Chris Nelson, president of Nelson Construction. “Teaming up with 

Building Science Corporation through Building America gave us the 

confidence to push way beyond what we might have tried on our own.”

Nelson Construction partnered with Building America’s research team 

lead Building Science Corporation on the energy-efficiency design and 

analysis of the 10 homes located in the Hamilton Way development 

that Nelson built with Landworks Realty in Farmington, just outside of 

Hartford, Connecticut. Selling prices started at $649,000. Each home 

has two stories (ranging from 2,960 to 3,540 square feet), four bedrooms, 

31⁄2 to 41⁄2 baths, and heated basements (for an additional 1,404 to 1,653 

square feet). 

Energy-Efficient Features

“Our first step is to do as much as we can [to achieve energy savings] for 

zero cost to the builder,” said Peter Baker, a senior associate with BSC 

who worked with Armin Rudd, a principal at BSC, on this project.

Design-stage computer analysis estimated that 18.5% of the energyefficiency savings could be achieved by reducing air infiltration. 

“Chris Nelson is a very conscientious, high-quality builder,” said Baker. 

“Previously, he was doing a full flash- and-batt approach, which involves 

using a thin layer of spray foam in all of the wall cavities.” 

BUILDING TECHNOLOGIES PROGRAM

Building America’s research team lead 

Building Science Corporation helped 

Nelson Construction achieve HERS 

scores of 53 and 54 on ten homes in 

Farmington, Connecticut.

Building America Best Practices Series

Volume 12. Builders Challenge Guide to 40% Whole-House 

Energy Savings in the Cold and Very Cold Climates

Case Study:

Nelson Construction

Hamilton Way | Farmington, CT 

BUILDER PROFILE

Builder: Nelson Construction

www.nelsonconstructionct.com

Where: Farmington, CT

Founded: 1992

Employees: 12

Development: Hamilton Way

Construction Date: 2007–2009

Size: 10 two-story single-family homes, 

2,960–3,540 ft2

Price Range: $650,000+ (all 10 homes 

sold within 2 months of being listed) 

R
Building America research showed minimal difference between spray 

foaming the entire opaque surface of a wall and simply spray foaming 

insulation into areas known for leaks. The team used this “critical seal” 

approach for reducing air infiltration and saving money. Urethane 

closed-cell foam was sprayed into the air gaps at the basement rim 

joists, at the rim joists between the first and second floors, around 

windows, and at any mechanical/electrical penetrations. Air tightness 

targets were set at 3.0 air changes per hour, and all of the homes tested 

approximately 25% below the target. The only place where full coverage 

was used was in the ceiling of the garage to ensure no potential air 

leakage to the living space above.

Building America analysis estimated 11.5% of the energy savings were 

possible through increased insulation. Nelson filled his 2x6 24-inch 

on-center wood stud wall cavities with R-19 damp-spray cellulose cavity 

insulation, and sheathed the walls with two inches (R-13) of foil-faced 

polyisocyanurate insulating sheathing, Tyvek wrap, and vinyl siding. 

The vented attic has R-50 blown-in fiberglass insulation. Two inches 

of R-10 extruded polystyrene foam (XPS) is under the foundation slab. 

The basement walls use a Thermomass® System, consisting of 2 inches 

of XPS sandwiched between two 4-inch layers of concrete.

The improved thermal boundary (insulation and air barrier) enabled the 

team to downsize the HVAC system from two air handlers (one in the 

attic and one in the basement) to one in the basement that uses zonecontrol dampers for the first floor/basement and second floor. The first 

and second floors each contain one ducted return with jump ducts at 

the bedrooms. 

Heat is supplied by a 94% AFUE sealed-combustion gas furnace. The 

14 SEER air conditioner was downsized from 4.5 or 5.0 tons to 3.0 or 

3.5 tons. “What we are hearing from the homeowners is that the systems 

are working great and very comfortable,” said Baker. 

Domestic hot water is provided by a 0.82-efficiency factor instantaneous 

gas water heater. The homes are 100% hardwired for CFLs.

To date, Nelson Construction has less than a year of utility data for the 

homes, but the data so far indicate that the homes are consuming 50% 

less energy than the Building America benchmark, a house built to the 

1993 Model Energy Code. The homes achieved Home Energy Rating 

System (HERS) scores of 53 and 54.

Nelson offered a photovoltaic option, and three homeowners chose the 

7-kW photovoltaic systems. “They are making way more energy than 

they are using. They are 8 months into the year, and they are so far 

ahead of the utility company that they will not pay utility bills this 

year other than service charges,” Nelson said.

“Teaming with Building America 

is a great marketing tool because 

we can honestly say we are 

building houses better. The HERS 

certificate from the DOE proves it.”

Chris Nelson, president, Nelson Construction

(top) All lights were hard-wired for CFLs. 

(middle) Sprayed urethane closed-cell 

foam provided a critical seal along floor 

joists separating the garage from the 

living space above. Further insulation was 

provided by unfaced batt. 

(bottom) Nelson Construction sealed the 

rim joists with spray foam to air seal and 

insulate from foundation wall to subfloor.

BUILDING AMERICA BEST PRACTICES SERIES

2
Health, Durability, Sustainability

With such air-tight construction, it was essential to design in ventilation. 

The team decided on a semi-balanced approach using a controlled fresh 

air intake with exhaust fans. For supply ventilation, an Aprilaire VCS 

8126 brings outside air into the home through a duct to the return side 

of the air handler. A flow regulator provides fixed outside air-supply 

quantities independent of air-handler blower speed, and the HVAC 

system provides circulation and tempering. Stale air is exhausted through 

a fan in an upstairs bathroom. This 1-sone-rated fan is connected to the 

main space with a 6-inch jump duct. The laundry room has a transfer 

grille installed to provide pressure relief during dryer operation. 

The supply system is sized to meet ASHRAE 62.2 ventilation rates. To 

avoid the potential for cold air complaints when the fan blows without 

the furnace firing, BSC recommends that not more than 125 cubic feet 

per minute (CFM) be supplied per register in bedrooms and not more 

than 500 CFM be supplied per register in other rooms. To achieve this, 

an 8-inch to 10-inch supply duct to the master bedroom should be 

split into two 6-inch or 7-inch supply ducts. Homeowners should be 

educated to keep their winter thermostat set points at 70oF or above.

Dollars and Sense

Hamilton Way experienced a high volume of sales in a market where 

sales had almost completely stopped. All 10 Builders Challenge homes 

in the development sold within 2 months of completion.

“It only costs about $18,000 extra per house [to make the energy-efficient 

upgrades]. That is about 4% [of the sales price] to achieve about $250 a 

month in energy savings,” said Nelson. “If you take the added mortgage 

on $18,000 at 5% interest, it is costing you $80 to $90 a month, but you 

are saving $250 a month in utility costs.”

Energy-Efficient Features 

•	 HERS scores 53-54

•	 24-inch-on-center advanced framing

of 2x6 studs

•	 Wall insulation: 2-inch foil-faced

polyisocyanurate sheathing (R-13) and 

stud cavities filled with R-19 cellulose

•	 Attic insulation: R-50 blown fiberglass

•	 Foundation insulation: R-10 2-inch

extruded polystyrene foam (XPS) 

below slab; R-10 2-inch XPS cast in 

walls (Thermomass)

•	 Windows: Double-glazed, lowemissivity, argon-filled, vinyl-framed; 

U = 0.32, SHGC = 0.27

•	 Air sealing tightness: infiltration of 3.0

to 3.3 air changes per hour (ACH) at 

50 pascals

•	 94% AFUE sealed-combustion gas furnace

•	 14 SEER air conditioner

•	 0.82 EF (energy factor) instantaneous

gas hot water heater

•	 Ducts in conditioned space with less

than 5% leakage (R-6 flex runouts in

dropped ceiling or in floor joists)

•	 100% hardwired CFL lighting

(left) The basement walls use a Thermomass® 

system, which is 2 inches of extruded polystyrene 

foam sandwiched between 4 inches of concrete.

(right) In this heating-dominated climate, the 

94% AFUE sealed-combustion gas furnace

helps ensure enough heat on the coldest days.

3

CASE STUDY: NELSON CONSTRUCTION
The largest single cost upgrade resulted from the two inches (R-13) of 

foil-faced polyisocyanurate insulating sheathing at a cost of $10,000 

per home. The approximate incremental cost per square foot of all 

energy upgrades was $6.97.

Building America analysis predicted between $2,429 and $3,447 

annual utility savings compared to the Building America benchmark, 

depending on the house plan. When the annual mortgage increase is 

subtracted from the savings, results still yield a positive cash flow to 

homeowners of $1,392 per year for the building (see Table 1). 

Table 1. Added Costs and Savings of Energy-Efficient 

Measures for Nelson Construction

Energy Savings vs Benchmark 48%

Annual Mortgage Payment Increase (without PV)* $2,055

Annual Utility Savings $3,447

Annual Net Cash Flow to the Homeowner $1,392

*The annual mortgage payment is an estimate calculated by BSC and is based on a 30-year 

mortgage with a 7% fixed interest rate.

The Bottom Line

“This experience has definitely helped us raise the bar on all the houses 

we build. It has become part of our company identity that we build 

energy-efficient, healthy, sustainable homes,” Nelson added. “Now we 

have a marketing advantage. We are looked at as one of the experts in 

the industry related to energy efficiency. From a developer’s side, it helps 

us get approvals, which is really a big deal and nothing we were thinking 

about when we decided to do this. Towns want to work with builders 

who are doing things better.”

For More Information

www.buildingamerica.gov 

EERE Information Center 

1-877-EERE-INF (1-877-337-3463) 

eere.energy.gov/informationcenter

PNNL-SA-76314 February 2011

“We sold all the homes in less 

than two months. The people who 

were buying our homes wanted 

to buy something that was 

built better.”

Chris Nelson, president, Nelson Construction

Each of the 10 DOE Builders Challenge

homes sold within 2 months of completion.

BUILDING AMERICA BEST PRACTICES SERIES

4
Wisdom Way Solar Village is an appropriate moniker for the 20-unit 

community of energy-efficient duplexes in Greenfield, Massachusetts. 

The homes meet the requirements of the U.S. Department of Energy’s 

Builders Challenge, achieving HERS scores of 8 to 18 by packing 

energy-efficiency features into the compact, heavily insulated homes 

and adding solar water heating and photovoltaics on top, to net home 

owners energy cost savings of at least $2,500 per year per home.

The homes are so well insulated, a small (10,000 to 16,000 Btu) gas-fired 

space heater is all that is needed to heat them. Most homeowners are 

spending less than $500 per year for natural gas. The space heaters cost 

builders about $5,000 less per unit than a typical central gas or electric 

furnace. 

The homes were built by Rural Development Incorporated (RDI), a 

non-profit organization focused on energy-efficient, affordable housing 

in western Massachusetts. The Consortium for Advanced Residential 

Buildings (CARB), a U.S. Department of Energy Building America 

research team led by Steven Winter Associates, provided design 

assistance and analysis on the project.

CARB’s preliminary analysis of utility bills showed most homeowners 

getting credits from the electric utility throughout the winter months 

thanks to the combination of energy-saving features and electricityproducing photovoltaic panels. “Homeowners are thrilled with their 

negative electric bills,” said Robb Aldrich, an engineer with CARB. “If 

you can get the building shell this well insulated, you are going to see 

significant heating energy savings, almost regardless of what heating 

system you choose,” Aldrich noted.

BUILDING TECHNOLOGIES PROGRAM

The 20 duplexes built by Rural 

Development, Inc., in Greenfield, 

Massachusetts, with help from 

Building America’s CARB team 

have HERS scores of 8 to 18.

Building America Best Practices Series

Volume 12. Builders Challenge Guide to 40% Whole-House 

Energy Savings in the Cold and Very Cold Climates

Case Study:

Rural Development, Inc.

Wisdom Way Solar Village | Greenfield, MA

BUILDER PROFILE

Builder: Rural Development, Inc.

www.ruraldevelopment.org

Where: Greenfield, MA

Founded: 1991

Employees: 6

Development: 

Wisdom Way Solar Village

Size: 20 homes in 10 duplexes

Square Footage: 1,140-1,770 sq. ft. 

Price Range: $110,000 (subsidized) 

to $240,000

Energy-Efficiency Commitment: 

Better than 50% energy savings

R

1
Energy-Efficient Features

A unique feature of the homes is their double-walled construction. 

The exterior 2x4 16-inch-on-center framed wall is built first; it is 

sheathed on the exterior side with OSB, but no interior gypsum. Then 

the second 2x4 framed wall is built inside with a 5-inch gap between 

the two walls. A mesh liner is stapled to the inner wall’s studs to form 

a 12-inch-deep cavity between the two walls. The cavity is filled with 

dense-pack dry-blown cellulose insulation at 3.4 pounds per cubic foot 

density for an R value of 42, with no thermal bridging. RDI employs its 

own carpentry staff and uses a basic rectangle-shaped house design to 

decrease complications with this nonstandard framing. CARB visited 

the site at least once a month during construction and provided training 

to the trades. Blower door tests by a third-party inspector found air 

leakage to be 200–350 cfm or 1 to 1.5 air changes per hour at 50 Pascals. 

The vented attic incorporates ridge and soffit vents with baffles at 

every truss bay to minimize disturbance to the 14 inches of loose 

blown cellulose, which provides R-50 attic insulation. The homes 

have full, unconditioned basements. Although CARB would typically 

recommend insulating the basement walls, in this case RDI chose to 

insulate under the floor joists with R-40 of blown cellulose held in place 

with vapor-permeable mesh stapled to the I joists, after energy modeling 

showed that 3 inches of rigid insulation would have been needed to get 

the same performance, and at considerably higher cost because the local 

building department would have required that gypsum be installed to 

cover the foam due to flamability.

Because the homes are so well insulated and have compact designs 

(1,137 ft2

 to 1,773 ft2), RDI was able to meet the design heat load 

of 12,000 Btu per hour with a space heater. RDI chose a sealedcombustion, natural gas-fired heater that was placed in the living room 

on the homes’ first floor. The heater has a capacity of 10,200 Btu per 

hour on low fire and 16,000 Btu per hour on high fire with an annualized 

fuel utilization efficiency (AFUE) of 83%. In previous projects, RDI had 

used hydronic baseboard heating with a gas or oil boiler. By installing 

the space heater instead, RDI saved about $5,000 per home. Because the 

units are sealed combustion with piping directly to the outside to bring 

in combustion air and send out flue exhaust fumes, there is little danger 

of backdrafting.

There is no traditional duct system with this type of space heater. 

Instead, CARB suggested putting an exhaust fan in the living room 

ceiling above the space heater. In winter the fan “exhausts” warm air 

into each of the upstairs bedrooms through PVC “ducts” connecting the 

fan to duct registers located 1 foot above the floor on the inside wall of 

each room. CARB measured the air flow at each register and found the 

flow to be fairly evenly distributed at 20 to 30 CFM per outlet. CARB 

(top) The double-stud wall consists of 

two 2x4 16-inch-on-center framed walls 

set 5 inches apart. 

(bottom) A vapor-permeable mesh is 

stapled to the inside surface of the inside 

wall forming a 12-inch-deep cavity to hold 

R-42 of dry-blown cellulose insulation.

With a better thermal envelope, 

builders can offer homeowners 

“protection” from high fuel bills.

BUILDING AMERICA BEST PRACTICES SERIES

2
also found temperatures were very consistent from room to room when 

occupants followed CARB’s recommendations to leave the thermostat at 

one temperature with no day/night setbacks. 

For north, east, and west-facing windows, RDI selected a triple-pane 

window with low-emissivity coatings on the second and fifth surfaces, 

a U-value of 0.18, and an SHGC of 0.23. To save costs and increase 

desired solar gain, on south-facing windows, RDI installed a doublepane window with a U-value of 0.26, an SHGC of 0.37, and a lowemissivity coating on the third (inside) surface. 

RDI installed a 2.8- or 3.4-kW photovoltaic system on the roof of each 

home. In the first 6 months of occupancy (Nov. 2009 – April 2010) 

most of the homeowners reported negative electric bills. Water heating 

is provided by flat-plate solar thermal collectors with gas-fired tankless 

water heaters for backup. 

Dollars and Sense

CARB collected natural gas billing data for four of the homes for 

November through April 2010 and found that natural gas bills totaled 

$242 to $354/home for the 6 months, or $40 to $59/month (for the 

space heater, a gas clothes dryer, a backup on-demand gas water heater, 

a cook stove with oven, and monthly service charges). This is about 

one-fourth the $1,930 average annual oil heating bill in New England 

based on 2005 data from the U.S. Energy Information Administration. 

The energy-efficient gas heater offers a stable alternative to heating 

with oil, which has seen erratic prices over the past two years, ranging 

from $2.50 to $4.50/gallon. 

As shown in Table 1, CARB estimated that RDI spent about $11,800 

more to add energy-efficiency features compared to a house built to 

the Building America benchmark. The largest expense was $9,750 to 

purchase and install the solar water heating system. RDI saved $5,000 

per unit by replacing a gas or oil boiler and radiators with the ductless 

gas-fired space heater. CARB calculated the annual increased mortgage 

cost to cover these expenses at $1,050 per year, assuming a 30-year 

mortgage at 7%. The annual utility savings was calculated at $2,192, 

yielding a net gain to the homeowner each year of $1,142. 

The photovoltaic panels are not included in the builder costs on Table 

1. They would have cost $25,000 to purchase and install at market rate; 

however, RDI got state, federal, and local grants to cut the costs. If the 

solar electricity benefit were included in Table 1, the 3.4-kW systems 

would generate $635–$700 worth of electricity per year at $0.17/kWh 

and the 2.8-kW systems would generate about $525 to $575 annually. 

Energy-Efficient Features 

•	 Foundation: Full basement with

R-40 dense-blown cellulose under 

first floor

•	 Walls: 12-inch double 2x4 wall with

R-42 dense blown cellulose

•	 Attics: Vented attic with R-50+ loose

blown cellulose

•	 Windows: East, north, and west:

vinyl-framed, triple-pane, U = 0.18, 

SHGC = 0.23. South: double-pane,

U = 0.26, SHGC = 0.37

•	 Doors: 0.20

•	 Infiltration: 200-350 cfm at 50 Pa,

based on blower-door test

•	 Heating System: Small

(10,200/16,000 Btu) space heater 

located in main living area; sealedcombustion gas-fired 83% AFUE

(Monitor Products model GF1800)

•	 Cooling System: None

•	 Water Heater: Solar thermal system

with tankless gas auxiliary

•	 ENERGY STAR Appliances:

Refrigerators and dishwashers; 

100% hard-wired fluorescent lights

•	 Ventilation: Continuous exhaust fan 

with variable-speed motor

3

CASE STUDY: RURAL DEVELOPMENT, INC.
The 20 two, three, and four-bedroom houses were offered at $110,000 

(subsidized) to $240,000 (market rate) to buyers who qualified at 

different income levels. As of August 2010, all but the five homes still 

under construction had sold.

The Bottom Line

RDI has been building ever more energy-efficient homes for low- and 

moderate-income buyers since building its first ENERGY STAR homes 

in the year 2000. Anne Perkins, RDI’s director of home ownership 

programs, noted that RDI has worked with Building America through 

its CARB team since 2006 when CARB’s Robb Aldrich assisted RDI 

with development of a prototype solar home in Colrain, Massachusetts. 

That home achieved a HERS score of 21. The homes at Wisdom Way 

received HERS scores of 8 to 18. 

“RDI could not have advanced to build near zero net energy homes 

without the design training and technical support it received from the 

CARB team led by Steven Winter Associates and DOE’s Building 

America,” said Perkins of the Wisdom Way project. “The technical 

information, the drawings, the modeling and monitoring made 

it possible.”

For More Information

www.buildingamerica.gov 

EERE Information Center 

1-877-EERE-INF (1-877-337-3463) 

eere.energy.gov/informationcenter

PNNL-SA-76315 February 2011

Table 1. Added Costs and Savings of Energy-Efficient 

Measures for Rural Development, Inc.

Total Energy Savings 56.5%

Total Added Builder Costs* $11,844

Annual Mortgage Payment Increase** $1,050

Annual Utility Savings $2,192

Annual Net Cash Flow to the Homeowners $1,142

*Costs are based on builder estimates, and manufacturers’ data. These costs do not reflect 

rebates, incentives, and subsidies.

**The annual mortgage payment is an estimate calculated by CARB for comparison purposes 

and is based on a 30-year mortgage with a 7% interest rate.

The homes are so well insulated that a 

10,200-Btu gas-fired space heater on the 

main floor, (shown in wood cabinet in top 

photo and alone in bottom photo), 

provides all the heat needed.

“This project shows that, with a 

highly efficient envelope, simple, 

low-cost space-heating systems 

can provide an affordable, 

efficient method for heating 

homes, even in a cold climate. 

Robb Aldrich, 

DOE’s CARB Building America Team 

BUILDING AMERICA BEST PRACTICES SERIES

4
Aspen, Colorado’s winter wonderland setting has attracted myriads 

of the rich and famous, but the town’s resort home prices have made 

subsidized housing a necessity for most of the working class families of 

the community. Over the past 30 years, the City of Aspen has organized 

dozens of affordable housing projects. In 2007, Aspen completed Phase 

1 of its largest and most energy-efficient project to date, the Burlingame 

Ranch community, where it has achieved Home Energy Rating System 

(HERS) scores of 54 to 62 on 84 condominium units, with assistance 

from the U.S. Department of Energy’s research team lead Building 

Science Corporation and the National Renewable Energy Laboratory.

To make homes that are truly affordable, the city has increasingly 

encouraged energy-efficient home construction. In 2004, the city took 

bids to design Phase 1 of Burlingame Ranch, an affordable housing 

development that will eventually number 258 units. For Phase 1 the city 

selected Shaw Builders of Grand Junction, Colorado, and the design 

team of Bill Poss Architects and DHM Design. The city also asked the 

Building Science Corporation to participate. 

BSC helped design the project’s energy-efficiency measures and solar 

hot water and heating systems, and reviewed energy code compliance 

reports. In 2007, BSC worked with DOE’s National Renewal Energy 

Laboratory to conduct field testing of the mechanical, solar, and 

ventilation systems and short- and long-term monitoring of one of the 

buildings before and after homeowners moved in. 

In Phase 1, all 84 homes met the Federal Tax Credit goal of 50% savings 

over the 2004 International Energy Conservation Code (IECC) and 

the Building America target of 40% savings over the Building America 

benchmark (a home built to the 1993 Model Energy Code). 

BUILDING TECHNOLOGIES PROGRAM

Shaw Construction built 84 energyefficient, affordable condominiums for 

the City of Aspen that achieved HERS 

scores of less than 62 with help from 

Building America’s research team lead 

Building Science Corporation. 

(Photo Source: Shaw Construction) 

Building America Best Practices Series

Volume 12. Builders Challenge Guide to 40% Whole-House 

Energy Savings in the Cold and Very Cold Climates

Case Study:

Shaw Construction

Burlingame Ranch Phase 1 | Aspen, CO 

BUILDER PROFILE

Builder: Shaw Construction 

www.shawconstruction.net

Where: Aspen, CO

Founded: 1962

Development: Burlingame Ranch

Construction Dates: 2005–2007

Size: Phase 1: 84 units in 15 multi-family 

buildings. Total build out: 248 units in 

30 multi-family buildings plus 10 singlefamily homes: one- and two-story, 1-, 2-, 

or 3-bedroom, avg. 1,325 ft2

Price Range: Subsidized housing 

R
Energy-Efficiency Features

Energy-saving features include a spray-foamed building envelope for 

excellent air tightness and thermal performance. The 2x6 24-inch-oncenter advanced framed walls were filled with high-density spray foam 

insulation to R-24. The unvented attics were spray foamed with R-50 

worth of insulation in cathedralized roof sections and R-38 under flat 

roof sections. 

The edges of the slab foundation were covered with R-13 of XPS rigid 

foam insulation. Some units had walk-out basements insulated with 

R-13 (2 inches) of polyisocyanurate on the interior of the basement 

walls. Basement floors were insulated to R-28 with 4 inches of highdensity, closed-cell spray foam that was sprayed directly onto the 4-inch 

layer of gravel under the foundation slab; this foam served as a vapor 

barrier as well. 

The one- and two-story units were clustered in buildings containing 

two, four, six, or eight units per building. Each building has a central 

mechanical room containing two 93% AFUE condensing gas-fired 

boilers to provide hot water for the hydronic baseboard heating systems 

as well as domestic hot water. The domestic hot water is preheated from 

a solar hot-water system consisting of 192 ft2

 of solar panels mounted 

on the roof of each building with a 120-gallon storage tank located in 

the mechanical room. 

In Phase 2, the City will request individual water- and space-heating 

systems, said Steve Bossart, project manager of the City’s capital assets 

department, because the City believes that individual furnaces and water 

heaters provide more incentive for individuals to conserve water and 

energy, and reduce homeowner association maintenance of the complex 

central systems. For Phase 2, the City is considering gas furnaces or 

electric baseboard heating. Because the building enclosures are so 

efficient, large furnaces are not needed. The City is also considering 

individual solar hot-water heating.

Ventilation is provided with continuous heat-recovery ventilators 

(HRVs) in each unit. There is no installed cooling system. Windows are 

low-emissivity, double-glazed, and fiberglass-framed. ENERGY STAR 

compact fluorescent lamps provide 90% of the lighting and units come 

with ENERGY STAR dishwashers, refrigerators, clothes washers, and 

ceiling fans installed. A passive radon-protection system is installed.

Each dwelling unit was tested for whole house air leakage by a thirdparty tester (Lightly Treading Inc. Energy & Design of Denver, who 

also did the ENERGY STAR rating certifications). Infiltration was 

found to be 2.5 in.2

 leakage area per 100 ft2 of envelope.

(top) Deep overhangs and deciduous trees 

provide shade from intense Colorado sun. 

Low-maintenance exterior materials like 

cement siding and composite decking 

are specified. (Photo Source: Ed Hancock, 

National Renewable Energy Laboratory)

(bottom) Even snow cover and lack of 

icicles show the roofs are well insulated 

with little air leakage from the sealed 

attics. Two layers of ice and water shield 

are used for ice dam protection. 

(Photo Source: Shaw Construction) 

Building in Snow Country

•	 Reduce the need to move or store

snow. Face entrances, driveways, 

and walkways to south. 

•	 Don’t locate balconies, stairs,

parking, or entrances at eaves.

•	 Design to avoid ice dams – use two

layers of ice and water shield on roof. 

Place any roof penetrations high 

toward the ridge. Air seal well. 

•	 Avoid electric snowmelt systems

and gutters. 

•	 Protect entrances under overhangs

or gable ends. 

•	 Use evergreens for windbreaks and

direct drifting away from entrances.

•	 Use low-maintenance, high-durability

exterior cladding, decking, and roofing.

BUILDING AMERICA BEST PRACTICES SERIES

2
One building was outfitted with a roof-mounted 10-kW photovoltaic 

panel array for electricity production.

Bossart noted that in Colorado, pounding sun and heavy snow loads can 

take a toll on building materials. “Our area has extreme sun exposure 

year round. Anything we can do to specify low-maintenance exterior 

materials saves time, money, and manpower for the owners. Also, 

shielding western exposures from intense afternoon sun is important,” 

said Bossart.

The builder on Phase 1, Shaw Construction of Grand Junction, 

Colorado, took an especially proactive approach in developing a 

“sustainable culture” on the Burlingame project. Rock crushers were 

set up to crush rock onsite to use for backfill, rip rap, and gabion basket 

retaining walls. Long-lasting and sustainable building products were 

installed including bamboo flooring, wool carpet, Forest Stewardship 

Council (FSC) wood, finger-jointed studs, cement siding, metal roofs 

or 50-year shingles, fiberglass-framed windows, corn-based closed-cell 

insulation, prefabricated roof trusses, and offsite panelization of wood 

framed walls. Shaw used native grasses for landscaping and a planted, 

open-ditch concept for water runoff control. Shaw made a concerted 

effort to use local materials like local cement and drywall, and standing 

dead wood for columns. 

“This project did not simply use sustainable products, everything about 

this project is sustainable. From the time workers carpooled in each 

morning to the time the workers cleaned up their work areas and put 

their trash into segregated recycle containers at the end of the day, the 

workers helped this project be “sustainable” in every way,” said David 

Hall, project manager for Shaw Construction. 

Dollars and Sense

Because homes in Aspen are so expensive, demand for the affordable 

homes at Burlingame Ranch was very high, with up to 30 applications 

for every unit. All of the units were sold before completion with buyers 

chosen by lottery. “The city sponsors these subsidized projects to 

sustain a professional working class in the city limits,” said Bossart. 

Projects are funded via a real estate transfer tax or bonds. 

Building Science Corporation calculated the added costs of building 

to the designed level of 51% more efficient than a home built to the 

Building America benchmark (a home built to the 1993 MEC). For 

one unit the added cost was approximately $6,180 in upfront costs, 

with almost half of this coming from the solar hot water system 

(see Table 1 below). 

Energy-Efficient Features 

•	 51% energy savings over Building

America benchmark

•	 Estimated cost savings $775 per unit

•	 R-50 high-density foam at sloped

roof, R-38 at flat roofs 

•	 2x6, 24-inch on-center advanced

frame stud walls with 3.5 inches 

of high-density spray-foam cavity 

insulation (R-24)

•	 Slab insulation with 2 in. XPS

perimeter insulation extending 2 ft 

below grade

•	 Milgard fiberglass-framed, doublepane windows, U = 0.37, SHGC = 0.33

•	 10-kW PV system (on one building)

•	 Roof-mounted solar thermal panels

for domestic hot water (on all 

buildings)

•	 3rd party whole-house air-leakage 

testing of every unit. Infiltration 

averaged 2.5 in.2 leakage area per 

100 ft2 envelope

•	 93% AFUE condensing boiler in

conditioned space

•	 Heat-recovery ventilator

•	 90% hard-wired fluorescent lighting

•	 ENERGY STAR dishwasher,

refrigerator, clothes washer, 

ceiling fans

•	 Water-conserving faucets,

showerheads, and toilet

“Superior enclosures with heatrecovery ventilation have allowed 

us to reduce heating costs and 

maintain indoor air quality.” 

Steve Bossart, City of Aspen

3

CASE STUDY: SHAW CONSTRUCTION
When these costs are spread over a 30-year fixed-rate mortgage at 7% 

interest, the increased annual mortgage cost is $498. The measures 

incorporated in the homes to achieve the 51% savings would provide 

$775 per year per unit in utility cost savings, based on local electricity 

and natural gas prices, which are relatively low. When the annual 

mortgage increase is subtracted from this, results still yield a positive 

cash flow to homeowners of $277 per unit.

The Bottom Line

“This project was a great model for us and has helped promote energyefficient construction to all of our employees and clients. Staying at the 

forefront of energy-efficient construction helps keep Shaw ahead of our 

competition. It differentiates us from the pack,” said David Hall, project 

manager for Shaw Construction.

For More Information

www.buildingamerica.gov 

EERE Information Center 

1-877-EERE-INF (1-877-337-3463) 

eere.energy.gov/informationcenter

PNNL-SA-76317 February 2011

Table 1. Added Costs and Savings of Energy-Efficient 

Measures for Shaw Construction

Total Energy Savings 51%

Total Added Builder Costs (per unit)* $6,178

Annual Mortgage Payment Increase** $498

Annual Utility Savings $775

Annual Net Cash Flow to Homeowner $277

*Costs are based on builder estimates, RS Means, DEER, and manufacturers’ data. 

These costs do not reflect rebates, incentives, and subsidies. Costs assume a 10% builder markup. 

**The annual mortgage payment is an estimate based on a 30-year mortgage with a 7% fixed 

interest rate. 

Solar water heating panels were mounted 

on each multifamily building to provide 

domestic hot water and pre-heat water 

for the hydronic baseboard space 

heating system.

BUILDING AMERICA BEST PRACTICES SERIES

4
Appendix I.

Homebuyer’s Checklist

Homebuyers, take this with you when you go house 

shopping to make sure you get an energy-efficient home.

MEASURE Building America

Recommendations

Builder

#1

Builder

#2

Builder

#3

HEATING AND COOLING EQUIPMENT

ENERGY STAR qualified air conditioning of SEER* 13 or greater Yes

ENERGY STAR qualified heat pump Yes

ENERGY STAR qualified boiler Yes

ENERGY STAR qualified sealed combustion gas furnace 

of 90 AFUE* or higher Yes

ENERGY STAR qualified programmable thermostat Yes

Ductwork sealed with mastic (no duct tape) Yes

5% or less duct leakage found with pressure test 

10% allowed if all ducts are located in the conditioned space. Yes

Duct Insulation: R-4 in conditioned space, R-8 in attic, R-6 in crawlspace Yes

House plans show duct layouts Yes

Ducts located in conditioned space Yes

Ducts sized according to industry standards in Manual D Yes

Heating and cooling equipment sized according to industry standards 

in Manual J Yes

House pressure balanced with jump ducts or transfer grills Yes

HVAC* equipment and duct work inspected and tested after installation Yes

Filter with MERV rating of 8 or higher installed on the central air handler Yes

Air handler isolated from garage by a thermal barrier (insulation) 

and air barrier (e.g., drywall sealed at seams) Yes

A1.1

BUILDING AMERICA BEST PRACTICES SERIES / APPENDIX I

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 A1.1
MEASURE Building America

Recommendations

Builder

#1

Builder

#2

Builder

#3

INSULATION (take a look at a house under construction before sheetrock is installed)

Insulation installed behind tubs, landings, and other hard to reach places Yes

Insulation fills entire cavities—no voids or compressed batts—

Attic insulation level without gaps and covers entire attic floor Yes

Where fiberglass batt insulation is used it is high-density Yes

Rim joists are insulated Yes

Rigid foam insulation applied under exterior siding or stucco Yes

WINDOWS (take a look at a house under construction before exterior siding is installed)

ENERGY STAR qualified windows, doors, and skylights Yes

Windows flashed to help repel water Yes

Windows rated to U-factor of 0.40 or less and SHGC of 0.40 or less Yes

MOISTURE MANAGEMENT (take a look at a house under construction before exterior siding is installed)

Ground slopes away from house Yes

Housewrap, building paper, or rigid foam exterior insulation, taped at 

seams and caulked at edges, covers OSB walls in wood-framed houses Yes

Roof flashing in valleys, where walls and roofs intersect, and at other 

places where water may enter the house—the more complex the roof, 

the more flashing you should see

Yes

Air gap between stucco, brick, or masonry cladding and housewrap Yes

Overhangs for shade and to direct water away from walls Yes

Trees planted ten feet from house, no overhanging branches Yes

Plantings 18 to 36 inches away from the foundation Yes

No wood or siding in direct contact with ground Yes

AIR BARRIERS

Follow ENERGY STAR Thermal Bypass Checklist Yes

All penetrations through exterior walls sealed Yes

Careful sealing of sheetrock or exterior sheathing Yes

Canned lights rated as airtight and for insulated ceiling (ICAT) Yes

Electrical boxes on exterior walls caulked or gasketed Yes

Holes into attic sealed Yes

Attic hatch weather-stripped and insulated Yes

Air leakage determined with house depressurization test Yes

Wall-roof intersection carefully sealed to avoid ice dams Yes

Draft stops installed behind tubs, showers, stairs, and fireplaces Yes

Garage completely sealed from conditioned areas of house Yes

Careful sealing around bathtubs, landings, fireplaces, kneewalls, 

cantilevered floors, etc. Yes

Sill plates gasketed or sealed Yes

APPENDIX I / BUILDING AMERICA BEST PRACTICES SERIES

A1.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
MEASURE Building America

Recommendations

Builder

#1

Builder

#2

Builder

#3

FOUNDATION MEASURES

Radon control measures installed Yes

4 to 6 inch gravel base under slab and basement floors Yes

Polyethylene (plastic) vapor barrier between gravel and slab Yes

Conditioned crawlspace Yes

Exterior slab insulation Yes

Termite flashing added at sill plate Yes

PLUMBING

No pipes in exterior walls Yes

Pipe insulation Yes

VENTILATION

Whole-house mechanical ventilation installed Yes

Spot ventilation installed in kitchen and bathrooms Yes

Clothes dryers are vented to the outside Yes

Gas-fired furnaces or water heaters sealed combustion, 

direct vented, or power vented Yes

Carbon monoxide detector installed in homes with a combustion 

appliance or attached garage Yes

Attached garages are ventilated Yes

FRAMING

Use Optimum Value Engineering (also called Advanced Framing):

- 2x6 24 in. oc instead of 2x4 18 in. oc studs

- Align framing members from floor joists to wall studs to rafters

- Use single top plates and single headers where possible

- Use two-stud corners and drywall clips instead of 3-stud corners

Yes

OTHER

Low VOC interior coatings Yes

Low VOC adhesives Yes

Low emission cabinets Yes

CFL lighting Yes

OTHER FEATURES FOR COMPARISON

*SEER: Seasonal Energy Efficiency Ratio | *AFUE: Annual Fuel Utilization Efficiency | *HVAC: heating, ventilation, and air conditioning

A1.3

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Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 A1.3
Appendix II.

DOE Building Energy Code 

Resource Center Code Notes

A meeting with the building department before construction is well 

advised. Should your code official need information in support of 

the new techniques you may use in an energy-efficient home, this 

appendix contains websites and a sample document that may be 

helpful. A set of draft code notes are available on DOE’s Building 

Energy Codes Resource Center website. These draft documents 

are written for code officials and provide a description of energyefficiency techniques, citations to relevant codes, and guidance for 

plan reviews and field inspections. 

Here is a list of available code notes that can help re-assure your 

local code official that the proposed techniques are both safe and 

in compliance with the model codes. The code notes are available at 

www.energycodes.gov/support/code_notes.stm.

•	 Single Top Plate

•	 No Headers in Nonbearing Walls

•	 Header Hangers in Bearing Walls

•	 Open Spaces as Return-Air Options

•	 Details for Mechanically Vented Crawl Spaces

•	 Ventilation Requirements for Condensing Clothes Dryers

•	 Drywall Clips

•	 Rigid Board Insulation Installed as Draft Stop in Attic Kneewall

•	 Whole-House Mechanical Ventilation

•	 Residential Heating and Cooling Load Calculation Requirements

•	 Conditioned Attics.

We have included one of these Code Notes as a sample in this 

document, the Code Note for Rigid Board Insulation Installed as 

Draft Stop in Attic Kneewall. You will find it on the pages that follow.

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BUILDING AMERICA BEST PRACTICES SERIES / APPENDIX II

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 A2.1
Rigid Board Insulation Installed as Draft Stop in Attic Kneewall -

Code Notes (DRAFT)

Framing kneewall

Rigid board insulation (foam plastic) is an effective draft stop and also increases the R-value of the attic

kneewall if installed on the attic side of the kneewall, replacing the need for separate draft stop and insulation

products. The IRC requires foam plastic insulation to be protected against ignition by using fiberglass batt

insulation, gypsum board or other products that meet the flame and smoke density requirements. Foam

plastic products rated for flame and smoke density can be installed without such a protective covering.

Insulating attic kneewalls between a conditioned space with vaulted ceilings and the attic is important to

reduce energy loss through the wall, especially in the summer months. To be effective, the insulation installed

in the kneewalls must be supported so that it stays in contact with the gypsum board, and protected against

air moving through the insulation.

http://energycode.pnl.gov/cocoon/energy/ Page 1 of 3

APPENDIX II / BUILDING AMERICA BEST PRACTICES SERIES

A2.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Kneewall sheathing insulation to increase R-value to equal the outside wall.

Foam plastic insulation can be installed on the attic side of the attic kneewall (see Figure) to both act as a

draft stop between the conditioned house and the unconditioned attic and to increase the insulation R-value of

the attic kneewall. Installing such an insulating backing in the kneewall supports the fiberglass batt insulation

between framing members, replaces an air barrier, and adds insulating value to the attic kneewall.

Plan Review

1. Verify that plastic insulation called out on the construction detail meets the ASTM E 84 requirements for

flame spread and smoke development. Require manufacturer literature or an ICC Evaluation Service

report.

2. Verify that the insulation R-value of the foam plastic insulation called out on the building plans meets or

exceeds the R-value requirements called for on the energy code compliance documentation (only if credit

has been taken for the foam plastic insulation).

Field Inspection

1. Verify that the foam plastic insulation installed in the field is consistent with that called out on the building

plans.

2. Verify that the insulation R-value specified on the insulation meets or exceeds the R value called out on the

plans or documentation.

3. Verify that that sealant has been installed around the edges of the insulation and that any holes or

penetrations in the foam plastic insulation are sealed.

Code Citations

http://energycode.pnl.gov/cocoon/energy/ Page 2 of 3

The R-value of the kneewall sheathing insulation should equal the R-value of the exterior wall insulation.

A2.3

BUILDING AMERICA BEST PRACTICES SERIES / APPENDIX II

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 A2.3
Appendix III.

Energy & Housing Glossary

Accreditation

The process of certifying a Home Energy 

Rating System (HERS) as being compliant 

with the national industry standard operating 

procedures for Home Energy Rating System.

AFUE Annual Fuel Utilization 

Efficiency (AFUE)

Measures the amount of fuel converted to 

space heat in proportion to the amount of 

fuel entering the furnace. This is commonly 

expressed as a percentage. A furnace with an 

AFUE of 90 could be said to be 90% efficient. 

AFUE includes any input energy required 

by the pilot light but does not include any 

electrical energy for fans or pumps. 

Air Barrier

Any material that restricts air flow. In wall 

assemblies, the exterior air barrier is often a 

combination of sheathing and either building 

paper, housewrap or board insulation. The 

interior air barrier is typically gypsum board. 

Air Flow Retarder

Air flow retarders are used to form a home’s 

pressure boundary. They retard air flow 

through the home’s walls, floors, and ceiling. 

Common air flow retarder materials include 

drywall that is taped and mudded at seams; 

OSB or plywood subflooring that is caulked at 

seams; plastic sheets placed between drywall 

and framing (should not to be used in hot and 

humid climates); exterior rigid foam insulating 

sheathing that is taped at seams; and building 

paper that is taped at seams. 

Building Envelope

The outer shell, or the elements of a building, 

such as walls, floors, and ceilings, that enclose 

conditioned space. See also Pressure Boundary 

and Thermal Boundary.

Btu (British Thermal Unit)

A standard unit for measuring energy. One Btu 

is the amount of energy required to raise the 

temperature of one pound of water by one 

degree Fahrenheit from 59 to 60. An InchesPounds unit.

CABO (Council of American 

Building Officials)

The previous umbrella organization for the 

three nationally recognized model code 

organizations in the United States: the Building 

Officials & Code Administrators International, 

Inc. (BOCA), the International Conference of 

Building Officials (ICBO), and the Southern 

Building Code Congress International (SBCCI). 

All were incorporated into the International 

Code Council in ICC in November of 1997 

with the goal of developing a single national 

building code in the United States. 

Capacity

The rate at which a piece of equipment works. 

Cooling capacity is the amount of heat a 

cooling system can remove from the air. For air 

conditioners total capacity is the sum of latent 

capacity, the ability to remove moisture from 

the air, and the sensible capacity, the ability to 

reduce dry-bulb temperature. Heating system 

capacity indicates how much heat a system 

can provide. Heating and cooling capacities are 

rated in Btu per hour.

Chase

An enclosure designed to hold ducts, 

plumbing, electric, telephone, cable, or other 

linear components. A chase designed for ducts 

should be in conditioned space and include air 

flow retarders and thermal barriers between it 

and unconditioned spaces such as attics.

Construction Documents

The drawings (plans) and written specifications 

that describe construction requirements for 

a building.

COP (Coefficient of 

Performance)

A measure of efficiency typically applied 

to heat pumps. The COP for heat pumps 

is the ratio, at a given point in time, of net 

heat output to total energy input expressed 

in consistent units and under designated 

conditions. Heat pumps result in a COP 

greater than 1 because the system delivers or 

removes more heat energy than it consumes. 

Other specific definitions of COP exist for 

refrigeration equipment. See HSPF for a 

description of a unit for seasonal efficiency.

Debt-to-Income Ratio

The ratio, expressed as a percentage, which 

results when a borrower’s total monthly 

payment obligations on long-term debt are 

divided by their gross monthly income. This is 

one of two ratios (housing expense-to-income 

ratio being the other) used by the mortgage 

industry to determine if a prospective borrower 

qualifies (meets the underwriting guidelines) for 

a specific home mortgage. Fannie Mae, Freddie 

Mac and FHA underwriting guidelines set an 

upper limit of 36% on this value for conventional 

loans but increase (“stretch”) the ratio by 2% for 

qualifying energy-efficient houses.

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Dry-Bulb Temperature

The temperature of air indicated on an ordinary 

thermometer, it does not account for the 

affects of humidity.

ECM 

(Energy Conservation Measure)

An individual building component or product 

that directly impacts energy use in a building.

EEM 

(Energy-Efficient Mortgage)

Specifically, a home mortgage for which the 

borrower’s qualifying debt-to-income and 

housing expense-to income ratios have been 

increased (“stretched”) by 2% because the 

home meets or exceeds CABO’s 1992 version of 

the Model Energy Code (MEC). This so-called 

“stretch” mortgage is nationally underwritten 

by Fannie Mae, Freddie Mac and the Federal 

Housing Administration (FHA). This term 

is often used generically to refer to any 

home mortgage for which the underwriting 

guidelines have been relaxed specifically for 

energy efficiency features, or for which any 

form of financing incentive is given for 

energy efficiency.

EER (Energy Efficiency Ratio)

A measurement of the instantaneous energy 

efficiency of cooling equipment, normally used 

only for electric air conditioning. EER is the 

ratio of net cooling capacity in Btu per hour to 

the total rate of electric input in watts, under 

designated conditions. The resulting EER value 

has units of Btu per watt-hour.

EF (Energy Factor)

A standardized measurement of the annual 

energy efficiency of water heating systems. 

It is the annual hot water energy delivered 

to a standard hot water load divided by the 

total annual purchased hot water energy 

input in consistent units. The resultant EF 

value is a percentage. EF is determined by a 

standardized U.S. Department of Energy (DOE) 

procedure.

Energy (Use)

The quantity of onsite electricity, gas or 

other fuel required by the building equipment 

to satisfy the building heating, cooling, hot 

water, or other loads or any other service 

requirements (lighting, refrigeration, 

cooking, etc.)

Energy Audit

A site inventory and descriptive record 

of features impacting the energy use in a 

building. This includes, but is not limited to all 

building component descriptions (locations, 

areas, orientations, construction attributes 

and energy transfer characteristics); all energy 

using equipment and appliance descriptions 

(use, make, model, capacity, efficiency and fuel 

type) and all energy features.

ENERGY STAR® Home

A home, certified by the U.S. Environmental 

Protection Agency (EPA), that is at least 30% 

more energy efficient than the minimum 

national standard for home energy efficiency 

as specified by the 1992 MEC, or as defined for 

specific states or regions. ENERGY STAR is a 

registered trademark of the EPA.

Envelope

See Building Envelope

Fannie Mae (FNMA - Federal 

National Mortgage Association)

A private, tax-paying corporation chartered by 

the U.S. Congress to provide financial products 

and services that increase the availability of 

housing for low-, moderate-, and middleincome Americans.

FHA (Federal Housing 

Administration)

A division of the U.S. Department of Housing 

and Urban Development (HUD). FHA’s main 

activity is the insurance of residential mortgage 

loans made by private lenders.

Freddie Mac 

(FHLMC - Federal Home Loan 

Mortgage Corporation)

A stockholder-owned organization, chartered 

by the U.S. Congress to increase the supply 

of mortgage funds. Freddie Mac purchases 

conventional mortgages from insured 

depository institutions and HUD-approved 

mortgage bankers.

Grade Beam

A foundation wall that is poured at or just 

below the grade of the earth, most often 

associated with the deepened perimeter 

concrete section in slab-on-grade foundations.

HERS 

(Home Energy Rating System)

A standardized system for rating the energyefficiency of residential buildings.

HERS Energy-Efficient 

Reference Home (EERH)

The EERH is a geometric “twin” to a home 

being evaluated for a HERS rating and 

according to a newly revised system, is 

configured to be minimally compliant with the 

2004 International Energy Conservation Code.

HERS Provider

An individual or organization responsible for 

the operation and management of a Home 

Energy Rating System (HERS).

HERS Rater

An individual certified to perform residential 

building energy efficiency ratings in the class 

for which the rater is certified.

HERS Index

The HERS Index is a scoring system established 

by the Residential Energy Services Network 

(RESNET) in which a home built to the 

specifications of the HERS Reference Home 

(based on the 2006 International Energy 

Conservation Code) scores a HERS Index of 

100, while a net zero energy home scores a 

HERS Index of 0. The lower a home’s HERS 

Index, the more energy efficient it is in 

comparison to the HERS Reference Home.

Each 1-point decrease in the HERS Index 

corresponds to a 1% reduction in energy 

consumption compared to the HERS Reference 

Home. Thus a home with a HERS Index of 85 

is 15% more energy efficient than the HERS 

Reference Home and a home with a HERS 

Index of 70 is 30% more energy efficient.

Housing Expense-to-Income Ratio

The ratio, expressed as a percentage, which 

results when a borrower’s total monthly 

housing expenses (P.I.T.I.) are divided by their 

gross monthly income. This is one of two 

ratios (debt-to-income ratio being the other) 

used by the mortgage industry to determine 

if a prospective borrower qualifies (meets the 

underwriting guidelines) for a specific home 

mortgage. Fannie Mae, Freddie Mac and FHA 

underwriting guidelines set an upper limit 

of 28% on this value for conventional loans 

but increase (“stretch”) the ratio by 2% for 

qualifying Energy-Efficient Mortgages (EEM).

APPENDIX III / BUILDING AMERICA BEST PRACTICES SERIES

A3.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
Housewrap

Any of several spun-fiber polyolefin rolled 

sheet goods for wrapping the exterior of the 

building envelope.

HSPF (Heating Season 

Performance Factor)

A measurement of the seasonal efficiency 

of an electric heat pump using a standard 

heating load and outdoor climate profile over 

a standard heating season. It represents the 

total seasonal heating output in Btu divided by 

the total seasonal electric power input in watthours (Wh). Thus, the resultant value for HSPF 

has units of Btu/Wh.

Infrared Imaging

Heat sensing camera which helps reveal 

thermal bypass conditions by exposing hot 

and cold surface temperatures revealing 

unintended thermal flow, air flow, and moisture 

flow. Darker colors indicate cool temperatures, 

while lighter colors indicate warmer 

temperatures.

Insulated Concrete Forms (ICFs)

Factory-built wall system blocks that are made 

from extruded polystyrene insulation. Steel 

reinforcing rods are added and concrete is 

poured into the voids, creating a very air-tight, 

well insulated and sturdy wall as the insulation 

is inherently aligned with the exterior and 

interior air barriers.

Insulation Contact, Air-Tight 

(ICAT) Lighting Fixture

Rating for recessed lights that can have direct 

contact with insulation and constructed with 

air-tight assemblies to reduce thermal losses.

Jump Duct

A flexible, short, U-shaped duct (typically 

10-inch diameter) that connects a room to 

a common space as a pressure balancing 

mechanism. Jump ducts serve the same 

function as transfer grilles.

Load

The quantity of heat that must be added to 

or removed from the building (or the hot 

water tank) to satisfy specific levels of service, 

such as maintaining space temperature or hot 

water temperature at a specified thermostat 

setting (see also the definitions of energy 

and thermostat).

Low-E

Refers to a coating for high-performance 

windows, the “E” stands for emissivity or 

re-radiated heat flow. The thin metallic oxide 

coating increases the U-value of the window 

by reducing heat flow from a warm(er) air 

space to a cold(er) glazing surface. Low-E 

coatings allow short-wavelength solar radiation 

through windows, but reflect back longer 

wavelengths of heat.

MEC (Model Energy Code)

A “model” national standard for residential 

energy efficiency. The MEC was developed 

through a national consensus process by 

the Council of American Building Officials 

(CABO) and is the accepted national minimum 

efficiency standard for residential construction. 

Since MEC is a model code, it does not have 

the “force of law” until it is adopted by a local 

code authority. The MEC is used as the national 

standard for determining Energy-Efficient 

Mortgage (EEM) qualification, and it serves 

as the national “reference point” used by 

Home Energy Rating Systems (HERS) in the 

determination of energy ratings for homes.

Mechanical Ventilation

The active process of supplying or removing 

air to or from an indoor space by powered 

equipment such as motor-driven fans and 

blowers, but not by devices such as winddriven turbine ventilators and mechanically 

operated windows.

Optimal Value Engineering 

(OVE)

A strategy for reducing thermal bridging by 

minimizing wall framing needed for structural 

support. Common techniques include 2x6 

framing with 24" on-center spacing, single top 

plates where trusses align with wall framing 

below, properly sized headers, two-stud 

corners, lattice strips at exterior/interior wall 

intersections, and the elimination of excessive 

fire blocking and window framing. This results 

in much more open framing for insulation to 

improve energy efficiency and comfort.

Performance Test

An on-site measurement of the energy 

performance of a building energy feature or an 

energy using device conducted in accordance 

with pre-defined testing and measurement 

protocols and analysis and computation 

methods. Such protocols and methods may 

be defined by national consensus standards 

like those of the American Society of Heating, 

Refrigerating and Air Conditioning Engineers 

(ASHRAE) and the American Society for Test 

and Measurement (ASTM).

P.I.T.I.

An abbreviation which stands for principal, 

interest, taxes, and insurance. These generally 

represent a borrower’s total monthly payment 

obligations on a home loan. The taxes and 

insurance portion are often paid monthly to 

an impound or escrow account and may be 

adjusted annually to reflect changes in the 

cost of each.

Pressure Boundary

The point in a building at which inside air and 

outside air are separated. If a building were 

a balloon, the rubber skin would form the 

pressure boundary. Where inside and outside 

air freely mingle there is no pressure boundary.

Pressurization Test

A procedure in which a fan is used to place a 

house, duct system, or other container, under 

positive or negative air pressure in order to 

calculate air leakage.

RESNET (Residential Energy 

Services Network)

The national association of energy rating 

providers.

Rated Home

A specific residence that is evaluated by an 

energy rating.

R-Value

Measures a material’s ability to slow down or 

resist the transfer of heat energy, also called 

thermal resistance. The greater the R-value, the 

better the resistance, the better the insulation. 

The effective R-value of an insulation material 

will be reduced by gaps, voids, compression or 

misalignment. R-values are the reciprocal of 

U-values. See U-values for more information.

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BUILDING AMERICA BEST PRACTICES SERIES / APPENDIX III

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Sealed Combustion

Sealed combustion means that a combustion 

appliance, such as a furnace, water heater, 

or fireplace, acquires all air for combustion 

though a dedicated sealed passage from 

the outside; combustion occurs in a sealed 

combustion chamber, and all combustion 

products are vented to the outside through a 

separate dedicated sealed vent.

SEER (Seasonal Energy 

Efficiency Ratio)

A measurement similar to HSPF except that 

it measures the seasonal cooling efficiency of 

an electric air conditioner or heat pump using 

a standard cooling load and outdoor climate 

profile over a standard cooling season. It 

represents the total seasonal cooling output in 

Btu divided by the total seasonal electric input 

in watt hours (Wh). The SEER value are units 

of Btu/Wh.

Semi-Permeable

The term vapor semi-permeable describes 

a material with a water vapor permeance 

between 1 and 10 Perms. Water vapor can pass 

through a semi-permeable material but at a 

slow rate.

Shading Coefficient (SC)

The ratio of the total solar heat admittance 

through a given glazing product relative to 

the solar heat admittance of double-strength, 

clear glass at normal solar incidence (i.e., 

perpendicular to the glazing surface).

Site Energy

The energy consumed at a building location or 

other end–use site.

Solar Heat Gain Coefficient 

(SHGC)

SHGC measures how well a window blocks heat 

caused by sunlight. The lower the SHGC rating 

the less solar heat the window transmits. This 

rating is expressed as a fraction between 0 and 

1. The number is the ratio of a window’s solar 

heat admittance compared to the total solar 

heat available on the exterior window surface 

at normal solar incidence (i.e., perpendicular to 

the glazing surface).

Sone

A sound rating. Fans rated 1.5 sones and below 

are considered very quiet.

Source Energy

All the energy used to deliver energy to a site, 

including power generation and transmission 

and distribution losses (also called primary 

energy). Approximately three watts (or 10.239 

British thermal units) of energy is consumed to 

deliver one watt of usable electricity. Building 

America energy saving targets are measured in 

terms of source energy rather than site energy.

Structural Insulated Panels 

(SIPs)

Factory-built insulated wall assemblies that 

ensure full alignment of insulation with 

integrated air barriers. Composed of insulated 

foam board glued to both an internal and 

external layer of sheathing (typically OSB or 

plywood). Many SIP panels are manufactured 

with precut window and door openings.

Supply ducts

The ducts in a forced air heating or cooling 

system that supply heated or cooled air 

from the furnace or air conditioner to 

conditioned spaces.

Thermal Boundary

The border between conditioned and 

unconditioned space where insulation should 

be placed.

Thermal Bridging

Accelerated thermal flow that occurs 

when materials that are poor insulators 

displace insulation.

Thermostat

A control device that measures the 

temperature of the air in a home or the water 

in a hot water tank and activates heating or 

cooling equipment to cause the air or water 

temperature to remain at a pre-specified value, 

normally called the set point temperature.

Ton(s) of Refrigeration

Units used to characterize the cooling capacity 

of air conditioning equipment. One ton equals 

12,000 Btu/h.

U-Value

Measures the rate at which heat flows or 

conducts through a building assembly (wall, 

floor, ceiling, etc.). The smaller the U-value the 

more energy efficient an assembly and the 

slower the heat transfer. Window performance 

labels include U-values (calling them U factors) 

to help in comparing across window products.

Ventilation

The controlled movement of air into and out 

of a house.

W (watt)

One of two (Btu/h is the other) standard units 

of measure for the rate at which energy is 

consumed by equipment or the rate at which 

energy moves from one location to another. 

It is also the standard unit of measure for 

electrical power.

Wet-Bulb Temperature

A measure of combined heat and humidity. 

At the same temperature, air with less relative 

humidity has a lower wet-bulb temperature. 

See Dry-Bulb Temperature.

Wind Baffle

An object that serves as an air barrier for 

the purpose of blocking wind washing at 

attic eaves.

Wind-Washing

Air movement due to increased pressure 

differences that occur at the outside corners 

and roof eaves of buildings. Wind-washing 

can have significant impact on thermal and 

moisture movement and hence thermal 

and moisture performance of exterior wall 

assemblies.

Xeriscaping

Landscaping that minimizes outdoor water use 

while maintaining soil integrity and building 

aesthetics. Typically includes emphasis on 

native plantings, mulching, and no or limited 

drip/subsurface irrigation.

Zero Energy House

Any house that over time, averages out to netzero energy consumption. A zero energy home 

may supply more energy than it needs during 

peak demand, typically using one or more solar 

energy strategies, energy storage and/or 

net metering.

APPENDIX III / BUILDING AMERICA BEST PRACTICES SERIES

A3.4 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
ACCA Air Conditioning Contractors of America

ACH air changes per hour 

ACI Affordable Comfort Incorporated

ACT2 Advanced Customer Technology Test 

for Maximum Energy Efficiency 

AFUE Annual Fuel Utilization Efficiency 

AHU air-handler unit 

AL air leakage

ALA American Lung Association 

APA The Engineered Wood Association

ASCE American Society of Civil Engineers

ASHRAE American Society of Heating, Refrigerating, 

and Air Conditioning Engineers

ASTM American Society for Testing and Materials

BECT Building Energy Code Training 

BEopt Software developed by NREL for identifying 

optimal building design 

BESTEST A benchmark for building energy simulation: 

Building Energy Simulation Test and 

Diagnostic Method 

BII Building Industry Institute 

BIRA Building Industry Research Alliance

BPI Building Performance Institute 

BSC Building Science Corporation

BSC Building Science Consortium

BTU British Thermal Unit

CAD computer-aided design 

CARB Consortium for Advanced Residential Buildings

CDCU Community Development Corporation of Utah 

CDD cooling degree days

CEC California Energy Commission 

CFL compact fluorescent light 

CFM cubic feet per minute 

CGSB Canadian General Standards Board

COP coefficient of performance

CR condensation resistance

CRI color-rendering index 

CT color temperature 

DHW domestic hot water 

DOE U.S. Department of Energy 

DOE2 Building energy analysis program that can predict 

the energy use and cost for all types of buildings 

ECM electronically commutated motor 

(or energy conservation measure)

EDHA Eastern Dakota Housing Alliance 

EEBA Energy and Environmental Building Alliance 

EEM Energy-efficient mortgages 

EER Energy Efficiency Rating 

EERH Energy-Efficient Reference Home

Appendix IV.

Acronyms and Abbreviations

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BUILDING AMERICA BEST PRACTICES SERIES / APPENDIX IV

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 A4.1
EF energy factor 

EFL Environments for Living® 

EGUSA Energy-Gauge USA software (FSEC’s residential 

front-end user interface for DOE2.1E simulation tool) 

EPDM Ethylene Propylene Diene Monomer

EPA U.S. Environmental Protection Agency 

EPS expanded polystyrene 

ERV energy recovery ventilator

EVHA Energy Value Housing Award

FEMA Federal Emergency Management Agency

FF framing factor 

FFA finished floor area 

FG fiberglass 

FHA Federal Housing Administration

FSEC Florida Solar Energy Center

GAMA Gas Appliance Manufacturers Association

GenOpt generic optimization program 

HVAC heating, ventilating, and air conditioning 

HDD heating degree days

HERS Home Energy Rating System developed 

by RESNET 

HPL high-performance lighting 

HRV heat recovery ventilator 

HSPF Heating Seasonal Performance Factor 

HUD U.S. Department of Housing and Urban 

Development 

IAQ Indoor air quality 

IBACOS Integrated Building and Construction Solutions

IBHS Institute for Business and Home Safety

IC insulated ceiling

ICAT Insulation-Contact Air-Tight 

ICC International Code Council

IDEC Indirect-Direct Evaporative Cooler 

IDP Integrated Design Process 

IECC International Energy Conservation Code 

IEQ Indoor Environmental Quality 

IHP Industrialized Housing Partnership

IOSEU incremental overall source energy use 

IRC International Residential Code

Mcf million cubic feet 

MEC Model Energy Code (supplanted by IECC in 1998)

MEF modified energy factor 

MERV Minimum Efficiency Reporting Value 

NAECA National Appliance Energy Conservation Act 

NAHB National Association of Home Builders 

NAHB RC National Association of Home Builders 

Research Center

NASEO National Association of State Energy Officials 

NATE North American Technician Excellence 

NFRC National Fenestration Rating Council

NHQ National Housing Quality 

NREL National Renewable Energy Laboratory

NZEH net-zero energy home 

OA outdoor air

OASys a high-efficiency indirect/direct evaporative cooler 

developed by Davis Energy Group 

oc on center 

ODOE Oregon Department of Energy

ORNL Oak Ridge National Laboratory

OSB oriented strand board 

Pa Pascal, unit of pressure measurement 

PATH Partnership for Advancing Technology in Housing 

PEX cross-linked Polyethylene tubing 

PITI principal, interest, tax, and insurance 

PNNL Pacific Northwest National Laboratory

PSC permanent split-capacitor motors 

PV photovoltaics 

APPENDIX IV / BUILDING AMERICA BEST PRACTICES SERIES

A4.2 Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011
R-Value A measure of thermal resistance used to describe 

thermal insulation materials in buildings 

R.A.P. return-air pathway 

RESNET Residential Energy Service Network 

RH relative humidity 

SA supply air 

SBIC Sustainable Buildings Industry Council

SC shading coefficient

SEER seasonal energy efficiency ratio 

SHGC solar heat gain coefficient 

SHW solar hot water 

SLA specific leakage area 

SIP structural insulated panels

TAB testing, adjusting, and balancing

TIP Termite Infestation Probability 

TMY2 Typical Meteorological Year weather data 

TOU time of use 

TXV thermostatic expansion valve

UL Underwriter’s Laboratory 

USDA US Department of Agriculture

USGBC US Green Building Council

U-Value The thermal transmittance of a material, 

incorporating the thermal conductance of 

the structure along with heat transfer resulting 

from convection and radiation. 

UA heat loss coefficient 

UL Underwriter’s Laboratories

UV ultraviolet

VA Veterans Administration

VOC volatile organic compounds 

VT visible transmittance

WAC Washington Administrative Code

WSBCC Washington State Building Code Council

WSU Washington State University

WUFI Modeling program for simulating heat 

and moisture transfer 

XPS extruded polystyrene 

ZEH zero energy home 

ZNE zero net energy

A4.3

BUILDING AMERICA BEST PRACTICES SERIES / APPENDIX IV

Volume 12. 40% Whole-House Energy Savings in the Cold and Very Cold Climates - February 2011 A4.3
EERE Information Center 

1-877-EERE-INF (1-877-337-3463) 

www.eere.energy.gov/informationcenter

PNNL-20139 February 2011

For information on Building America 

visit www.buildingamerica.gov. 

The website contains expanded 

case studies, technical reports, and 

best practices guides.

Building America Program

George S. James • New Construction • 202-586-9472 • fax: 202-586-8134 • e-mail: George.James@ee.doe.gov

Building America Program • Office of Building Technologies, EE-2J • U.S. Department of Energy •

1000 Independence Avenue, S.W. • Washington, D.C. 20585-0121 • www.buildingamerica.gov

Building Industry Research Alliance (BIRA)

Robert Hammon • ConSol • 7407 Tam O’Shanter Drive #200 • Stockton, CA 95210-3370 • 209-473-5000 •

fax: 209-474-0817 • e-mail: Rob@consol.ws • www.bira.ws

Building Science Consortium (BSC)

Betsy Pettit • Building Science Consortium (BSC) • 70 Main Street • Westford, MA 01886 • 978-589-5100 •

fax: 978-589-5103 • e-mail: Betsy@buildingscience.com • www.buildingscience.com

Consortium for Advanced Residential Buildings (CARB)

Steven Winter • Steven Winter Associates, Inc. • 50 Washington Street • Norwalk, CT 06854 •

203-857-0200 • fax: 203-852-0741 • e-mail: swinter@swinter.com • www.carb-swa.com

Davis Energy Group

David Springer • Davis Energy Group • 123 C Street • Davis, CA 95616 • 530-753-1100 • fax: 530-753-4125 •

e-mail: springer@davisenergy.com • deg@davisenergy.com • www.davisenergy.com/index.html

IBACOS Consortium

Brad Oberg • IBACOS Consortium • 2214 Liberty Avenue • Pittsburgh, PA 15222 • 412-765-3664 •

fax: 412-765-3738 • e-mail: boberg@ibacos.com • www.ibacos.com

Industrialized Housing Partnership (IHP)

Philip Fairey • Florida Solar Energy Center • 1679 Clearlake Road • Cocoa, FL 32922 • 321-638-1005 •

fax: 321-638-1439 • e-mail: pfairey@fsec.ucf.edu • www.baihp.org

National Association of Home Builders (NAHB) Research Center

Tom Kenney • National Association of Home Builders (NAHB) Research Center •

400 Prince George’s Boulevard • Upper Marlboro, MD 20774 • 301-430-6246 •

fax: 301-430-6180 • toll-free: 800-638-8556 • www.nahbrc.org

National Renewable Energy Laboratory

Ren Anderson • 1617 Cole Boulevard, MS-2722 • Golden, CO 80401 • 303-384-7433 • fax: 303-384-7540 •

e-mail: ren_anderson@nrel.gov • www.nrel.gov

Tim Merrigan • 1617 Cole Boulevard, MS-2722 • Golden, CO 80401 • 303-384-7349 • fax: 303-384-7540 •

e-mail: tim_merrigan@nrel.gov • www.nrel.gov

Oak Ridge National Laboratory

Pat M. Love • P.O. Box 2008 • One Bethel Valley Road • Oak Ridge, TN 37831 • 865-574-4346 •

fax: 865-574-9331 • e-mail: lovepm@ornl.gov • www.ornl.gov

Pacific Northwest National Laboratory

Michael Baechler • 620 SW 5th, Suite 810 • Portland, OR 97204 • 503-417-7553 • fax: 503-417-2175 •

e-mail: michael.baechler@pnl.gov • www.pnl.gov

Produced for the U.S. Department of Energy (DOE) by Pacific Northwest National Laboratory, 

Contract DE-AC05-76RLO 1830.

Printed with a renewable-source ink on paper containing at least 50% wastepaper, including 20% postconsumer waste.

Research and 

Development of Buildings

Our nation’s buildings consume 

more energy than any other sector 

of the U.S. economy, including 

transportation and industry. 

Fortunately, the opportunities to 

reduce building energy use—and 

the associated environmental 

impacts—are significant.

DOE’s Building Technologies 

Program works to improve the 

energy efficiency of our nation’s 

buildings through innovative new 

technologies and better building 

practices. The program focuses 

on two key areas:

•	 Emerging Technologies

Research and development of 

the next generation of energyefficient components, materials, 

and equipment

•	 Technology Integration of new

technologies with innovative 

building methods to optimize 

building performance and savings

Visit our Web sites at:

www.buildingamerica.gov

www.pathnet.org

www.energystar.gov

R