Retrofit of a Multifamily 

Mass Masonry Building 

in New England

K. Ueno, P. Kerrigan, Jr., H. Wytrykowska, 

and R. Van Straaten

Building Science Corporation

August 2013
NOTICE

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iii

Retrofit of a Multifamily Mass Masonry Building in New England

Prepared for: 

The National Renewable Energy Laboratory 

On behalf of the U.S. Department of Energy’s Building America Program 

Office of Energy Efficiency and Renewable Energy 

15013 Denver West Parkway 

Golden, CO 80401 

NREL Contract No. DE-AC36-08GO28308 

Prepared by: 

K. Ueno, P. Kerrigan, Jr., H. Wytrykowska, and R. Van Straaten 

Building Science Corporation 

30 Forest Street

Somerville, MA 02143

NREL Technical Monitor: Cheryn Metzger

Prepared under Subcontract No. KNDJ-0-40337-03 

August 2013 
iv

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v 

Contents

List of Figures ........................................................................................................................................... vii

List of Tables ............................................................................................................................................ viii

Definitions ................................................................................................................................................... ix

Executive Summary.................................................................................................................................... x

1 Introduction ........................................................................................................................................... 1

1.1 Background ..........................................................................................................................2

2 Brick Material Property Testing and Hygrothermal Simulations..................................................... 5

2.1 Material Property Testing ....................................................................................................5

2.1.1 Dry Density ..............................................................................................................5

2.1.2 Water Absorption or Uptake Coefficient (A-Value) ...............................................5

2.1.3 Free Water Saturation ..............................................................................................6

2.1.4 Vacuum Saturation ...................................................................................................6

2.1.5 Critical Degree of Saturation ...................................................................................6

2.2 Hygrothermal Simulations ...................................................................................................7

2.2.1 Air Leakage ..............................................................................................................8

2.2.2 Climate Data ............................................................................................................8

2.3 Material Properties .............................................................................................................10

2.3.1 Assessing Freeze-Thaw Degradation Risk ............................................................10

2.3.2 Enclosure Assemblies Modeled .............................................................................10

2.4 Hygrothermal Simulation Results ......................................................................................12

2.5 Conclusions ........................................................................................................................14

3 Predicted Energy Performance and Cost Impacts of Proposed Wall Retrofit Design ................ 19

3.1 Wall Retrofit Options .........................................................................................................19

3.2 BEopt Parametric Analysis ................................................................................................20

3.3 Results

3.3.1 Wall Retrofit Energy Performance ........................................................................21

3.3.2 Wall Retrofit Cost Analysis ...................................................................................22

3.3.3 BEopt Most Cost-Effective Wall Option ...............................................................22

4 Impact of Rebates and Incentives on Decision-Making Process .................................................. 24

4.1 National Grid Deep Energy Retrofit Pilot Program ...........................................................24

4.2 ENERGY STAR-Qualified Homes ...................................................................................24

4.2.1 Program Information ..............................................................................................24

4.2.2 Building Energy Analysis ......................................................................................25

4.3 Window Performance Analysis .........................................................................................26

4.4 Other Incentives .................................................................................................................30

5 Retrofit Air Barrier Strategies and Assemblies............................................................................... 31

5.1 Exterior Wall Air Barrier ...................................................................................................31

5.2 Roof and Roof-to-Wall Air Barrier ....................................................................................35

5.3 Below-Grade Air Barrier ...................................................................................................39

5.4 Compartmentalization Details ...........................................................................................43

6 Retrofit Mechanical Design ............................................................................................................... 52

6.1 Hydronic Heating ...............................................................................................................53

6.1.1 Positive ...................................................................................................................54

6.1.2 Negative .................................................................................................................55

6.1.3 Additional Design Considerations .........................................................................57

6.1.4 Updated Hydronic Schematic ................................................................................58
vi 

6.1.5 Cost Comparison ....................................................................................................59

6.1.6 Peak Load Analysis................................................................................................59

6.2 Dilution Ventilation ...........................................................................................................59

6.2.1 Original Design ......................................................................................................60

6.2.2 Current Ventilation Design—Building Science Corporation ................................61

6.2.3 Cost Comparison ....................................................................................................65

6.3 Kitchen Exhaust and Clothes Dryer ...................................................................................65

7 Actual Energy Performance Versus Predicted Site Energy Use ................................................... 67

7.1 Predicted Site Energy Use .................................................................................................67

7.2 Actual Energy Performance ...............................................................................................69

8 Construction Cost for Retrofit Measures......................................................................................... 70

8.1.1 Roof........................................................................................................................70

8.1.2 Walls ......................................................................................................................70

8.1.3 Basement Walls .....................................................................................................70

8.1.4 Basement Slab ........................................................................................................70

8.1.5 Heating and Domestic Hot Water ..........................................................................71

8.1.6 Ventilation..............................................................................................................71

8.1.7 Lighting ..................................................................................................................71

8.1.8 Appliances..............................................................................................................71

9 Conclusion .......................................................................................................................................... 72

9.1 Overview ............................................................................................................................72

9.2 Brick Material Property Testing and Hygrothermal Simulations ......................................72

9.3 Predicted Energy Performance and Cost Impacts of Proposed Wall Retrofit Design .......72

9.4 Impact of Rebates and Incentives on Decision Making Process .......................................73

9.5 Retrofit Air Barrier Strategies and Assemblies .................................................................73

9.6 Retrofit Mechanical Design ...............................................................................................74

9.7 Actual Energy Performance Versus Predicted Site Energy Use ........................................74

References................................................................................................................................................. 75

Appendix A: MVHfH Site Assessment .................................................................................................... 78

Appendix B: MVHfH Retrofit Construction Details.............................................................................. 101

Appendix C: MVHfH REM/Rate Energy Modeling Results.................................................................. 134

Appendix D: MVHfH Mechanical Design............................................................................................... 139
vii 

List of Figures

Figure 1. MVHfH retrofit building in Lawrence, Massachusetts............................................................. 2

Figure 2. MVHfH retrofit building aerial views ......................................................................................... 3

Figure 3. MVHfH building section.............................................................................................................. 4

Figure 4. WUFI 5.1 Pro temperature and humidity for a “typical” cold year in Boston....................... 8

Figure 5. WUFI 5.1 pro climate summary for a “typical” cold year in Boston...................................... 9

Figure 6. Indoor conditions used in WUFI simulation (temperature and relative humidity) ............... 9

Figure 7. WUFI model of existing original building masonry wall assembly (solid brick wythes)... 11

Figure 8. WUFI model of existing addition masonry wall assembly (hollow clay tile backup)......... 11

Figure 9. WUFI model of addition masonry wall assembly with insulation retrofit ........................... 12

Figure 10. WUFI model of original building masonry wall assembly with insulation retrofit ........... 12

Figure 11. Example moisture content plot, correlated with assembly layers..................................... 13

Figure 12. Predicted moisture distribution during freezing temperatures: existing original building 

wall assembly, normal exposure, east facing, heating only.......................................................... 15

Figure 13. Predicted moisture distribution during freezing temperatures: existing addition wall 

assembly, normal exposure, east facing, heating only.................................................................. 16

Figure 14. Predicted moisture distribution during freezing temperatures: retrofit original building 

wall assembly, normal exposure, east facing, heating only.......................................................... 17

Figure 15. Predicted moisture distribution during freezing temperatures: retrofit addition wall 

assembly, normal exposure, east facing, heating only.................................................................. 18

Figure 16. Unit 8 floor layout.................................................................................................................... 20

Figure 17. Unit 8 BEopt parametric results—average source energy use.......................................... 21

Figure 18. Unit 8 BEopt parametric results—minimum cost................................................................ 22

Figure 19. BEopt most cost-effective wall option—2 in. ccSPF + 5.5 in. fiberglass batt................... 23

Figure 20. Existing vinyl double-glazed (clear) insert replacement windows .................................... 27

Figure 21. Test retrofit installation of flashing at the wood framed window openings ..................... 27

Figure 22. (L) Exterior wall conditions at solid brick; (R) hollow clay block infill conditions .......... 31

Figure 23. (L) Wall section at solid brick; (R) at hollow clay block infill conditions.......................... 32

Figure 24. (L) Test installation of foam on masonry; (R) use of polyurethane adhesive .................. 33

Figure 25. (L) Multiple layers of insulation; (R) mockup for volunteer education.............................. 33

Figure 26. (L) Framing installed inboard of insulation; (R) conditions at window opening.............. 34

Figure 27. Window jamb retrofit detail, showing spray foam “fillet” for air barrier continuity......... 35

Figure 28. (L) Lower roof, showing upper roof; (R) upper roof............................................................ 36

Figure 29. Lower roof retrofit detail at parapet ...................................................................................... 37

Figure 30. Insulation of lower roof, showing lack of air barrier at board sheathing.......................... 37

Figure 31. (L) Lower roof, showing upper roof; (R) upper roof............................................................ 38

Figure 32. Upper roof retrofit detail at intersection with sloping roof................................................. 38

Figure 33. (L) Upper roof typical conditions; (R) upper roof edge detail ............................................ 39

Figure 34. (L) Rigid wall insulation left clear of roof; (R) infill with spray foam kit............................ 39

Figure 35. “Perfect slab,” showing polyethylene and insulation control layers................................ 40

Figure 36. Typical basement slab and bottom of wall detail ................................................................ 41

Figure 37. (L) 4 in. nominal corrugated drainage pipe; (R) low-profile radon vent mat .................... 42

Figure 38. (L) Dimpled core of radon vent mat; (R) radon vent map installed under XPS................ 42

Figure 39. (L) Installed subslab insulation at basement; (R) detail of slab edge insulation............. 43

Figure 40. (L) Edge detail after casting of slab; (R) installation of interior framing........................... 43

Figure 41. (L) Three-dimensional multilayer multicell analogue; (R) air pressure fields connecting 

noncontiguous spaces) ..................................................................................................................... 44

Figure 42. Unit-to-unit floor/ceiling assembly at exterior wall; joists perpendicular to wall ............ 45

Figure 43. (L) Floor/ceiling fire separation gypsum board; (R) conditions after interior framing.... 45

Figure 44. (L) Rim joist foam blocks; (R) close-up showing clamping jig .......................................... 46

Figure 45. (L) Floor edge detail, showing added floor sheathing; (R) air seal between foam and 

floor ...................................................................................................................................................... 46

Figure 46. Rated partition intersection with exterior wall..................................................................... 47

Figure 47. Within-unit (nonrated) partition wall intersection with ceiling........................................... 48
viii

Figure 48. (L) Soffit with air barrier continuous above; (R) air sealing of top plate penetrations.... 49

Figure 49. Unit-to-unit (rated) floor-to-ceiling assembly at demising wall; joists parallel to wall.... 49

Figure 50. (L) Notched gypsum board at demising wall; (R) ceiling gypsum board continuous over 

unit interior partition walls ................................................................................................................ 50

Figure 51. Original apartment hydronic schematic ............................................................................... 54

Figure 52: Thermal efficiency plot as a function of inlet water temperature..................................... 55

Figure 53. Smith Environmental HE2 high-capacity hybrid element................................................... 56

Figure 54. Watts manifold with flow meters and balancing valves at each tap.................................. 57

Figure 55. Grundfos ALPHA variable-speed pump .............................................................................. 58

Figure 56. Updated apartment hydronic schematic .............................................................................. 58

Figure 57. Existing ventilation design at Unit 4 ..................................................................................... 61

Figure 58. Ventilation strategy schematic.............................................................................................. 62

Figure 59. Proposed HRV installation example ..................................................................................... 63

Figure 60. Example of current HRV duct layout .................................................................................... 64

Figure 61. Dual exterior hood .................................................................................................................. 64

Figure 62. Exhausto subduct riser and schematic................................................................................ 66

Figure 63. Unit 8 BEopt optimization results—cost versus energy use ............................................. 69

Figure 64. Unit 8 BEopt optimization results—average source energy use....................................... 69

Unless otherwise noted, all figures were created by BSC.

List of Tables

Table 1. Brick Material Property Testing Results .................................................................................... 7

Table 2. BEopt Energy Modeling Inputs for Wall Retrofit Options ...................................................... 21

Table 3. ENERGY STAR Tier Levels........................................................................................................ 25

Table 4. REM/Rate Energy Modeling Inputs........................................................................................... 26

Table 5. REM/Rate Modeling Results ...................................................................................................... 26

Table 6. Window Cost Comparison ......................................................................................................... 28

Table 7. Window Performance Energy Analysis.................................................................................... 29

Table 8. Air Leakage Through Masonry Materials ................................................................................. 32

Table 9. Air Barrier Connections Between Air Barrier Element Detail Listing ................................... 50

Table 10. Original Hydronic Design Cost (Whole Building).................................................................. 59

Table 11. BSC Current Hydronic Design Cost (Whole Building).......................................................... 59

Table 12. Original HRV Design Cost (Centralized System)................................................................... 65

Table 13. BSC Current HRV Design Cost (Individualized Systems).................................................... 65

Table 14. Selected Component Options for BEopt Modeling............................................................... 67

Table 15. BEopt “Design Case” Energy Modeling Inputs..................................................................... 68

Table 16. Construction Cost for Retrofit Measures............................................................................... 70

Unless otherwise noted, all tables were created by BSC.
ix

Definitions

ACH 50 Air changes per hour at 50 Pascal test pressure

ASHRAE American Society of Heating, Refrigerating and AirConditioning Engineers 

BEoptTM Building Energy Optimization Program

BSC Building Science Corporation

ccSPF Closed-cell spray polyurethane foam

CFL Compact fluorescent lamp

CFM Cubic feet per minute

DHW Domestic hot water

FT Freeze-thaw

HERS Home Energy Rating System

HRV Heat recovery ventilator

HVAC Heating, ventilation, and air conditioning

MVHfH Merrimack Valley Habitat for Humanity

RESNET Residential Energy Services Network

Scrit Critical degree of saturation

SEER Seasonal energy efficiency ratio

SHGC Solar heat gain coefficient

WUFI Wärme- und Feuchte Instationär

XPS Extruded polystyrene
x 

Executive Summary

Merrimack Valley Habitat for Humanity (MVHfH) has partnered with Building Science 

Corporation (BSC) to provide high performance affordable housing for 10 families in the retrofit 

of an existing brick building (a former convent) into condominiums. 

The condominium conversion project will contribute to several areas of space conditioning, 

water heating, and enclosures research. Enclosure items include insulation of mass masonry 

building on the interior, airtightness of these types of retrofits, multiunit building 

compartmentalization, window selection and roof insulation strategies. Mechanical system items 

include combined hydronic and space heating systems with hydronic distribution in small (lowload) units, and ventilation system retrofits for multifamily buildings.

One of the initial questions in this renovation project was whether the existing mass masonry 

walls could be retrofitted with insulation without durability problems. To understand these risks, 

the team performed a site assessment followed by material property testing and hygrothermal 

simulations. The section covering the analysis includes a summary of the material property 

testing results, a description of the hygrothermal computer simulations, and an interpretation of 

the results. Key findings included the following: 

• In both wall assemblies simulated, at normal rain exposures, brick freeze-thaw risk is 

predicted to be minimal with or without the thermal insulation retrofit. 

• The existing brickwork damage is likely due to the combination of rainwater 

concentrations due to poor maintenance and details (e.g., gutter/downspout failures). 

• The rainwater management issues associated with the existing areas of damage must be 

addressed as the thermal insulation retrofit will exacerbate such problems. 

Applying the results of the masonry retrofit analysis to a wider array of projects is beyond the 

scope of this report; an overview of the topic is covered by Straube et al. (2012). An analysis of 

the applicability of material property testing to similar projects is covered in an upcoming BSC 

report, which examines test results with other variables such as project geographic location, 

vintage, and other readily available properties (density, water uptake). 

BEoptTM parametric analysis was performed for insulation options for the wall retrofit in order to 

determine the energy performance for each wall system and the most cost effective measure. The 

project team decided to explore the following options for the wall retrofit: three layers of 2-in. 

extruded polystyrene (XPS) rigid insulation, two layers of 2 in. XPS rigid insulation, 5 in. of 

closed-cell spray polyurethane foam, and 2 in. of closed-cell spray polyurethane foam with batt 

insulation. Advantages and disadvantages of each wall system were explored. 

The proposed 6-in. XPS rigid insulation on the interior of the masonry was selected as one of the 

best performing options. The energy analysis determined this option is not the most costeffective measure; however, it was selected due to the financial model of Habitat for Humanity, 

which includes volunteer labor and donated materials. 

The cost of a project typically increases with the improved performance, but local incentives and 

state and federal tax credits can offset some of the cost. Energy analysis can be used to let 
xi 

homeowners and builders select the most suitable and feasible measures. These results determine 

what level of efficiency can be achieved within budget constraints. REM/Rate energy analysis 

software was used to determine the predicted energy savings for each housing unit by 

implementing the advanced retrofit packages. This work was driven by Massachusetts incentives 

of more than $1000/unit (ENERGY STAR Qualified Homes, Version 3 Tier II). 

Effective air barriers are an important component for good energy performance, good indoor air 

quality, and control of interstitial condensation. In addition, an effective air barrier between units 

of multifamily housing reduces transmission of sound, odors, and smoke, lowers fire spread risk, 

and helps control stack-driven airflows. Therefore, BSC established targets for air barrier and 

compartmentalization performance on this project, and developed multiple details for 

airtightness (interior-to-exterior) and compartmentalization (unit-to-unit) strategies. 

The planned research is intended to analyze the effectiveness of air barrier strategies 

implemented in this multifamily retrofit; however, no units have been completed to date, so 

effectiveness has not yet been measured. However, some information is available on the 

secondary question, of the difficulties in implementing these air barrier details. 

Use of individual unit space heating and domestic hot water systems greatly limits the 

distribution losses associated with these systems, at a comparable or lower net cost to centralized 

systems. The use of individual unit heat recovery ventilator (HRV) systems greatly improves 

compartmentalization, and based on preliminary analysis, provides substantial first cost savings 

relative to a large centralized HRV system. Use of individual tankless water heaters and HRV 

units in each condominium will also provide the homeowners with the ability to control the 

settings according to their particular lifestyles and desired comfort levels. Therefore, BSC 

developed a mechanical design with individual mechanical systems for each apartment unit, and 

for the common areas of the MVHfH multifamily building. However, no mechanical systems 

have been installed to date, nor have any quotes been received for the design. Therefore, the cost 

impacts cannot be determined at this point, but details on the current heating, ventilation, and airconditioning design are available. 

BEopt software was used to evaluate the cost effectiveness of the retrofit measures proposed 

for this project as well as the predicted site energy use. One representative unit was chosen for 

energy modeling (Unit 8, on the second floor). Several options for wall insulation, window 

types, air leakage, and mechanical systems were modeled in order to determine the combinations 

of measures that are the most cost effective. The difference in source energy use between 

the “Existing” and “Minimum Cost Case” projected by BEopt was 95.0 MBtu/yr, or a 52.6% 

reduction. However, the “Design Case,” which generates a slightly higher reduction 

(96.2 MBtu/yr or 53.3%) but at a higher cost (per BEopt), was chosen by the design team. This 

case includes measures that are the best approaches for this particular project and may not be the 

most cost effective in all cases because of the financial model of Habitat for Humanity.

The retrofit work on the apartment units is ongoing and the project is slated for a completion date 

in December of 2014. Therefore, the utility bills were not available for the comparison of the 

predicted and actual energy use. No additional work is planned for this project in the subsequent 

years due to the termination of funding at the end of 2012. 
1 

1 Introduction

Merrimack Valley Habitat for Humanity (MVHfH) has partnered with Building Science 

Corporation (BSC) to provide high performance affordable housing for 10 families in the retrofit 

of an existing brick building (a former convent) into condominiums. 

The research performed for this project provides information regarding advanced retrofit 

packages for multifamily masonry buildings in cold climates. In particular, this project 

demonstrates safe, durable, and cost-effective solutions that will potentially benefit millions of 

multifamily brick buildings throughout the East Coast and Midwest (cold climates). The retrofit 

packages provide insight on the opportunities for and constraints on retrofitting multifamily 

buildings with ambitious energy performance goals but a limited budget. 

The condominium conversion project will contribute to several areas of research on enclosures, 

space conditioning, and water heating. Enclosure items include insulation of mass masonry 

building on the interior, airtightness of these types of retrofits, multiunit building 

compartmentalization, window selection, and roof insulation strategies. Mechanical system items 

include combined hydronic and space heating systems with hydronic distribution in small (low 

load) units, and ventilation system retrofits for multifamily buildings.

This report is divided into the following sections: 

• Evaluating the risks of freeze-thaw (FT) to the masonry walls and identifying the 

suitability of the building for retrofit of insulation

• Exploring several wall retrofit strategies to determine the most cost-effective solution that 

will achieve specific thermal performance

• Energy analysis to determine the incentive levels the project is able to qualify for 

• Development of specific guidance on establishing an air barrier for each of the housing 

units in the building, as well as identifying difficulties in developing robust air sealing 

and compartmentalization details for the proposed wall retrofit design and their 

implementation

• Comparison of the cost and performance of the proposed measures to be implemented on 

the project.

The following research questions were covered in this project: 

• Does the addition of high levels of interior insulation present a risk of FT damage to the 

mass masonry walls in this building?

• What are the predicted energy performance and cost impacts of the proposed wall retrofit 

design (6 in. of extruded polystyrene [XPS]) versus the other considered strategies (spray 

foam, flash, and batt)? 
2 

• How do rebates and incentives impact the decision-making process of the builder, 

especially in cases of budget-constrained construction projects? In addition, how do these 

impact the overall energy performance?

• What is the effectiveness of air barrier strategies implemented in this multifamily retrofit 

project, and what were the difficulties in implementation?

• What are the cost impacts of implementing a compartmentalized ventilation strategy with 

individual apartment heat recovery ventilator (HRV) systems versus a traditional large 

single central HRV system?

• What are the cost impacts of using individual unit combination space heating/hot water 

units, including distribution piping design and installation specifics? 

• How does the actual energy performance (i.e., utility bills) compare to the BEopt 

predicted site energy use? 

Background

The former St. Patrick Convent (Figure 1) was purchased by MVHfH from the City of Lawrence 

in early 2008 for $300,000. The building consists of two parts: the original building (circa 1906 

construction) and a rear addition (circa 1930 construction); a small third addition was

demolished as part of the renovation (Figure 2). The building was divided into 10 three-bedroom 

units with designated common meeting and storage spaces. The sale price for the three-bedroom 

units is predicted to be between $125,000 and $130,000 with 35-year mortgages.

Figure 1. MVHfH retrofit building in Lawrence, Massachusetts
3 

Figure 2. MVHfH retrofit building aerial views

The total budget for the project has been set for $1 million. The project heavily relies on the 

donated materials as well as volunteer labor, but there are several components of the retrofit that 

require various industry professionals, such as roofers, electricians, plumbers, heating, 

ventilation, and air-conditioning (HVAC) technicians, and brick repair contractors.

The original plan for the project was a “phased” approach, completing contiguous blocks of units 

in groups. The plan was to have three phases: three units and the common space in Phase I, four 

units in Phase II, and the last three units (located in the addition) in Phase III.

However, the project team is now seeking a loan from the Federal Home Loan Bank of Boston 

for the amount of $200,000, and the terms of the loan dictate the completion date in December 

2014. Dividing the project into phases would slow the schedule, because it would require the 

team leaders to teach volunteers the same skills in all three phases, and coordinate the work with 

the different trades. The final decision on phasing the project has yet to be made.

Before the building was acquired by MVHfH, it had been left vacant and unheated for two or 

three years. After purchase, the interior of the building was completely gutted, including all 

HVAC, plumbing, electrical, partition walls, and interior finishes. There were several issues that 

needed to be addressed with this retrofit project before proceeding with the installation of the 

high performance and energy-efficient measures. Repair and remediation of structural members 

took priority and have been completed. Structural issues associated with the settling of brick 

walls were evaluated by a Boston-based structural firm, and are being addressed as well. The 

roof leak in the rear addition also has been addressed before proceeding with any interior work in 

that area of the building. 

The original energy-efficient retrofit goals for the project were to provide an R-60 roof, R-40 

above-grade walls, R-20 basement walls, R-10 basement slab, and R-5 windows, as promulgated 

by National Grid (2011), and similar to targets proposed by Straube (2011). The building section 

shown in Figure 3 illustrates the retrofit approaches to be implemented on this project.

Addition Existing 

Building

Demolished
4 

Figure 3. MVHfH building section
5 

2 Brick Material Property Testing and Hygrothermal Simulations

One of the initial questions in this renovation project was whether the existing mass masonry 

walls could be retrofitted with insulation without durability problems (see Straube et al. 2012). 

To understand these risks, the team performed a site assessment (documented in Appendix A), 

followed by material property testing and hygrothermal simulations. The latter two tasks

involved laboratory testing of sample bricks, and hygrothermal computer simulations to diagnose 

the cause of current issues and predict the effect of potential interior insulation retrofit. This 

section includes a summary of the material property testing results, a description of the 

hygrothermal computer simulations, and an interpretation of the results.

The brick samples were collected from the building by BSC staff during a site visit on August 3, 

2011. Two brick samples each were collected from the interior and exterior of the original and 

addition sections of the building (for a total of eight). These bricks were taken directly from the 

wall assembly. Additional samples were also taken, which were sitting on the roof and part of a 

small demolition of an added structure. These additional samples were not used since their origin 

could not be determined. 

Material Property Testing

The brick samples were subjected to a series of material property tests to facilitate the 

hygrothermal simulations and inform the assessment of FT risk. The material properties, test 

method, and results are summarized in the sections that follow. Further information on the 

testing procedures can be found in Straube et al. (2012). 

Dry Density

Dry density is a fundamental material property that is used as a basic input for all hygrothermal 

simulation programs. Dry density is used to predict how much heat and moisture are stored in a 

material over a given time period.

To determine dry density, the brick samples are dried in a gravity oven and periodically weighed 

using a precision scale. Drying continues until there is no longer any change in mass. This 

process can take many days to complete. The volume of each brick sample is then determined 

using a liquid displacement method. The dry density is simply the quotient of the dry mass and 

the volume. The test results are given in Table 1. 

Water Absorption or Uptake Coefficient (A-Value)

The water absorption coefficient or uptake (Aw or A-value) characterizes the capillary uptake of 

the material. The value is used in hygrothermal simulation programs to predict the movement of 

liquid water under capillary suction and redistribution. 

The liquid water uptake test follows the method set out in DIN 52617. Carefully cut and ovendried brick “chunks” (approximately half a brick in size) are placed so that their exposed faces 

(i.e., the outside faces of the bricks) are just in contact with a pool of water. The samples are 

periodically removed from the water, weighed using a precision scale, and placed back in contact 

with the water surface. The measured mass is plotted against the square root of the time of the 

measurements and normalized for cross-sectional area. The A-value is determined from the slope 

of this graph and has the rather unusual units of lb/in.2s1/2. The test results are given in Table 1. 
6 

Free Water Saturation

The free water saturation is practical maximum moisture content for masonry units in the field.

Higher moisture contents can be reached only in the presence of dissolved salts or conditions that 

would cause condensation to occur within the empty pores. The value is part of the information 

used in hygrothermal simulation to estimate the relationship between moisture storage and 

relative humidity for the masonry units. 

The free water saturation values were approximated from cold soak moisture contents. This is 

the moisture content of the brick after being left in a laboratory temperature water bath for 24 

hours. The test results are given in Table 1. 

Vacuum Saturation

The vacuum saturation moisture content is used to estimate the maximum amount of moisture 

that can be held in the brick when all of its open pores are filled with water (Wmax). This 

characteristic value is used to determine the degree of saturation when assessing the resistance to 

FT action. 

Carefully cut brick “slices” (approximately 10 mm or 3⁄8 in. in thickness) are oven-dried, then 

placed in a desiccator, and a vacuum pump is used to remove any remaining water vapor 

molecules and 99.9% of the air. The vacuum pump is shut off and water is supplied to the 

desiccator. Nearly 100% of the open pores in the material are filled with water in this process.

The brick slices are said to be “vacuum saturated.” The vacuum saturation moisture content is 

the difference of the mass of the water when saturated and the mass of the dry sample. The test 

results are given in Table 1. 

Critical Degree of Saturation

The critical degree of saturation (Scrit) is the moisture content at which the material becomes 

susceptible to FT damage. The degree of saturation is the fraction of saturation relative to 

complete vacuum saturation. For example, at 0.5 degrees of saturation, the brick contains 50% of 

the moisture that it would at vacuum saturation. Fagerlund (1977) showed that below some Scrit, 

no FT damage is possible, regardless of the number of temperature excursions below freezing. 

Similarly, very few freezing cycles are needed to cause damage if the moisture content is above 

Scrit. 

Brick slices are carefully prepared to present clean measurement surfaces. The pretest length of 

each slice is measured using a precision micrometer. The slices are then brought to various 

degrees of saturation (0.7, 0.8, 0.9, etc.) and sealed in packaging so that moisture does not enter 

or escape. The sealed slices are allowed to “rest” for several hours so that internal moisture can 

distribute uniformly throughout each slice. The slices are then immersed in a controlled 

temperature bath and subjected to at least six FT cycles. The slices are brought back to room 

temperature and removed from the bath. The posttest length is measured, and the change in 

dimension or dilation is used to identify FT damage. Numerous tests are performed on slices 

from each brick sample to facilitate an estimate of Scrit. The test results are given in Table 1. 
7 

Table 1. Brick Material Property Testing Results

Sample

24-h Cold 

Soak

Moisture 

Content by

Weight

5-h Boil

Moisture 

Content

by Weight

Dry 

Density 

per 

cubic 

foot

A-Value

lb/ft2

s

1/2

Vacuum 

Saturation

(per cubic 

foot) 

Scrit

%Vacuum 

Saturation

Original Building, 

Exterior 1 5% 7% 130 0.0103 13 NA

Original Building, 

Exterior 2 3% 4% 155 0.0058 15 0.80

Original Building, 

Interior 1 3% 3% 179 0.0075 17 0.80

Original Building, 

Interior 2 2% 2% 99 0.0079 9 0.80

Addition Building, 

Exterior 1 4% 5% 118 0.0066 11 NA

Addition Building, 

Exterior 2 3% 3% 145 0.0037 13 0.75

Addition Building, 

Interior 1 3% 6% 135 0.0013 12 0.85

Addition Building, 

Interior 2 3% 3% 136 0.0021 12 0.75

These results can be put in context with qualitative descriptions by Lstiburek (2010), who 

considered “poor” Scrit values to be in the 0.4 or lower range, and “good” Scrit values to be in the 

0.8 or higher range. The results appear to indicate good FT resistance for the tested brick.

Several of the Scrit values are listed as “NA.” In those cases, the sample dilation at high moisture 

content was below the repeatability range of the length measurement. In other words, the 

expansion of the sample after FT cycling was too small to be measured effectively. Although 

these results are inconclusive, an interpretation could be that it suggests the brick is more 

resistant to FT cycling damage.

Hygrothermal Simulations

The Wärme und Feuchte Instationär (WUFI) hygrothermal computer simulation model was used 

to simulate the effects of insulating the walls on the moisture and temperature conditions of the 

masonry walls. WUFI is one of the most advanced commercially available hygrothermal 

moisture programs in use today. Its accuracy has been verified (by the Fraunhofer-Institut für 

Bauphysik in Holzkirchen, Germany) against numerous full-scale field studies of enclosure 

performance (roofs, walls, foundations, parking garage decks, etc.) over a number of years.

Much of the field verification work supporting the model has been solid masonry wall systems.

WUFI is one of the few models in the public domain that can properly account for rain 

absorption and different water absorption and redistribution for arbitrary material data and 

boundary conditions. Given the appropriate material data, WUFI calculates heat and moisture 

flow every hour under the influence of sun, rain, temperature, and humidity. The analysis is, 
8 

however, only as accurate as the assembly data, the material properties, and the interior and 

exterior conditions input.

Air Leakage

The WUFI computer model has the capacity to predict interstitial air leakage-induced wetting 

and drying; however, we have not made use of this feature because the leakage path and driving 

forces are unknown, and are generally unique. The time scale of wind-induced air leakage is also 

much shorter than 1 h. Note that this is specifically leakage of air from the interior into the 

insulated assembly (e.g., into the interface between the insulation and the masonry, causing 

condensation). This does not address the larger energy topic of interior-to-exterior air leakage.

In all of the cases studied in this project, it has been assumed that air leakage across the 

enclosure has been essentially controlled using appropriate air sealing materials and techniques, 

such as using interior spray foam insulation. It would be highly risky to design a retrofit that 

allows a significant amount of air leakage. However, experience has shown that air barrier 

systems formed by careful taping, caulking, use of spray polyurethane products, and fully

adhered membranes are quite likely to achieve airtightness when properly installed using 

standard quality control measures.

Climate Data

WUFI includes climate data files for dozens of cities around the world. These climate files are 

typically generated from airport or other major weather station data. For the purposes of the 

Merrimack Valley Habitat for Humanity simulations we have used the Boston “cold” year 

weather file that is included in WUFI, summarized in Figure 4 and Figure 5. The existing interior 

conditions were simulated assuming heating only, as shown in Figure 6. 

Figure 4. WUFI 5.1 Pro temperature and humidity for a “typical” cold year in Boston
9 

Figure 5. WUFI 5.1 pro climate summary for a “typical” cold year in Boston

Figure 6. Indoor conditions used in WUFI simulation (temperature and relative humidity) 
10 

Material Properties

It is often not convenient (or even possible) to determine the many material properties necessary 

for hygrothermal simulations, so WUFI includes a database of several hundred common 

materials. However, hygrothermal computer simulations are only as reliable as their input data, 

and it is advisable to measure and use key material properties whenever this can be practically 

done. 

For the purposes of the MVHfH simulations, we have derived the key masonry properties from 

laboratory testing and used existing data from the WUFI database for the remaining masonry 

properties and for other materials. 

Assessing Freeze-Thaw Degradation Risk

The FT degradation risk is assessed by predicting the masonry moisture content during incidents 

when the material temperature drops below 23°F (–5°C). The moisture content levels are plotted 

in a histogram and compared to range of Scrit values found in our laboratory testing. For the 

middle bricks, only one sample was provided, so we are assuming a similar range of Scrit as the 

exterior bricks.

Within the masonry industry, physical pass-fail testing of individual bricks is commonly 

considered to be the best measure, despite the fact that the ASTM and Canadian Standards 

Association standards often rejects bricks found from experience to be durable and sometimes 

accepts bricks that fail in the field (Vickers 1993; Arnott and Maurenbrecher 1990; Robinson et 

al. 1995). The approach used in this study is more intensive but provide a more accurate and 

exposure-specific assessment of FT degradation risk.

Enclosure Assemblies Modeled

Figure 7 shows the WUFI model for the typical existing masonry enclosure wall assembly in the 

original building sections of 100 Parker Street. The various materials used in the wall assembly 

are represented by different colors. In this image, one can see the red clay exterior brick, 

followed by a layer of gray mortar, the two interior brick wythes, and mortar layers. The wall 

assembly modeled for the addition section of the building has hollow clay tile replacing the two 

interior wythes, as shown in Figure 8. The clay tile is shown with thin outer layers (beige) and an 

interior cavity (blue).
11 

Figure 7. WUFI model of existing original building masonry wall assembly (solid brick wythes)

Figure 8. WUFI model of existing addition masonry wall assembly (hollow clay tile backup)

The addition of 6 in. of XPS foam board and drywall was evaluated for both wall assemblies as 

shown in Figure 9 and Figure 10. 

■ Face Brick ■ Fill Brick ■ Mortar

■ Face Brick ■ Clay Tile ■ Air Space ■ Mortar
12 

Figure 9. WUFI model of addition masonry wall assembly with insulation retrofit

Figure 10. WUFI model of original building masonry wall assembly with insulation retrofit

Within these models the exterior face brick is divided into four volumes with relatively thin inner 

and outer layers as shown. A 5-mm (~1⁄4-in.) volume was modeled at the exterior of the face 

brick. Just inside of this a 10-mm (~3⁄8-in.) thick subsurface volume was modeled. This is often a 

location where FT damage is observed. Next, another 10-mm (~3⁄8-in.) volume was modeled at 

the interior (i.e., back) of the face brick. Two layers were modeled in the backup brick: one 10-

mm (~3⁄8-in.) volume at the exterior and interior faces of the outer backup brick or the tile. 

In each case the potential for FT is assessed by considering the predicted hourly moisture content 

and temperature for each study volume. 

Hygrothermal Simulation Results

The simulation results for the existing original building and the addition wall assemblies are 

plotted in Figure 12 and Figure 13. These simulations were repeated for the same wall 

assemblies and exposures after insulation, as plotted in Figure 14 and Figure 15. The multiple 

column graphs correlate with key vulnerable layers within the masonry assembly, as shown in 

Figure 11. 

■ Face Brick ■ Fill Brick ■ Mortar ■ Spray Foam ■ Gypsum Board

■ Face Brick ■ Clay Tile ■ Air Space ■ Mortar ■ Spray Foam ■ Gypsum 

B d
13 

Figure 11. Example moisture content plot, correlated with assembly layers 

Within the plots, the moisture content is expressed in degrees of saturation (i.e. fraction of 

vacuum saturation). The column in the graph represents the number of hours (during freezing) 

that the moisture content in the control volume is predicted to be between 0 and 0.1 degrees of 

saturation; the second column represents hours between 0.1 and 0.2 degrees of saturation; the 

column space hours between 0.2 and 0.3 degrees of saturation, and so on. Note that the 

frequencies are plotted on a logarithmic scale.

The blue shaded areas on the right of the plot show the lower and upper bounds of the Scrit (i.e., 

the moisture content above which damage is predicted to occur should temperatures cycle below 

some freezing threshold—usually 23°F or –5°C). The left edge of the light blue shaded area 

represents the lowest estimate of Scrit from the brick samples tested, while the left edge of the 

dark blue shaded area represents the highest estimate. The potential for FT damage is greatest 

when the predicted moisture content exceeds the Scrit during freezing. On these graphs this would 

be represented by hourly distribution columns in the shaded zone. 

Exterior Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Sub Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Interior Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Exterior Face of Backup Brick (Wythe 2)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Interior Face of Backup Brick (Wythe 2)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours
14 

No FT cycles are predicted for any of the simulated conditions. However, the cases with the 

thermal insulation retrofit generally show greater moisture contents during freezing conditions. 

Previous simulations of many other mass masonry buildings indicate that the exterior layers of 

the exterior brick are the most vulnerable, and that greater rain exposure increases risk. The 

pattern of damage on the building generally correlated with rain exposure, such as damage at 

areas around missing downspouts. It is assumed that these areas are seeing much greater rain 

exposure than predicted in the model. It should be noted that addressing the rainwater 

management issues associated with the existing areas of damage must be addressed, as the 

thermal insulation retrofit will exacerbate such problems. 

Conclusions

The material property testing and hygrothermal simulations conducted for the MVHfH project 

indicate the following:

• In both simulated wall assemblies, at normal rain exposures, brick FT risk is predicted to 

be minimal with or without the thermal insulation retrofit.

• The existing brickwork damage is likely due to the combination of rainwater 

concentrations due to poor maintenance and details (e.g., gutter/downspout failures). 

• The rainwater management issues associated with the existing areas of damage must be 

addressed, as the thermal insulation retrofit will exacerbate such problems. 
15 

Figure 12. Predicted moisture distribution during freezing temperatures: 

existing original building wall assembly, normal exposure, east facing, heating only

Exterior Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Sub Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Interior Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Exterior Face of Backup Brick (Wythe 2)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Interior Face of Backup Brick (Wythe 2)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Wall assembly Original (solid brick)

Wall condition Uninsulated

Orientation East

Rain exposure Normal

Int. conditions Heated
16 

Figure 13. Predicted moisture distribution during freezing temperatures: 

existing addition wall assembly, normal exposure, east facing, heating only

Exterior Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Sub Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Interior Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Exterior Face of Backup Brick (Wythe 2)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Interior Face of Backup Brick (Wythe 2)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Wall assembly Addition (clay block)

Wall condition Uninsulated

Orientation East

Rain exposure Normal

Int. conditions Heated
17 

Figure 14. Predicted moisture distribution during freezing temperatures: 

retrofit original building wall assembly, normal exposure, east facing, heating only

Exterior Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Sub Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Interior Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Exterior Face of Backup Brick (Wythe 2)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Interior Face of Backup Brick (Wythe 2)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Wall assembly Original (solid brick)

Wall condition Insulated 6 in. XPS

Orientation East

Rain exposure Normal

Int. conditions Heated
18 

Figure 15. Predicted moisture distribution during freezing temperatures: retrofit addition wall 

assembly, normal exposure, east facing, heating only

Exterior Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Sub Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Interior Layer of Face Brick (Wythe 1)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Exterior Face of Backup Brick (Wythe 2)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Interior Face of Backup Brick (Wythe 2)

1

10

100

1,000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Degree of Saturation

Hours

Wall assembly Addition (clay block)

Wall condition Insulated 6 in. XPS

Orientation East

Rain exposure Normal

Int. conditions Heated
19 

3 Predicted Energy Performance and Cost Impacts of Proposed 

Wall Retrofit Design

Upon the completion of the FT analysis, the project team began to work through all of the 

possible choices for the wall retrofit. There were a number of suitable insulation options for this 

masonry building, including: XPS rigid insulation, closed-cell spray foam (ccSPF), or a hybrid 

approach of ccSPF or XPS with fiberglass batt or cellulose insulation.

Both the strict budget and the energy performance goals were important factors driving this 

extensive retrofit. The project team considered a number of key items while selecting the wall 

system, such as the cost of materials and labor, constructability of the system, as well as the 

performance aspects of each option. 

Wall Retrofit Options

The project team examined the following options for the wall retrofit; R-values are summarized 

in Table 2. 

• Three layers of 2-in. XPS rigid insulation (2 × 4 stud wall inboard of insulation) 

• Two layers of 2-in. XPS rigid insulation (2 × 4 stud wall inboard of insulation) 

• 5 in. of ccSPF (2 × 4 stud wall inboard of insulation) 

• 2 in. of ccSPF with 5.5-in. fiberglass batt (fiberglass in 2 × 6 stud wall inboard of ccSPF). 

There are advantages and disadvantages associated with each wall system. The benefit of using 

the XPS rigid insulation in this specific case is that both material and labor are free. The MVHfH 

team secured a donation from Dow Chemical Company for the rigid foam, as well as the 

adhesive used for attaching the foam to the masonry walls (further discussed in Section 4 of the 

report). As a Habitat for Humanity organization, the labor is provided by unpaid volunteers. The 

disadvantage of using rigid sheet goods (such as XPS) compared to a monolithic material (such 

as spray foam) is the challenge of establishing a continuous air barrier, as well as the 

implementation of the drawn details. Also, given that the work is carried out by volunteers, the 

construction process is significantly slower. 

Spraying 5 in. of ccSPF onto the masonry walls will contribute to the airtightness of the 

assembly and will result in excellent condensation and vapor diffusion control. The work has to 

be performed by an industry professional and can, therefore, be completed in a shorter amount of 

time. The drawback, however, is the cost of material and labor. 

The option of spraying 2 in. of ccSPF and installing batt insulation in the wall cavities creates a 

“hybrid” assembly that uses each material to its best advantage. The spray foam creates a robust 

air barrier and controls interstitial condensation risks, while the batt insulation is a more 

affordable product that raises the R-value of the assembly. However, the disadvantage is, again, 

the cost of materials for both the ccSPF and the fiberglass insulation. Volunteers are able to 

install the fiberglass batt insulation, but the spray foam insulation must be installed by a 

professional. 
20 

BEopt Parametric Analysis

In order to provide an economic analysis that is representative of a typical construction market, 

the BEopt analysis for this project was performed. BEopt, the Building America performance 

analysis tool, which features options for retrofit projects, was used to analyze the energy use and 

the cost effectiveness of the wall retrofit measures considered for this project.

One representative apartment unit was chosen for energy modeling: Unit 8 located on the second 

floor of the rear addition (Figure 16). This particular unit was selected because of its simple 

geometry as well as its exposure to the exterior. 

Figure 16. Unit 8 floor layout

Using the parametric feature in BEopt, alternate options for wall insulation were modeled in 

order to determine the energy performance for each option and the most cost-effective measure. 

The default cost values for the Chicago Retrofit (a BEopt default library) were used for the 

majority of the inputs. Several cost values were obtained from RSMeans Reed Construction Data 

2012 (Reed 2012), a cost-estimating tool, which provides the cost of materials, installations as 

well as overhead and profit. The cost of windows per unit was derived from the estimate 

provided by Harvey Industries. The utility rates used were the state average values for 

Massachusetts provided by BEopt. 

Table 2 lists four options for the exterior wall insulation that were selected for the comparison: 6 

in. of XPS rigid insulation, 4 in. of XPS rigid insulation, 5 in. of ccSPF, and 2 in. of ccSPF with 

fiberglass batt insulation. The values include cost of materials, labor, and profit. The R-values 

listed in Table 2 were derived from the BEopt model. 

To simulate multifamily boundary conditions, an adiabatic crawlspace (with R-100 floor cavity 

insulation) and an attached unit wall on the southwest side were used in the modeling. A flat roof 

with 6 in. of XPS rigid insulation and 6 in. of ccSPF (R-66), and new ENERGY STAR-qualified 
21 

double-pane window units (U = 0.30, solar heat gain coefficient [SHGC] = 0.30) were listed in 

the inputs. A gas boiler with 91% efficiency was also listed. For the infiltration rate of 1.7 

ACH50 was used for all of the options; in addition, the two options that feature the ccSPF 

insulation were modeled again with an air leakage of 1.2 ACH50. The rate was adjusted to 

reflect the reduction in air leakage by using ccSPF as compared to the other packages.

Table 2. BEopt Energy Modeling Inputs for Wall Retrofit Options

Point Wall Retrofit Options R-Value ACH50 RSMeans 

Cost Values

1 6 in. XPS with 2 × 4 stud wall 31.5 1.7 $9.46/ft2

2 4 in. XPS with 2 × 4 stud wall 22.6 1.7 $7.47/ft2

3 5 in. ccSPF with 2 × 4 stud wall 31.1 1.7 $7.53/ft2

4 2 in. ccSPF + 5.5 in. fiberglass batt with 2 × 6 

stud wall 30.4 1.7 $5.92/ft2

5 5 in. ccSPF with 2 × 4 stud wall 31.1 1.2 $7.53/ft2

6 2 in. ccSPF + 5.5 in. fiberglass batt with 2 × 6 

stud wall 30.4 1.2 $5.92/ft2

Results

Wall Retrofit Energy Performance

Figure 17 shows the average source energy use (MBtu/yr) for the selected four wall systems 

generated by BEopt. The results indicate that options 1 (6 in. XPS rigid insulation), 3 (5 in. 

ccSPF), and 4 (2 in. ccSPF with batt insulation) use essentially the same amount of energy. 

Option 2 (4 in. XPS rigid insulation) uses 1.4 MBtu/yr (~2%) more than the proposed 6 in. XPS 

rigid insulation. These results were expected, as the R-values of options 1, 3, and 4 are 

comparable. The reduced air leakage for Points 5 and 6 improved the energy usage minimally. 

Figure 17. Unit 8 BEopt parametric results—average source energy use
22 

Wall Retrofit Cost Analysis

The results of the energy modeling also indicate that the wall system selected for this project is 

not the most cost-effective option (Figure 18). Specifically, the cost-optimized wall system based 

off market rates for labor and materials would be 2 in. ccSPF to the interior face of the masonry 

wall, with 5.5 in. fiberglass batt insulation in a 2 × 6 framed wall. 

Figure 18. Unit 8 BEopt parametric results—minimum cost

Cost benefit calculations are complicated by the financial model of Habitat for Humanity, which 

includes free (volunteer) labor, some donated materials, and other materials at market rates. This 

can result in some distortions that result in practices that may not be the most cost effective in all 

cases, but are the best approach for this particular project. 

The wall assembly for this project is a representative example of such cases. Specifically, 

although fiberglass insulation is less expensive than XPS on a $/R∙ft2 basis, donated (free) XPS 

was less expensive than fiberglass insulation, which would need to be purchased at market rates. 

Therefore, 6 in. XPS rigid insulation on the interior of the masonry wall was selected, due to 

volunteer labor and donated materials. 

BEopt Most Cost-Effective Wall Option

The combination of the ccSPF and batt insulation creates a highly insulated wall (R-30 nominal) 

at a reasonable cost (Figure 19). The ccSPF is a high-priced material that requires professional 

application, but it offers multiple benefits. The material has a high R-value per inch, creates a 

robust air barrier, and controls condensation risks (at sufficient thicknesses). The fiberglass batt 

insulation, which is significantly cheaper, is easy to install, increases the R-value for the entire 

assembly, and utilizes the wood framing cavity (unlike the installed wall). This creates an 

affordable option that is suitable for a majority of mass masonry buildings in a cold climate. 

However, the suitability of the masonry wall for the retrofit of interior insulation must be 

determined, including improvement of bulk water shedding details, and determination of brick 

material properties (as per Straube et al. 2012).

6 in. XPS

5 in. 

ccSPF

2 in. ccSPF + 5.5 in. FG

4 in. XPS
23 

Figure 19. BEopt most cost-effective wall option—2 in. ccSPF + 5.5 in. fiberglass batt
24 

4 Impact of Rebates and Incentives on Decision-Making Process

National Grid Deep Energy Retrofit Pilot Program

MVHfH and BSC began their collaboration through the National Grid Deep Energy Retrofit 

Pilot Program (National Grid 2011), which provides financial incentives and technical support to 

participants. The program’s goal is ideally to achieve at least 50% better energy performance 

than a code-built home. BSC has partnered with National Grid, providing technical guidance and 

support for the program. 

The project team was interested in submitting an application to the program in order to qualify 

for the incentives; however, it was later determined that National Grid was neither the gas nor 

the electricity provider for the building. Even though the project was not able to participate in the 

program, the enclosure retrofit goals of providing an R-60 roof, R-40 above-grade walls, R-20 

basement walls, R-10 basement slab, and R-5 windows remained part of the retrofit strategy for 

the building. 

ENERGY STAR-Qualified Homes

Program Information

The project is pursuing the ENERGY STAR certification for each of the apartment units through 

the ENERGY STAR Qualified Homes, Version 3 program. Eligible homes or units are able to 

obtain the certification through either the Prescriptive or the Performance Path.

The program requirements for climate zone 5 are as follows (Mass Save 2012):

• Cooling equipment shall have a seasonal energy efficiency ratio (SEER) rating ≥ 13; or 

for air source heat pumps with 14.5 SEER; all cooling equipment must be sized 

according to the latest editions of Air Conditioning Contractors of America (ACCA) 

Manuals J and S, ASHRAE 2001 Handbook of Fundamentals, or an equivalent 

computation procedure; the maximum oversizing limit for air conditioners is 15%, 25% 

for heat pumps; documentation must be provided to the Home Energy Rating Systems 

(HERS) Rater.

• Heating equipment shall have ≥ 90 annual fuel utilization efficiency (AFUE) gas furnace; 

85 AFUE oil furnace; 85 AFUE boiler or an air source heat pump with 9.25 heating 

season performance factor/14.5 SEER/12 energy efficiency ratio with electric backup. 

• Ventilation—at least one of the following devices must be installed: one bath fan rated 

for continuous use < 1.5 sones and controlled by a 24-h programmable timer; or one 

whole-house mechanical ventilation system; or a balanced supply and exhaust system 

without heat recovery; or a multiport exhausts only system with a remote mounted fan. 

• Envelope—insulation levels shall meet or exceed 2009 International Energy 

Conservation Code levels and achieve Grade I installation per Residential Energy 

Services Network (RESNET) standards.

• Infiltration rate shall be determined by a rater using a RESNET-approved testing 

protocol. 

• Windows shall have U-value 0.30 and any SHGC. 
25 

• Doors—opaque: 0.21 U-value, no SGHC Rating; ≤ 1⁄2 lite: 0.27 U-value, 0.30 SHGC; > 

1⁄2 lite: 0.32 U-value, 0.30 SHGC. 

• Water heater—installed heating and domestic hot water (DHW) systems must generate 

positive energy savings. 

• Thermostat—programmable thermostats shall be installed unless the thermostat controls 

a zone with electric radiant heat.

• Ductwork—supply ducts in unconditioned space shall have insulation < R-8; all other 

ducts in unconditioned space shall have insulation < R-6; total duct leakage shall be < 8 

CFM25/100 ft2 of conditioned floor area; duct leakage to outdoors shall be < 4 

CFM25/100 ft2 of conditioned floor area. 

• Lighting—ENERGY STAR-qualified light bulbs or fixtures shall be installed in 80% of 

RESNET-defined qualifying light fixture locations. 

• All installed appliances must be ENERGY STAR qualified.

There are three incentive levels within the program, Tiers I, II, and III (Table 3). All tiers have to 

achieve a certain percentage savings above the User Defined Reference Home. The energy 

savings for each tier have associated incentive amounts that builders are able to receive for 

qualified projects.

Table 3. ENERGY STAR Tier Levels

Tier Level Percent Savings Incentive Amount for Multifamily 

(2–99 Units)

Tier I 20% $650

Tier II 30% $1,150

Tier III 45% $4,000

Building Energy Analysis

Part of the ENERGY STAR certification process is to determine the HERS Index Target for each 

of the units. A RESNET-certified HERS rater, hired by the project team, performed the energy 

analysis for the building with the REM/Rate software package, which was created by 

Architectural Energy Corporation. 

Four representative units were modeled to calculate estimated energy savings of the proposed 

measures. Unit 2 is located in the basement of the addition, Unit 3 is located on the first floor of 

the original building, Unit 8 is located on the second floor of the addition and Unit 9 is located 

on the third floor of the original building. The four units selected for the analysis have different 

geometries as well as solar exposures. Enclosure and equipment specifications listed in Table 4

were used as inputs for the energy modeling. 
26 

Table 4. REM/Rate Energy Modeling Inputs

Component Characteristics

Roof—Flat 6 in. XPS plus 6 in. ccSPF

Roof—Sloped 6 in. ccSPF in rafter cavity

Wall 6 in. XPS inboard of masonry, with stud frame wall

Basement Wall 3–31⁄2 in. ccSPF

Basement Slab 2 in. XPS

Windows New double-glazed vinyl windows 

U = 0.30, SHGC = 0.30

Infiltration 2.0 ACH50

Heating and Cooling

Gas-fired tankless water heater (91% CAafue or combined 

appliance AFUE) per unit, with baseboard radiation 

heating loop; no cooling provided

DHW Gas-fired tankless water heater, per unit

Ventilation HRV, individual units (50% of ASHRAE 62.2)

Lighting 100% compact fluorescent lamps (CFLs)

Appliances ENERGY STAR refrigerator, dishwasher, clothes washer

Table 5 summarizes the potential energy savings, HERS rating and whether or not the unit 

qualifies for ENERGY STAR Qualified Homes, Version 3 Tier II incentives. Detailed reports 

showing calculations of heating, cooling, hot water, lighting and appliance energy loads for the 

selected units are included in Appendix C. 

Table 5. REM/Rate Modeling Results

Unit Number Percent Savings Over User 

Defined Reference Home HERS ENERGY STAR v3 Tier II

Unit 2 30.7% 68 Yes

Unit 3 33.3% 66 Yes

Unit 8 43.5% 50 Yes

Unit 9 38.2% 55 Yes

All units qualify for Tier II (30% savings), but they do not qualify for Tier III incentives (45%). 

In order for each apartment to reach that savings level, significant upgrades to the proposed 

measures were required. A solar DHW system is an example of the type of measure required to 

meet Tier III; upgrades of this magnitude were not accounted for in the project budget. 

Window Performance Analysis

The existing windows at the building were vinyl double-glazed (clear) insert replacement 

windows (U ≈ 0.5); they were a circa 1980s replacement, and appeared to be in reasonable 

condition (Figure 20). The initial decision for the window retrofit was to retain these existing 

vinyl units, and add low-e storm windows to bring up the overall U-value of the assembly (U ≈ 

0.34). 

At that time, the energy analysis was performed to determine the tier levels the apartment units 

would be able to qualify for. All units were able to reach Tier II incentives with the addition of 

low-e storms. Construction details were drawn to show the removal of the existing windows, 
27 

installation of flashing at the wood-framed window openings, and reinstallation of the existing 

units. See Appendix B for the retrofit construction details, and Figure 21 for a test installation of 

these retrofit details.

Figure 20. Existing vinyl double-glazed (clear) insert replacement windows

Figure 21. Test retrofit installation of flashing at the wood framed window openings

Estimates for purchasing low-e storm windows were provided by Harvey Industries. The team 

asked the manufacturer to calculate the cost of new ENERGY STAR-qualified windows as well. 

The quote included pricing for 120 windows of various sizes. Table 6 lists cost for adding single 

glazed, hard coat low-e storms, and double-glazed, low-e, argon-filled vinyl windows (U = 0.30, 

SHGC = 0.30).
28 

Table 6. Window Cost Comparison

Manufacturer Low-E Storm 

Window

ENERGY STAR-Qualified 

Vinyl Window

Harvey Industries $18,768.62 $23,804.45

The cost difference between adding low-e storm windows and installing new ENERGY STARqualified units is approximately $5,000, or a 27% increase. The average cost for a low-e storm 

window is $156 and for a new double-glazed vinyl unit the cost is $198. 

However, due to the budget constraints for this extensive retrofit, the project team began 

considering only keeping the existing windows and omitting the low-e storm windows. Retaining 

the existing windows would impact the ability for each of the apartments to qualify for the Tier 

II; therefore, additional energy analysis was performed using REM/Rate software to compare 

three alternatives for the window retrofit:

• Retain the existing windows. 

• Add low-e storms (to improve the overall U-value of the existing windows). 

• Replace the existing units with new ENERGY STAR qualified windows. 

The results of the analysis are shown in Table 7. 
29 

Table 7. Window Performance Energy Analysis

Window 

Options % Savings Over User Defined Reference Home Tier Levels

Unit 1 Unit 2 Unit 3 Unit 4 Unit 5 Unit 6 Unit 7 Unit 8 Unit 9 Unit 10 Total 

Tier I

Total 

Tier II

Total 

Tier III

U = 0.49 

SGHC = 0.60 24.3% 22.7% 23.4% 27.5% 28.0% 25.5% 27.7% 38.2% 34.0% 33.9% 7 3 0 

U = 0.34 

SGHC = 0.48 31.1% 30.7% 33.2% 35.6% 36.9% 35.1% 35.6% 43.5% 39.3% 38.7% 0 10 0 

U = 0.30 

SGHC = 0.30 30.2% 30.1% 33.5% 36.2% 37.3% 35.6% 36.0% 43.0% 37.1% 37.5% 0 10 0 
30 

The analysis showed that either adding low-e storms or replacing the existing windows would 

qualify all 10 units for the Tier II (30%+) incentive. However, retaining the existing windows 

resulted in only three units meeting Tier II.

In October of 2012, the MVHfH board of directors met in order to determine the budget for the 

window retrofit. The members were presented with the information above, and based on the 

results of the analysis (as well as the window estimates), the board decided to approve the funds 

to replace the existing windows with ENERGY STAR-qualified vinyl units. 

The replacement of the existing windows with new construction vinyl units will be a much more 

straightforward process for the volunteers, compared to retrofit flashing of the existing window 

openings (Figure 21). The project team often works with volunteers who have little or no 

construction experience, and may be on site for a short amount of time; therefore, the team 

leaders have to train new volunteers on a regular basis. 

The new plan for the retrofit of the windows will involve the preparation of the existing window 

openings to receive new construction (flanged) windows, which are considered simpler for 

volunteer installation. Two considered options include removal of the existing wood frame in the 

window openings, followed by installation of new 2x pressure treated rough bucks, or the 

installation of new blocking on the existing wood frames. The rough opening would then be 

waterproofed, including the installation of a sill pan flashing draining to the exterior sill. The 

project team is currently trying to secure a donation of liquid-applied flashing, which would 

simplify the treatment of window rough opening by unskilled volunteers, and as a result, 

improve quality and accelerate the construction process.

Other Incentives

Habitat for Humanity is a nonprofit organization and is, therefore, allocated under a certain tax 

criterion. As a result, the project may not able to qualify for state and federal tax credits related 

to energy efficiency. However, there a number of state and federal tax credits that other projects 

may be eligible for. There are also local rebates and zero financing loans that can help offset or 

finance the cost of energy efficiency improvements (Mass Save 2012).

The project team sought other alternatives for financing the implementation of retrofit measures 

in the building. The MVHfH team applied for a $200,000 grant through the Federal Home Loan 

Bank of Boston to complete structural work, water main repairs, and other essential fixes related 

to the basic function of the building. The terms of the grant dictate that the project also applies 

for a matching loan from a partner bank. 
31 

5 Retrofit Air Barrier Strategies and Assemblies

The importance of air barriers and the reduction of uncontrolled air leakage has been well 

established (Wilson 1961; Straube and Burnett 2005; Lstiburek 2005a; ASHRAE 2009). 

Effective air barriers are an important component for good energy performance, good indoor air 

quality, and control of interstitial condensation. In addition, an effective air barrier between units 

of multifamily housing reduces transmission of sound, odors, and smoke, lowers fire spread risk, 

and helps control stack-driven airflows (Lstiburek 2005b). 

Therefore, BSC established targets for air barrier and compartmentalization performance on the 

MVHfH project, and developed multiple details for airtightness (interior-to-exterior) and 

compartmentalization (unit-to-unit) strategies. A full detail set is provided in Appendix B. These 

details had to be developed with the knowledge that they would be implemented by volunteer 

crews, who might be untrained or on the site for only a short duration (i.e., little chance for 

improvement over time). In addition, these air barrier and compartmentalization details had to be 

developed for the specifics of this project, which involves an interior insulation retrofit of a 

multifamily mass masonry building.

The planned research is intended to analyze the effectiveness of air barrier strategies 

implemented in this multifamily retrofit; however, no units have been completed to date, so 

effectiveness has not been measured. However, some information is available on the secondary 

question, of the difficulties in implementing these air barrier details.

Exterior Wall Air Barrier

The construction of the masonry walls at this project include both multiwythe solid brick walls, 

and exterior brick with a hollow clay block infill/backup wall, as shown in Figure 22. These 

photos show conditions after demolition of the interior furring, lath, and plaster. 

Figure 22. (L) Exterior wall conditions at solid brick; (R) hollow clay block infill conditions

Although these assemblies appear to be monolithic from the interior and exterior, there are a 

variety of interconnected air spaces, such as the incompletely filled collar joints between brick 

wythes (Figure 23, left). In addition, the hollow clay blocks provide a major interconnected 

airflow network laterally across the wall (Figure 23, right). 
32 

Figure 23. (L) Wall section at solid brick; (R) at hollow clay block infill conditions

Wilson (1961) documented that bare masonry is a source of air leakage, as shown in Table 8. 

The measured air leakage (3.1 in.2/100 ft2 surface area) is higher than the base leakage rate 

requirements in many energy efficiency programs (e.g., 2.5 in.2

/100 ft2 surface area). However, 

an air barrier (such as a three-coat plaster parge) renders the air leakage through the assembly 

negligible.

Table 8. Air Leakage through Masonry Materials 

(Wilson 1961)

Assembly Equivalent Orifice, Areas

(in.2)

13-in. Porous Brick Wall, No Plaster, 100 ft2 3.1

Wall as Above, 3-Coat Plaster, 100 ft2 0.054

Options for retrofitting an air barrier at a mass masonry wall include the application of a liquidapplied or membrane air barrier on the interior side, or the use of an insulation material that 

creates an air barrier. The selected retrofit strategy was to use multiple layers of rigid foam board 

insulation inboard of the masonry to provide both insulation and an air barrier. The use of rigid 

board foam as an interior retrofit of masonry walls has been covered by Straube et al. (2012), and 

Natarajan and Klocke (2011). Having an effective air barrier at this interior retrofit is critical for 

both energy performance, and for durability, to avoid wintertime air leakage condensation at the 

insulation-masonry interface (Straube et al. 2012). 

The retrofit assembly consists of three 2-in. layers of XPS rigid insulation (with staggered 

seams), adhered to the masonry and between layers with a single-component polyurethane 

adhesive. The outermost and innermost layers of rigid insulation have joints taped to create an air 

barrier. Wood 2 × 4 framing is installed inboard of these layers, with no insulation in the stud 

bay cavities, for interior finishes and to provide space for running services. 

The adhesive used for the rigid insulation was Dow Insta-Stik, which is currently in use in 

United States as a commercial roof adhesive (adheres compatible roof insulation boards to roof 

decks and substrates in new roof and roof replacement applications). The adhesive is formulated 
33 

to have a quick curing time (board can be held in place until adhesion occurs), and minimal 

expansion (does not push board off of wall), while providing some gap-filling properties. It is 

specified to work over a wide range of temperatures (33°–111°F or 0.5°–43°C). It is currently 

used in Europe to adhere plasterboard and rigid insulation to existing masonry assemblies (Dow 

Building Solutions 2007). 

The installation of the rigid foam board is shown in Figure 24, including the application of 

adhesive. The adhesive bead is applied in a manner that provides some degree of isolation and 

compartmentalization of the gap between the masonry and insulation, thus reducing the extent of 

convective looping. 

Figure 24. (L) Test installation of foam on masonry; (R) use of polyurethane adhesive

The completed insulation installation with taped seams is shown in Figure 25 (left). A smallscale mockup was built to provide volunteers with a visual example of the retrofit assembly 

geometries (Figure 25, right). 

Figure 25. (L) Multiple layers of insulation; (R) mockup for volunteer education
34 

The framing inboard of the insulation is shown in Figure 26 (left); note that the framing is 

installed only after complete installation of the rigid insulation. Therefore, access for taping 

seams of the air barrier layer is not hampered by the framing.

Although the layers of taped rigid foam provide an effective air barrier in the field of the wall, 

the penetrations through this layer are a potential failure point for air barrier continuity. For 

instance, at the windows (Figure 26, right), air barrier continuity needs to be achieved from the 

foam to the window unit. The air spaces between the layers of foam have the potential to form a 

three-dimensional network of airflow paths. 

Figure 26. (L) Framing installed inboard of insulation; (R) conditions at window opening

The solution detail uses two-component spray foam kits to “cap” the exposed foam edges, and 

connect them to the window rough opening, as shown in Figure 27. The window opening 

flashing materials (membrane or liquid-applied) are in turn connected to the window unit using 

low-expansion foam. 
35 

Figure 27. Window jamb retrofit detail, showing spray foam “fillet” for air barrier continuity

However, the precise window details are still in flux. For instance, Figure 27 shows the existing 

double-glazed vinyl-frame insert window, with an exterior low-e storm. Since drafting that 

detail, the plan has changed to retrofit new construction low-e double-glazed windows 

(ENERGY STAR-rated) into the openings. In addition, the Habitat for Humanity team has 

pushed to change to flanged windows, due to ease of installation by volunteers (as opposed to 

two-stage caulk joint required for insert window units, as shown in Figure 27). BSC plans to 

work with Habitat to develop further details, but will include the air barrier detail of a fillet of 

spray foam connecting the edges of the rigid insulation board to window rough opening. 

Other wall penetrations, such as the outside air supply/exhaust duct for the unit-by-unit HRVs, 

will be treated in a similar way, with a spray foam seal between the duct and the rigid foam 

board. 

Roof-to-wall connections and compartmentalization details (including wall-to-floor details) are 

covered in following sections. 

Roof and Roof-to-Wall Air Barrier

The existing roofs on this building included low-slope built-up roofs with aggregate (gravel) 

topping, and slate roofing on the sloping portions. There is a “lower” flat roof (ceiling of second 
36 

floor) with a parapet, and a smaller “upper” flat roof (ceiling of the third floor), as shown in 

Figure 28. 

Figure 28. (L) Lower roof, showing upper roof; (R) upper roof

All of these roofs were reported to be at end of service life, so a complete roof replacement was 

executed. Two critical aspects for the roof replacement were good air barrier continuity at the 

roof-to-wall interface, and an effective air barrier at the underside of the layers of rigid 

insulation. This latter requirement prevents interior air leakage into the “sandwich” of insulation 

and roof membrane layers, which could result in wintertime condensation and moisture buildup 

issues (see Lstiburek 2009, 2011). 

The assembly for the lower flat roof (which has a masonry parapet) is shown in Figure 29. It 

shows that the air barrier connection from the wall (rigid insulation) to the roof is made via 2 

lb/ft3 ccSPF, which “caps” the edge of the rigid insulation and connects it to the underside of the 

roof deck and the masonry parapet. 

On the top side, a layer of self-adhered membrane is installed under the layers of rigid insulation 

and wrapped up the parapet, to provide an air barrier at the underside of the “roof sandwich” 

discussed above. This air barrier is actually somewhat redundant, given the spray foam installed 

from the underside; however, it was selected due to some of the specifics of this project.
37 

Figure 29. Lower roof retrofit detail at parapet

During the installation of the lower roof, it was found that the air barrier layer was not being 

installed; instead, the rigid insulation was being installed directly on the roof board sheathing 

(Figure 30). The site supervisor was notified of this deficiency, and it was corrected over the 

weekend before completion of the roof membrane installation. 

Figure 30. Insulation of lower roof, showing lack of air barrier at board sheathing
38 

The completed lower roof is shown in Figure 31; the sloped portions of the roof were finished 

with asphalt shingles.

Figure 31. (L) Lower roof, showing upper roof; (R) upper roof

At the upper roof, instead of applying a layer of self-adhered membrane to the roof board 

sheathing as an air barrier, the existing built-up roof was left in place, patched, and used as the 

air barrier layer, as shown in Figure 32. ccSPF also provides air barrier continuity and insulation 

at the flat and sloping portions of the roof. The completed upper roof is shown in Figure 33. 

Figure 32. Upper roof retrofit detail at intersection with sloping roof
39 

Figure 33. (L) Upper roof typical conditions; (R) upper roof edge detail

One example of the air barrier connection between the above-grade wall and the sloping roof is 

shown in Figure 34: the wall rigid foam board was left clear of the roof, and the connection from 

the wall air barrier to the roof spray foam air barrier was made with ccSPF. The example shown 

in Figure 34 was done by the volunteer crew using a spray foam insulation kit; however, it could 

be done instead by the professional spray foam contractor when the field of the roof is done. 

Figure 34. (L) Rigid wall insulation left clear of roof; (R) infill with spray foam kit

Below-Grade Air Barrier

Although the below-grade building enclosure is not commonly thought of as a major air leakage 

location, air barrier continuity is critical at this portion of the building. First, diffuse air leakage 

occurs through the soil, which is commonly air permeable (see Ueno and Lstiburek 2012). 

Second, the surrounding earth can be a source of air-transported contaminants such as moisture 

(water vapor), soil gases, and radon, which have negative effects on health, safety, and 

durability. Wintertime stack effect will tend to pull soil gases from the earth into the building 

through any air barrier imperfection.
40 

The ideal new construction slab design is shown in Figure 35, which is taken from Lstiburek 

(2007). It consists of (from bottom to top) some type of granular fill/gravel to create a capillary 

break from the earth below, a layer of moisture-insensitive insulation, an air and vapor 

impermeable membrane (such as polyethylene), and the concrete slab, cast directly onto the 

membrane. 

Figure 35. “Perfect slab,” showing polyethylene and insulation control layers 

(Lstiburek/BSC 2007)

The functions of various layers as air barriers and vapor barriers are discussed by Lstiburek 

(2008). The concrete slab functions as the air barrier (and needs to be continuous), while the 

polyethylene functions as the vapor barrier, and can have discontinuities, holes, or tears without 

substantial loss of performance.

The retrofit design went through several iterations; there are existing concrete slab floors 

throughout the basement, but at different elevations. One proposed retrofit was to build a rigid 

insulation and wood sheathing-based “floating floor” on top of the existing slabs. However, this 

places an assembly with poor flood recoverability in a basement, which is a risky decision. 

Therefore, the team decided to build a new construction basement slab over the existing slab; 

existing head height was sufficient to allow a greater assembly thickness. The retrofit assembly 

was, from bottom to top: 

• Existing concrete slab (no vapor control beneath) 

• Compacted earth fill

• Sand topping layer, screeded level with the highest slab 

• Extruded polystyrene (2 in. thick) 

• 6 mil polyethylene vapor barrier

• Cast concrete slab, 3-in. thick nominal.

In the area with the highest slab, the compacted earth fill and sand were omitted, to create a level 

substrate for the XPS insulation. 

As previously described by Lstiburek (2008), the air barrier is primarily the concrete slab. But to 

some degree, the polyethylene adhered to the underside of the slab effectively acts in a 

composite or secondary role, potentially bridging gaps and cracks at the slab. The details shown 

below use the polyethylene to “pass” the air barrier from the slab to adjacent components, such 

as ccSPF applied to the below-grade walls, as shown in Figure 36. 
41 

That detail shows the retrofit slab layers described above. At the slab edge, the polyethylene 

wraps up the edge of the slab, and an effective air barrier connection is made by the ccSPF, 

which is directly applied to the rubble stone foundation wall (see Ueno and Lstiburek 2012). 

The detail also shows the installation of a subslab radon collection system. No testing was done 

to indicate that radon is a known problem; however, the team decided to install the system. This 

is due to the fact that installing the subslab components is a simple change prior to casting of the 

slab, but prohibitively expensive as a retrofit. The system is currently planned as a passive stack 

vented through the roof, but a powered radon mitigation fan can be retrofitted if high radon 

levels are found in service.

Figure 36. Typical basement slab and bottom of wall detail

The original plan was to use corrugated perforated drainage pipe for radon collection (Figure 37, 

left). However, accommodating this pipe in the earth fill/sand layer would result in a substantial 

loss in head height, and would require additional fill. Therefore, the team decided on a lowprofile radon vent mat, which consists of a plastic air gap membrane mat wrapped in a geotextile 

sleeve (see Figure 37, right and Figure 38, left). The radon vent is installed around the perimeter 

of the slab (see Figure 38, right), and connected to through-slab pipe stubs. 
42 

Figure 37. (L) 4 in. nominal corrugated drainage pipe; (R) low-profile radon vent mat

Figure 38. (L) Dimpled core of radon vent mat; (R) radon vent map installed under XPS

The completed slab insulation work (prior to installation of polyethylene) is shown in Figure 39; 

the slab edge insulation is temporarily held in place by one-component polyurethane adhesive 

(Figure 39, right).
43 

Figure 39. (L) Installed subslab insulation at basement; (R) detail of slab edge insulation

The condition of the edge detail after the casting of the slab is shown in Figure 40 (left); the 

polyethylene “flap” is available for an air barrier connection to the spray foam used at the bottom 

of the wall (at the rubble stone section at the base of the wall). Interior framing installation is 

shown in Figure 40 (left).

Figure 40. (L) Edge detail after casting of slab; (R) installation of interior framing

Compartmentalization Details

An effective air barrier between units of multifamily housing reduces transmission of sound, 

odors, and smoke, lowers fire spread risk, and helps control stack-driven airflows (Lstiburek 

2005b). However, creating effective compartmentalization between units—particularly in light 

frame construction—is often difficult. The wall, roof, and floor assemblies in light frame 

buildings are not monolithic assemblies: instead, they are hollow and contain multiple layers, air 

gaps, and void spaces which can be interconnected by many unintentional paths. These complex 

three-dimensional airflow networks can defeat efforts at compartmentalization, as shown in 

Figure 41 (Lstiburek 2000). 
44 

Figure 41. (L) Three-dimensional multilayer multicell analogue; 

(R) air pressure fields connecting noncontiguous spaces) 

(Lstiburek/BSC 2000)

Therefore, details were drawn to create effective compartmentalization between units; they also 

had to account for constructability (including sequencing), and in particular, construction by 

largely untrained volunteers. In addition, many of these details also need to meet fire resistance 

ratings (2-h unit-to-unit; 1-h unit-to-hall), which adds further complications. 

One unit-to-unit detail is the floor/ceiling assembly’s intersection with the exterior wall; the 

floor/ceiling is a rated assembly, and the detail must provide air barrier continuity (unit-to-unit 

and unit-to-exterior). The typical detail with the floor joists perpendicular to the exterior wall is 

shown in Figure 42. 

The interior-to-exterior air barrier is “passed” from the layers of rigid foam (XPS), through 

ccSPF insulation and fire resistance elements, to the rigid foam on the floor above. 

The fire resistance requirements mean that the floor-to-ceiling assembly must be extended to the 

exterior wall (gypsum board and floor sheathing). Due to construction sequencing, a “strip” of 

each must be placed at the perimeter during wall construction, before the field of the ceiling is 

built. The gypsum board detail is shown in Figure 43. Note that instead of the “step back” detail 

and spray foam, the interior layer of rigid insulation is caulked to the face of the strip of fire 

separation gypsum board (Figure 43, left). Note that Figure 43 (left) shows four layers of foam; 

the additional layer is a strip of foam filling the web of the steel lintel over the window.
45 

Figure 42. Unit-to-unit floor/ceiling assembly at exterior wall; joists perpendicular to wall

BSC recommended non paper-faced gypsum board to the team for the fire separation “strip,” as 

it is in direct contact with the masonry. However, the team decided to use a paper-faced mold 

resistant gypsum board instead. This strip will in turn be tied to the ceiling gypsum board, which 

provides unit-to-unit separation. 

Figure 43. (L) Floor/ceiling fire separation gypsum board; (R) conditions after interior framing
46 

The insulation detail at the joist ends is shown in Figure 44; instead of using spray foam to 

insulate and air seal (as per Figure 42), scraps of rigid foam insulation were used, adhered with 

polyurethane adhesive. This was due to the fact that given volunteer labor, this is a less costly 

approach than spray foam, and uses the available scrap.

Figure 44. (L) Rim joist foam blocks; (R) close-up showing clamping jig

Note that there is a generous space at the perimeter of each block, which allows effective air 

sealing with a spray foam kit. 

The floor detail is shown in Figure 45, showing the strip of floor sheathing at the perimeter, and 

the caulk seal between the subfloor and the rigid board insulation. 

Figure 45. (L) Floor edge detail, showing added floor sheathing; 

(R) air seal between foam and floor

Given the complexity of this detail, a step-by-step construction sequence was provided to the 

team.
47 

The remaining details cover unit-to-unit compartmentalization at interior framed walls and 

floors. Given that interior wall framing has only recently started, these details have not been 

built, much less tested for air leakage performance.

In general, the compartmentalization details use the interior gypsum as the air barrier, except at 

the exterior walls, where the rigid insulation is the air barrier. The details also note that since the 

gypsum board is the air barrier, all penetrations must be airtight, such as electrical boxes, and 

mechanical or plumbing penetrations. Through-demising-wall penetrations must be sealed to the 

gypsum board on both sides of the assembly. 

The detail for a demising wall intersecting the exterior wall is shown in Figure 46: it is 

conceptually similar to the floor-to-ceiling intersection detail shown in Figure 42, with the 

“strip” of mold-resistant gypsum board where it is hidden within the exterior wall assembly, to 

provide continuous fire resistance to the masonry wall. Again, spray foam is used to connect the 

exterior wall air barrier (XPS) to the demising wall air barrier (gypsum board), and “cap” the 

edges. 

Figure 46. Rated partition intersection with exterior wall
48 

Nailers are necessary for attaching the gypsum board perpendicular to the demising wall. In 

addition, the end stud of the demising wall is held off of the exterior wall (with a 2-in. piece of 

mineral fiber insulation), to avoid contact between vulnerable wood framing and the cold 

exterior wall.

At the floor-to-ceiling assembly, the air barrier is the ceiling gypsum board, given that the floor 

sheathing has already been installed, or existing flooring (tongue and groove wood) is remaining 

in place, or both. Neither of these flooring options can readily be made airtight. Again, 

penetrations such as light fixtures must be sealed at the ceiling gypsum board. Any interior 

soffits (such as those being used to conceal the HRV ductwork) must be built with the gypsum 

board (or other air barrier material) continuous behind the soffit (see Figure 48, left).

In addition, interior partitions penetrate through this ceiling gypsum board, interrupting the 

continuity of the layer. Therefore, the air barrier must be “passed” through the top plate of the 

non-rated walls, as shown in Figure 47. The ceiling gypsum board is connected to the nonrated 

partition gypsum board with a typical taped corner joint, the wall gypsum board in turn connects 

to the top plate with a gasket. 

Any penetrations through the top plate for electrical or plumbing services must be air sealed at 

the top plate, similar to an interior wall under a vented attic (see Figure 48, right).

Figure 47. Within-unit (nonrated) partition wall intersection with ceiling
49 

Figure 48. (L) Soffit with air barrier continuous above; (R) air sealing of top plate penetrations

Demising walls between units have fire resistance rating and compartmentalization (unit-to-unit) 

requirements. Therefore, the fire rated partition must extend up into the floor cavity, as shown in 

Figure 49. 

The rated wall gypsum board is sealed to the floor sheathing (at bottom and top) with fire rated 

sealant or expanding board: this is a somewhat “weak” air barrier connection, given that the 

gypsum board air barrier is “passed” through a potentially air permeable material (floor board 

sheathing plus existing finish floor). However, there are no other reasonable options, given the 

existing conditions. 

Figure 49. Unit-to-unit (rated) floor-to-ceiling assembly at demising wall; joists parallel to wall
50 

At the condition where the demising wall is perpendicular to the joists (rather than parallel, as 

per Figure 49), the gypsum board is notched around the joists and sealed with fire-rated 

expanding foam. 

The Habitat team developed these details further on site. For instance, the notched gypsum board 

at the demising wall above the finish ceiling was demonstrated by a senior volunteer in Figure 50

(left); sufficient space was left at the notches to air seal with fire-rated foam at the openings. At 

unit interior partition walls, the Habitat team found that rather than “passing” the air barrier 

through the top plate with air sealing details, it was simpler to run the ceiling gypsum board 

continuously and frame the partition below this gypsum board layer (see Figure 50 right). These 

images also show the use of fiberglass batt and resilient channel for acoustic separation.

Figure 50. (L) Notched gypsum board at demising wall; (R) ceiling gypsum board continuous over 

unit interior partition walls

To help the team to put these details in context, a table was made showing the relevant interface 

detail between the air barrier assemblies (wall, ceiling, and floor), as shown in Table 9. 

Table 9. Air Barrier Connections Between Air Barrier Element Detail Listing

Exterior Wall Demising Wall Ceiling Floor

Exterior Wall – – – –

Demising Wall W3 – – –

Ceiling W1 W4, W5 – –

Floor W1 W4 n/a –

In addition, the following outline-form narrative was included with the air barrier details, to give 

the team a greater understanding of the compartmentalization strategies being implemented.

• Goals and principles of air barriers and compartmentalization 

o Each unit should be airtight as possible to the outside 

o Each unit should be isolated/airtight from another (“compartmentalization”) 

o Each unit should be isolated/airtight from the corridor (“compartmentalization”) 
51 

o We are designating an airtight plane on “all six sides of the cube” (each unit) 

 Each plane needs to be made airtight as possible: it must be made of an 

airtight material, and penetrations through the air barrier layer must be 

sealed to the air barrier 

 Each plane needs to be connected to the adjacent plane in an airtight manner 

• Exterior wall air barrier (inside-to-outside) 

o The XPS (extruded polystyrene) rigid foam insulation forms the air barrier at the 

exterior walls; the seams are taped at the outermost and innermost layers.

o Closed-cell spray foam is used to connect the XPS at difficult transitions (to window 

opening, portions of uneven surface brick, and the joist/floor areas (see Detail W1).

o Windows and doors must be connected to the air barrier layer (see Details WS, 

WH, WJ)

• Demising wall air barrier (unit-to-unit and unit-to-corridor) 

o The surface of the gypsum board is the air barrier layer, on each side of the 

demising wall 

o All penetrations through the gypsum board must be made airtight: 

 Electrical boxes should be airtight boxes, or alternately, caulked/sealed boxes

 All mechanical and plumbing penetrations must be sealed to the gypsum 

board, where they penetrate through, on each side of the drywall 

o Connections to the exterior wall as per Detail W3 (spray foam connection to XPS) 

o Connections to the floor and ceiling air barrier to be done with caulk, sealant, or 

gaskets (Detail W4, W5)

• Ceiling (gypsum board side) air barrier 

o Where the ceiling gypsum board is interrupted by partition wall framing, the air 

barrier must be “passed” through the framing (Detail W6) 

o Any soffits must be built with the gypsum (or other air barrier) continuous behind 

the soffit (Detail A1)

o All penetrations through the gypsum board must be made airtight: 

 Electrical boxes should be airtight boxes, or alternately, caulked/sealed boxes 

(Detail A3, A4) 

 All mechanical and plumbing penetrations must be sealed to the gypsum 

board, where they penetrate through, on each side of the drywall (Detail A3) 

 Attic hatch must be made airtight (Detail A2) 

• Floor (flooring side) air barrier 

All penetrations through the subfloor must be sealed (e.g., plumbing and wiring penetrations) 

(Detail A3)
52 

6 Retrofit Mechanical Design

Previous research has indicated that unit compartmentalization combined with individual HVAC 

systems result in more efficient operation and improved individual unit control (Lstiburek 

2005b). Hydronic heating systems can be designed to provide good efficiency in low load 

residences (Siegenthaler 2011), especially by the use of low temperature distribution. Monitored 

data from field installations have indicated that combination space heating and DHW systems 

can meet the smaller demands of low-load homes with high efficiencies (Rudd 2010). However, 

although they can be high performance, low-cost systems, some in industry posit that using 

DHW equipment for space heating applications results in excess complexity (Rudd et al. 2011). 

Data from both monitored field installations and computerized analysis indicate that while high 

efficiencies can be achieved with condensing boilers, a better understanding of the actual versus 

predicted performance is needed (Zoeller 2011). 

Use of individual unit space heating and DHW systems greatly reduces the distribution losses 

associated with these systems, at a comparable net cost to centralized systems. The losses 

associated with centralized DHW system distribution and recirculation have been measured at 

roughly one third of the total energy use for DHW (CEC 2008; Zobrist 2012). The use of 

individual unit HRV systems greatly improves compartmentalization, and based on preliminary 

analysis, provides substantial first cost savings relative to a large centralized HRV system. The 

smaller, more compact, distribution systems will also result in fewer intrusions into the living 

space (e.g., dropped ceilings and vertical chases) for placing these larger systems. Use of 

individual tankless water heaters and HRV units in each condominium will also provide the 

homeowners with the ability to control the settings according to their particular lifestyle and 

desired comfort levels. The tradeoffs associated with this approach, however, are the challenges 

of locating individual tankless water heaters and HRVs in each apartment, and the placement of 

the entire distribution system within the fire-rated assembly, to avoid the need for costly 

mechanical fire protection equipment (fire dampers, rated shafts, etc.).

Therefore, BSC developed a mechanical design with individual mechanical systems for each 

apartment unit, and for the common areas of the MVHfH multifamily building. Designs were 

developed for installing small HVAC systems in each apartment, including full mechanical plans 

with complete specifications on selected equipment. One aspect of the ventilation design (the 

kitchen exhaust) is to be a centralized system as incompatibilities in the floor plans did not allow 

individual unit kitchen exhaust ducts to be effectively placed. 

This research project seeks to address two questions related to the HVAC design in this 

multifamily building:

• What are the performance and cost impacts of implementing a compartmentalized 

ventilation strategy with individual apartment HRV systems versus a traditional large 

single central HRV system?

• What are the performance and cost impacts of using individual unit combination space 

heating/hot water units, including the effects of distribution piping and installation 

specifics?
53 

However, no mechanical systems have been installed to date, nor have any quotes been received 

for the design. Therefore, the cost impacts cannot be determined at this point, but details on the 

current HVAC design are available. The designs are complete and have been submitted to the 

MVHfH project team.

Hydronic Heating 

Hydronic heating constitutes the predominant heating system in the Northeast, with either No. 2 

fuel oil or natural gas as the fossil fuel energy source (EIA 2009). The existing heating system at 

the convent was a single large centralized oil steam boiler with cast iron radiators for 

distribution. Hydronic installations are usually preferred to forced hot air systems in retrofits in 

this region due to easier installation in an existing building. Another reason is that centralized air 

conditioning historically was not often installed in residential buildings in the region, which is a 

Cold Climate and an International Energy Conservation Code Climate Zone 5 (ICC 2009c). 

As part of Habitat for Humanity’s policy in this region, centralized air conditioning was not 

considered for this project. Therefore, hydronic heating with baseboard distribution was 

determined to be the most cost effective design for this building. Natural gas is available onsite 

and will be used for appliances; therefore, oil was not considered as the fuel source for the 

heating system.

A local engineer provided an initial mechanical design that included individual gas hot water 

boilers for each apartment and the common areas. BSC reviewed the design with a local 

plumbing contractor who is providing the plumbing design for the building, and further 

developed the design. 

The gas water boiler that was selected was a high efficiency, sealed combustion, condensing 

combination space/DHW heater from Navien. The original selected convectors were standard 

finned tube radiation baseboard. 
54 

Figure 51 shows the original heating system schematic.

Figure 51. Original apartment hydronic schematic

This design did have positive traits, but BSC identified elements that required additional 

development. The discussion below outlines BSC’s initial evaluation of the design and 

recommended improvements. Some of the improvements were recommended with the 

knowledge that Watts Water Technologies will be donating any products in its line to Habitat for 

Humanity for the convent retrofit effort.

Positive

Combination heat/water boiler—A strong attribute for this boiler is that it has separate outlet 

taps for both space heating and DHW. Thus, a single unit can be utilized to provide heat and hot 

water for the apartments without the complexities associated with converting a standard one tap 

boiler to serve as a combination heat and hot water unit. Those issues would include using a heat 

exchanger for the nonpotable loop, or using potable water in the heating distribution system. 

While working on system design, BSC determined that the smaller model, the Navien CH-180, is 

better matched to the loads of these small apartments. 

Buffer tank—The original design included an optional 80-gallon buffer tank for future 

installation if necessary. The purpose of this tank is to prevent severe short cycling of the boiler 

during part-load operation. It is suspected that rapid short cycling with boilers in very low-load 

applications can dramatically reduce the lifetime of the boiler components and can increase 

operating costs (McKeegan and Patterson-Kelley 2005). BSC remains receptive to this concept; 

however, the buffer tank was not selected for this project because of cost concerns—not only due 

to mechanical equipment, but because of the additional structural reinforcing required at each 

mechanical closet. The boiler manufacturer maintains that the boiler is designed to operate in 

part load conditions and did not recommend a buffer tank for this application. 
55 

Negative

Standard baseboard—Standard finned tube radiators must operate at high temperatures to heat 

a space. The system was designed for a baseboard supply water temperature of 160°F, with the 

return water temperature in the range of 149°–153°F. At these return water temperatures, it is 

likely that condensation will not occur at the water heater, thus reducing the operating efficiency 

of the boiler to that of a standard noncondensing unit (blue lines in Error! Reference source not 

found.Figure 52). 

Figure 52: Thermal efficiency plot as a function of inlet water temperature 

The reason why standard baseboard typically operates at a high water temperature is twofold. 

First, standard baseboard has a low Btu output per linear foot (Btu/ft), which is intrinsic to the 

one pipe design. Therefore, high supply temperatures are required to increase the Btu/ft to such 

that reasonable length of baseboard can fit in a room. Second, standard baseboard is typically not 

rated for supply temperatures below 120°F, which is the around the highest recommended water 

temperature to ensure that the return temperature is low enough for condensation at the boiler. In 

the cases where standard baseboard is rated below 120°F, its heat output drops precipitously, 

thus requiring even more of a prohibitive length of baseboard to adequately heat a space. 

Therefore, BSC recommended a high-output, two-pipe baseboard called the Heating Edge 2 from 

Smith Environmental (Figure 53). This baseboard is rated to supply the equivalent Btu output at 

120°F as standard baseboard operating at 180°F. This increased capacity per linear foot allowed 

for the adequate placement of baseboard in every room in the building without having to resort to 

other terminations such as kickspace heaters and convectors. The local plumbing contractor with 
56 

whom BSC consulted on the hydronic design has installed this baseboard in previous homes and 

noted that the increased gauge of the cover sheet metal material greatly improved the durability 

of the product relative to standard baseboard. This led to a marked decrease in callbacks to repair 

damaged baseboard. As a note, fan-assisted panel radiators were briefly considered, but were 

rejected for cost reasons.

Figure 53. Smith Environmental HE2 high-capacity hybrid element

The two-pipe baseboard can be installed in a number of configurations, such that supply water 

can flow through both pipes in parallel or can circulate through both pipes. BSC specified the 

parallel piping configuration for this design, as it will result in the highest heat output (385 

Btu/h/ft at an average water temperature of 120°F).

Series distribution—The original design (Figure 51) included a primary-secondary loop system 

and specified the secondary loop with the terminations (baseboard radiation) piped in a series 

configuration. BSC upgraded to a parallel distribution design, with homeruns from each 

termination connected to a stainless steel manifold (Watts Flowmeter Manifold; Figure 54). Most 

of these upgrades will be donated by Watts Water Technologies. A benefit to parallel distribution 

is the potential for individual radiator control via thermostatic radiator valves. In addition, a 

parallel design significantly reduces flow resistance (and thus pumping energy). While at this 

point in the design it appears to be too costly to integrate thermostat controls at each termination, 

adjustments can still be made at the manifold during commissioning, or an enthusiastic 

homeowner may regulate the flow during occupancy. 
57 

Figure 54. Watts manifold with flow meters and balancing valves at each tap

Unnecessary plumbing devices—A number of plumbing devices in the original schematic were 

deemed unnecessary for this residential design. One was a bypass on the cold water line around 

the pressure release valve that was removed. There were also multiple balancing valves 

specified, one on the primary loop and one on the secondary loop. The balancing valve on the 

primary loop was deemed unnecessary. The balancing valve on the secondary loop was also 

removed as the specified stainless steel manifold has balancing valves at each of the homerun 

taps.

Additional Design Considerations

Variable-speed pumps—Variable-speed circulators have a number of advantages compared to 

standard pumps. These “smart” pumps include microprocessor-based variable-speed controls that 

will adjust flow with an electronically commutated motor to match the demand. This can be 

especially beneficial when installed in systems with thermostatic control at the terminations. 

Despite the fact that thermostatic control may not be installed at this building, BSC still decided 

to specify a variable-speed pump on the secondary loop of each system. They are also inherently 

more energy efficient and produce less noise than standard pumps. The specified pump, the 

Grundfos ALPHA 2, is expected to operate at less than 30 W under design conditions (Figure 

55).
58 

Figure 55. Grundfos ALPHA variable-speed pump

Updated Hydronic Schematic

BSC developed an updated schematic that represents many of the aforementioned improvements 

to the hydronic design (Figure 56). Appendix D provides the full set of mechanical plans, 

including the current hydronic design. 

Figure 56. Updated apartment hydronic schematic
59 

Cost Comparison

Table 10 and Table 11 compare the estimated costs of both the original and currently proposed 

hydronic heating designs. Product costs were established through retailers, while labor was 

estimated through discussions with the local plumber whom BSC has been working with. 

Table 10. Original Hydronic Design Cost (Whole Building)

Description Model # Cost/Unit Subtotal

Apartment Boiler Navien CH-240 11 $2,200 $24,200

System Pump Taco Model 009 F5 14 $200 $2,800

Standard Baseboard Beacon Morris Type SF-A 514 lf $11 $5,654

Piping PEX and associated devices $30,000

Labor $50,000

Total Cost $112,654

Table 11. BSC Current Hydronic Design Cost (Whole Building)

Description Model # Cost/Unit Subtotal

Apartment Boiler Navien CH-180 11 $1,900 $20,900

System Pump Grundfos ALPHA 14 $300 $4,200

High Output 

Baseboard Heating Edge 2 363 lf $30 $7,122 

Piping PEX and associated devices $30,000

Labor $50,000

Total Cost $112,222

The current individualized design saves only a nominal amount in terms of installed cost ($430); 

however, the current system is expected to save around $400/yr in heating and DHW costs for 

the entire building. This cost savings is attributed mainly to the increase in boiler efficiency, as 

the proposed design will allow for the boiler to operate in condensing mode compared to the 

initial design. BEopt is unable to capture savings due to other design improvements (i.e., 

variable-speed pumps or distribution losses). 

Peak Load Analysis

A full room-by-room Manual J8 (ACCA 2011) load calculation was performed on each of the 

apartments and the common areas. The computerized simulation included all of the enclosure 

improvements, such as the added insulation and reduced infiltration rate. The linear length of 

HE2 baseboard in each room is sized according to the peak heating load. 

Dilution Ventilation 

As buildings become more airtight, mechanical ventilation is being implemented around the 

country as a method of maintaining healthy indoor air quality in homes. Building codes, such as 

the 2012 International Residential Code, are now requiring controlled mechanical ventilation for 

homes that achieve airtightness levels below 5 ACH 50 (ICC 2009b). 

The primary purpose of mechanical ventilation is to exhaust stale air and to introduce less 

polluted outside air. Daily exposure to pollutants is very common in residential buildings, such 
60 

as excessive moisture, body odors, cooking emissions, volatile organic compound emissions, 

products of combustion, radon gas, pesticides, dust particles, viruses, and bacteria. Managing 

these pollutants improves the health and comfort of the occupants and the durability of the 

building (Rudd 2006). A mechanical ventilation design in a cold climate such as New England 

with excellent performance is continuously operated and balanced (i.e., a simultaneous 

combination of supply and exhaust) system. A balanced ventilation system will not affect the 

pressure of the interior space relative to the outdoors, thus preventing unintended airflow 

between units or outdoors. The simplest way to install a balanced ventilation system is to use 

small packaged ventilators such as HRVs. BSC recommends that the amount of outside air 

introduced to the space be consistent with the rate stipulated by the ASHRAE Standard 62.2: 

Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings (ASHRAE 

2010). The ASHRAE Standard 62.2 ventilation rates for these apartment units are in the range of 

32–42 CFM. 

Original Design

The engineer who provided the original hydronic heating design also submitted a ventilation 

design. This ventilation system consists of a single large HRV located in a mechanical room in 

the basement with a centralized duct system providing supply air to the main living space and 

exhausting stale air from the single bathroom in each apartment. 

The existing design was deemed to be far too costly to install and operate for the following 

reasons:

• The large central HRV was oversized and specified flows to the apartments were much 

higher than the ASHRAE Standard 62.2 rate (140 CFM versus 32–42 CFM). Not only is 

there an increased cost associated with the oversized HRV, but the overventilation of the 

apartments will negatively impact energy performance and will result in increased 

heating costs.

• An extensive centralized system of ductwork was specified, requiring a significant 

amount of duct material. Also worth noting is that the large size of the ductwork requires 

a heavier gauge sheet metal, thus resulting in higher material costs.

• The centralized ductwork would require a significant amount of dropped ceilings in the 

building, increasing cost and negatively affecting the aesthetic of the living spaces. 

• A series of smoke and fire dampers were specified to maintain the fire rated assembly 

between the apartment units, along with a controls sequence for operating the dampers in 

case of fire. 

• The shared duct system compromises the continuity of the air barrier between the 

apartments, thus increasing the risk of uncontrolled air leakage between the spaces 

(compromising compartmentalization). 

• Lack of individual ventilation control in the apartments, particularly in the bathrooms, as 

there is no option for intermittently increasing the exhaust flow if desired for odor and 

moisture removal.

• A series of duct chases are required for the centralized duct system to access all 

apartments.
61 

Figure 57 shows an example of the original ventilation design in one of the units. The extensive 

ductwork and associated fire and smoke dampers result in a complex and costly design.

Figure 57. Existing ventilation design at Unit 4

Another problem with the design is that supply flows were intentionally higher than exhaust 

flows, to pressurize the units, under a mistaken belief that this would prevent occupant draft 

complaints. Intentional pressurization of the units is likely to exacerbate air leakage 

condensation, resulting in durability issues.

BSC concluded that the design was not appropriate for a low-rise, energy-efficient residential 

building, and in keeping with the concept of compartmentalization (i.e., small individual 

mechanical systems), performed a full redesign of the ventilation system.

See Appendix D for the complete set of mechanical plans including the ventilation design. 

Current Ventilation Design—Building Science Corporation

The current ventilation strategy proposed by BSC is to specify small HRVs in each apartment, 

with a small duct system for distribution. An additional HRV will ventilate the common spaces 

in the building. This is known as a balanced multipoint HRV system, see Figure 58. 
62 

Figure 58. Ventilation strategy schematic

An HRV will be located in a mechanical closet in each apartment and in the common areas. A 

small duct system will provide ventilation to the bedrooms and will draw stale air from the 

bathrooms. Locating the HRV exhaust in the bathroom precludes the need for a separate bath 

fan, the ducting of which would have been complicated to route to the outside and also would 

have required an additional penetration through the apartment air barrier. When configuring a 

recovery ventilator to exhaust air from baths, it is recommended to specify an HRV, not an 

energy recovery ventilator. There are practitioners in the industry who recommend energy 

recovery ventilators for exhausting bathroom air, with the expectation (in a cold climate) that the 

moisture will be redistributed throughout the house and can increase the relative humidity in the 

living space during a cold and dry winter. However, BSC does not recommend this strategy in 

small airtight residences (especially with high continuous occupancy) in cold climates. Elevated 

moisture levels in the living space during the winter can increase the potential for condensation 

on any cold surfaces (e.g., window frames). 

Each apartment has one bathroom, making the HRV exhaust ducting simple. Nine out of the 10 

apartments have three bedrooms, with the tenth unit having two bedrooms. An HRV supply will 

be located in each of the bedrooms. The registers will be positioned to not supply air directly 

onto the beds in order to avoid potential comfort complaints. 

The specified HRV for the apartments is the Flex 100H from Fantech. The common areas will be 

ventilated with the VHR 2004 from Fantech. 

Figure 59 shows the intended installation setup, high on the mechanical closet wall with sheet 

metal runouts. 
63 

Figure 59. Proposed HRV installation example

The Fantech Flex 100H HRV was selected as the HRV for the apartments as it has a number of 

positive characteristics:

• Compact in size and is small enough to operate continuously, in low speed, at the 

recommended ASHRAE Standard 62.2 ventilation rate (32–42 CFM in the apartments).

• Recirculation defrost, which warms the core by circulating interior air, rather than the 

traditional mode of defrost that exhausts interior air to the outside. 

• Boost function—a push-button timer can be used to intermittently increase airflow. This 

will be installed in the bathroom to allow the homeowner to increase airflow when 

needed for odor or moisture removal. The increased airflow will be at least 50 CFM per 

the intermittent point source exhaust specification in ASHRAE 62.2 (ASHRAE 2010). 

• A balancing damper and airflow measurement ports are integrated with the HRV. 

The compartmentalization strategy of utilizing separate HRVs in each apartment results in a 

much smaller, more compact distribution system. Only 5-in. round sheet metal ducts are required 

for the distribution system. The ductwork is no longer interconnected between the apartments 

and common areas; therefore, fire and smoke dampers are not required. Figure 60 shows an 

example of the current duct layout for an apartment unit. The hatched sections indicate dropped 

ceilings. Where possible, the ducts will be located within the floor joist cavities to limit the area 

of dropped ceilings; however the floor joists are outside the fire-rated assembly for the 
64 

apartment. Therefore, any duct in the floor joists will need to be enclosed in a 1-h rated duct 

wrap to maintain the integrity of the fire-rated assembly. 

Figure 60. Example of current HRV duct layout

The exterior ducts of the HRV for the common areas and most of the apartments will be routed 

directly through an exterior wall (as opposed to a roof connection). Drilling holes in the existing 

mass masonry wall is cumbersome; therefore, BSC is specifying a dual exterior hood (e.g., the 

Tandem Transition from Venmar) for the HRV supply/exhaust termination. This exterior hood 

couples the two outside HRV ducts into a single termination, thus only a single 6-in. hole is 

required (Figure 61).

Figure 61. Dual exterior hood 

The project team has expressed a preference for limiting the number of penetrations through the 

mass masonry wall where possible. Therefore, the three apartments on the top floor will have the 

HRV outside air ducts routed through the roof with standard roof caps as the duct terminations. 

As a note, there is an unvented attic space at the roof that will allow the full ducting of the HRV 

distribution in the attic space for these three units. The ducts will be enclosed in a 1-h fire-rated 

duct wrap, but no dropped ceilings will be necessary for the three apartments.
65 

Cost Comparison

Table 12 and Table 13 below compare the estimated costs of both the existing and current HRV 

designs. Product costs were established through retailers, while labor was calculated per rates 

stipulated by the RSMeans (Reed 2012) costing source. 

Table 12. Original HRV Design Cost (Centralized System)

Description Model # Cost/Unit Subtotal

HRV Renewaire HE3XINH 1 $7,000 $7,000

Electric Duct Heater Indeeco Model QUA 1 $2,500 $2,500

Fire/Smoke Damper Ruskin Model FSD37 16 $400 $6,400

Smoke Damper Ruskin Model SD37 5 $400 $2,000

Fire Damper Ruskin Model IBD20 12 $80 $960

Control Damper Ruskin Model CD35 22 $86 $1,892

Ductwork Galvanized Steel 18,212 sf $0.64 $11,601

Labor $82,563

Total Cost $114,916

Table 13. BSC Current HRV Design Cost (Individualized Systems)

Description Model # Cost/Unit Subtotal

Apartment HRV Fantech Flex 100H 10 $525 $5,250

Common Area HRV Fantech VHR 2004 1 $743 $743

Exterior 

Termination Venmar Tandem Transition 10 $125 $1,250 

Main Control Fantech EDF1 Triple 

Function Wall Control 10 $30 $300 

Bath Control Fantech RTS3 Pushbutton 

Timer 10 $25 $250 

Ductwork Galvanized Steel 13,352 sf $0.64 $8,505

Labor $63,066

Total Cost $79,364

The current individualized design saves an estimated $36,000 compared to the original 

centralized design. These calculations do not include the costs of the fire-rated shafts (for the 

original design) or the 1-h rated duct wrap (for the current design, at incidental penetrations of 

the rated assemblies. However, it is likely that the latter is a lower overall cost. It is also likely 

that the proposed design will require a lighter gauge sheet metal for the ductwork compared to 

the initial design. This cost savings was not captured in the analysis. 

Kitchen Exhaust and Clothes Dryer

The original design for kitchen exhaust ventilation was a demand controlled system composed of 

three central exhaust risers with connections to standard kitchen range hoods. A direct-drive, 

variable-speed rooftop fan was specified at each of the risers. BSC investigated the option of 

changing the design to allow direct routing of the kitchen range hoods to the exterior. However, 
66 

MVHfH and the architects’ desire to minimize penetrations through the exterior walls influenced 

BSC’s decision to maintain and further develop the original design. 

The kitchen range hood will be an ENERGY STAR-certified unit. The range hood will be 

connected to a 10 × 10-in. riser via a 6-in. duct. In order to maintain the integrity of the fire-rated 

assembly, an Exhausto subduct riser from Enervex will be installed at the riser connection, which 

is an affordable alternative to installing a fire damper (Figure 62). A subduct is a sheet metal 

boot that is installed inside the riser. It has a 22-in. vertical extension, as stipulated by the 

International Building Code (ICC 2009a), that creates a downward-only pathway from the riser 

to the individual run outs. This extension serves as a barrier against potential fire and smoke 

entrainment from the riser to the run outs.

Figure 62. Exhausto subduct riser and schematic

There will be three 10 × 10-in. risers in the building: two of these risers will service three kitchen 

hoods, and the third riser will service four. All risers will terminate at the roof. A direct-drive, 

variable-speed rooftop fan (GreenVent System from Greenheck) will be installed at each of the 

risers. This fan system is demand controlled. A pressure sensor will be installed in the riser that 

can detect pressure changes in the duct when a range hood is turned on, and activate the rooftop 

fan. The system will adjust the fan speed to maintain a constant negative pressure in the riser, 

thus increasing the airflow when multiple range hoods are turned on. This system also ensures 

that fan flow from the range hoods will not pressurize the riser duct, resulting in contaminant 

transfer to other units. 

Each apartment will have a clothes washer and dryer unit. MVHfH will be installing condensing 

dryers, in order to avoid routing ductwork to the exterior. 
67 

7 Actual Energy Performance Versus Predicted Site Energy Use

Predicted Site Energy Use

BEopt software was utilized to evaluate the cost effectiveness of the retrofit measures proposed 

for this project. Using the optimization feature, alternate options for wall insulation, window 

types, infiltration, and mechanical systems were modeled in order to determine the combinations 

of measures that are the most cost effective. The default cost values for the Chicago Retrofit 

were used for the majority of the inputs. Several cost values were also obtained from RSMeans 

(Reed 2012) and the cost of windows per unit was derived from the estimate provided by Harvey 

Industries. 

The BEopt software includes an optimization capability that uses user-supplied cost data and 

energy use information for a specified set of energy-saving measures to determine combinations 

of measures that are optimal or near optimal in terms of cost effectiveness. BEopt uses a 

sequential searching technique so that not every possible combination of options is simulated. 

One representative apartment unit was modeled (Unit 8, on the second floor), using the selection 

of enclosure and mechanical components shown in Table 14. This unit was chosen for modeling 

because of its simple geometry as well as its exposure to the exterior.

Table 14. Selected Component Options for BEopt Modeling

Component Cases

Exterior Wall 

6 in. of XPS rigid insulation

4 in. of XPS rigid insulation, 

5 in. of ccSPF

2 in. of ccSPF with fiberglass batt insulation

Roof Insulation 

6 in. XPS rigid insulation on the roof deck 

with 6 in. ccSPF in the rafter cavity

6 in. polyisocyanurate on the roof deck 

with 10-in. blown fiberglass in the rafter cavity

6 in. ccSPF installed only in the rafter cavity

Windows

Existing windows with new low-e storm windows 

(U = 0.34, SHGC = 0.48) 

New ENERGY STAR-qualified double-pane units 

(U = 0.30, SHGC = 0.30)

Infiltration “Tighter” (3.3 ACH50)

“Tightest” (1.7 ACH50)

Gas Boiler 80% efficiency

91% efficiency
68 

Table 15 includes a list of enclosure and equipment specifications used as inputs for the energy 

modeling for the “Design Case,” and the options for the “Minimum Cost Case” that were 

selected by the program. The “Design Case” includes measures that were chosen by the design 

team, and bring the percent energy savings based on the lowest cost or free materials and labor. 

The “Minimum Cost Case” consists of selections that bring the highest percent energy savings at 

the lowest upfront cost. Characteristics that differ between these two cases are shown in italics.

Table 15. BEopt “Design Case” Energy Modeling Inputs

Component Design Case Minimum Cost Case

Roof 6 in. XPS + 6 in. ccSPF 6 in. ccSPF

Wall 6 in. XPS inboard of masonry, with 

stud frame wall 2 in. ccSPF + 51⁄2-in. batt insulation 

Basement Wall 3”-3-1⁄2” closed-cell spray foam 

(ccSPF) 3–31⁄2-in. ccSPF

Basement Slab 2 in. XPS 2-in. XPS

Windows New double glazed vinyl windows 

U=0.30, SHGC=0.30

Existing windows with low-e storms 

U=0.34, SHGC+0.30

Infiltration 1.7 ACH50 1.7 ACH50

Heating and 

Cooling 

Gas-fired tankless water heater 

(91%) per unit, with baseboard 

radiation heating loop; no cooling 

provided

Gas-fired tankless water heater 

(80%) per unit, with baseboard 

radiation heating loop; no cooling 

provided

DHW Gas-fired tankless water heater, per 

unit

Gas-fired tankless water heater, per 

unit

Ventilation HRV, individual units (50% of 

ASHRAE 62.2)

HRV, individual units (50% of 

ASHRAE 62.2)

Lighting 100% CFLs 100% CFLs

Appliances ENERGY STAR refrigerator,

dishwasher, clothes washer

ENERGY STAR refrigerator, 

dishwasher, clothes washer

Figure 63 illustrates the graph that plots the average source energy savings per year against the 

annualized energy related costs. The optimal packages are those that form the lower bound of the 

plotted data points and the selected point is the “Design Case.”

As discussed in Section 3 of the report, the practices that are the best approaches for this 

particular project may not be the most cost effective in all cases because of the financial model 

of Habitat for Humanity.
69 

Figure 63. Unit 8 BEopt optimization results—cost versus energy use

The difference in source energy use between the “Existing” and “Design Case” projected by 

BEopt was 98.9 MBtu/yr, or a 53.3% reduction (Figure 64).

Figure 64. Unit 8 BEopt optimization results—average source energy use

Actual Energy Performance

The retrofit work on the apartment units is ongoing and the project is slated for a completion date 

in December of 2014. Therefore, utility bills were not available for the comparison of the 

predicted and actual energy use. 

”Minimum Cost Case”

”Design Case”
70 

8 Construction Cost for Retrofit Measures

Cost values were collected from the project team for a number of the retrofit building 

components (Table 16). Various construction materials have been donated to the project; 

therefore, some of the cost values listed below could not be quantified.

Table 16. Construction Cost for Retrofit Measures

Component Cost

Roof—Sloped and Flat (Demolition, Air Barrier Membrane, 

Labor for XPS Rigid Insulation, Cover Board, Ethylene 

Propylene Diene Monomer (EPDM) Roof Membrane, Shingles)

$53,500

Wall N/A

Basement Wall N/A

Basement Slab (Sand and Gravel, Drainage Mat, Concrete Slab) $8,150

Windows (Double Glazed, Argon Filled, U = 0.30, SHGC = 0.30) $23,804

Heating and DHW $112,222

Ventilation $79,364

Lighting N/A

Appliances (Combo Washer and Dryer) $1,000–$1,200/unit

Roof

The cost includes the removal of the existing roofing from both the sloped and the flat roofs, 

installation and product cost of the air barrier membrane, installation of the donated three layers 

of 2-in. XPS rigid insulation, installation and product cost of the insulation cover board, and the 

installation and product cost of the ethylene propylene diene monomer (EPDM) roof membrane 

and shingles. It does not include the cost of the 6 in. of spray foam shown on the retrofit plan. 

Walls

The cost for the wall retrofit was not available. The three layers of 2-in. XPS rigid insulation and 

the insulation adhesive were donated. The cost of sheathing tape used for taping the seams of the 

rigid insulation was not available. This was due to the variety of tape products used (Dow, 

Tyvek, Lowes; both donated and left over from previous projects). The cost of lumber and 

drywall was not available.

MVHfH has received estimates for the repointing and masonry restoration and repair work that 

will be conducted. This measure is a requirement to control bulk water wetting of the masonry 

wall, due to the retrofit of interior insulation (see Straube et al. 2012). The estimates were in the 

range of $200,000, which is higher than the $100,000 originally budgeted for. 

Basement Walls

The cost for the basement retrofit is not available. The ccSPF insulation will be donated and the 

team has yet to obtain the estimates.

Basement Slab

The cost for leveling the existing dirt floor and slab with sand and gravel was approximately 

$450. The budget for the drainage mat was set for less than $1,000. The team was able to find the 

product for approximately $650, but since it is not available locally the cost of shipping was 
71 

going to be fairly high. The project team was able to negotiate the cost of shipping and obtain the 

product and accessories for approximately $800. The labor cost for casting the concrete slab was 

estimated at $2,850. Forty-five yards of concrete will be needed for the basement slab; the cost 

per yard is $100. Therefore, the cost of the concrete slab will be approximately $4,500. 

Heating and Domestic Hot Water

The cost estimates have yet to be obtained for the designed system; therefore, product costs were 

established through retailers and labor was estimated through discussions with the local plumber 

whom BSC has been working with. 

Ventilation

The cost estimates have yet to be obtained for the designed system; therefore, product costs were 

established through retailers, and labor was calculated per rates stipulated by the RSMeans (Reed 

2012) costing source. 

Lighting

The CFLs will be provided by the ENERGY STAR program. The project team will be able to 

obtain a portion of the lighting for the building from the MVHfH warehouse. Discontinued lines 

of lighting are often donated to MVHfH by a number of manufacturers. The remainder of the 

light fixtures will be purchased.

Appliances

The ENERGY STAR-qualified refrigerators and stoves will be donated by Whirlpool, and 

ENERGY STAR-qualified dishwashers will be supplied by the future homeowners. MVHfH will 

be providing clothes washers and dryers for each unit, because space restrictions and ventless 

drying requirements will play a major role in the selection of the units. The project team is 

considering the all-in-one combo ventless condensing units by LG. The retail cost for those 

compact units is approximately $1,600. However, the project team may have an opportunity to 

purchase all 10 units at a discounted price ($1,100–$1,200 each) from a local dealer. 
72 

9 Conclusion

Overview

In this research report, BSC has evaluated several components of the advanced efficiency 

package implemented in this project. Many aspects were taken into consideration while selecting 

the retrofit measures: occupant comfort, occupant health and safety, building and equipment 

durability, building code compliance, as well as building and equipment maintainability. 

Due to the unique financial model of Habitat for Humanity, some enclosure retrofit measures 

chosen in this project may not be the most cost effective for the majority of multifamily masonry 

buildings. However, because of aspects such as donated materials and volunteer labor, the 

selected retrofit measures were the most cost effective in this specific case.

Brick Material Property Testing and Hygrothermal Simulations

• Does the addition of high levels of interior insulation present a risk of FT damage to the 

mass masonry walls in this building?

Sample bricks were collected from the interior and exterior of the original building as well as the 

addition, and material property testing was performed to inform the assessment of FT risk. 

Several methods of testing were implemented, including dry density, water absorption 

coefficient (A-value), free water saturation, vacuum saturation, and Scrit. The Scrit values, which 

reflect the brick’s resistance to freeze-thaw damage, were relatively high (~0.75–0.80), 

indicating good resistance to damage. The measured values were used in the WUFI software to 

predict the brick moisture content during freezing conditions for the existing and proposed 

retrofit wall assemblies under varying rain exposures.

The resultant moisture content values were compared to the tested critical FT moisture content, 

to assess the risk of damage. Assuming excess external moisture sources (missing downspouts, 

condensate from window mounted air conditioners, etc.) are addressed, the predicted moisture 

contents were well below the critical threshold. Since the risk of FT degradation was low, the 

team recommended retrofit of interior insulation. 

Applying the results of the masonry retrofit analysis to a wider array of projects is beyond the 

scope of this report; an overview of the topic is covered by Straube et al. (2012). The analysis of 

the applicability of material property testing to similar projects is covered in an upcoming BSC 

report; it takes the database of Scrit measurements, and determines whether larger patterns can be 

found based on more easily measured material properties (dry density, porosity, liquid water 

uptake) or other characteristics, such as vintage, geographic location, or manufacturing method. 

Predicted Energy Performance and Cost Impacts of Proposed Wall Retrofit 

Design

• What are the predicted energy performance and cost impacts of the proposed wall retrofit 

design (6 in. of XPS) versus the other considered strategies (spray foam, flash, and batt)? 

There were a number of insulating options that would be well suited for this masonry building 

and were being considered for this project. The project team decided to explore the following 

options for the wall retrofit: three layers of 2-in. XPS rigid insulation, two layers of 2-in. XPS 
73 

rigid insulation, 5 in. of ccSPF, and 2 in. of ccSPF with batt insulation. Each of those wall 

systems offered certain advantages and disadvantages.

Using the parametric feature in BEopt, alternate options for wall insulation were modeled to 

determine the energy use of each option and the most cost-effective measure. Based on the 

energy modeling, it was determined that 6 in. of XPS rigid insulation wall system option would 

provide the best energy performance, although 5-in. ccSPF and 2-in. ccSPF with 5.5-in. 

fiberglass batt had roughly equivalent performance. However, the 6 in. of XPS option was found 

not to be the most cost effective; the 2-in. ccSPF with 5.5-in. fiberglass batt was judged to be the 

best value for performance. However, the 6-in. XPS wall was selected at this project as the best 

suited option, given Habitat of Humanity’s financial model, which includes volunteer labor and 

donated materials. 

Impact of Rebates and Incentives on Decision Making Process

• How do rebates and incentives impact the decision making process of the builder, 

especially in cases of budget constrained construction projects? In addition, how do these 

impact the overall energy performance? 

Due to the budget constraints for this project, the MVHfH team needed to maximize the 

available incentives. The team explored all of the available incentive programs in the state of 

Massachusetts to help fund the energy efficiency retrofit measures. It was important for the 

project team to establish the goals that were achievable at the start of the construction process 

and eliminate features that were not attainable, and would not have significant impact on the 

performance of the building. Through the energy modeling performed for each of the units, the 

project team was able to select the appropriate measures to be implemented in the building. The 

analysis from the modeling also helped inform decisions that will impact the overall performance 

of each of the units. 

The most substantial incentive for this project was meeting the requirements for ENERGY 

STAR Qualified Homes, Version 3 Tier II. The threshold for this level is 30% better than the 

modeled User Defined Reference Home; it is associated with a Massachusetts incentive of 

$1,150 per unit. 

Retrofit Air Barrier Strategies and Assemblies

• What is the effectiveness of air barrier strategies implemented in this multifamily retrofit 

project, and what were the difficulties in implementation? 

Effective air barriers are vital for good energy performance; compartmentalization (separation 

between units) is important for reducing sound, odor, and smoke transmission, and limiting 

stack-driven airflows. Therefore, BSC established targets and developed details for interior-toexterior air barriers and compartmentalization, specific to an interior insulation retrofit of a 

multifamily mass masonry building. In addition, installation by a volunteer workforce had to be 

taken into account. 

Air barrier details were developed using the layers of interior rigid XPS insulation as the air 

barrier at the walls; details were required at window and other penetrations. Retrofit roof and 

below-grade air barrier details were also developed. Compartmentalization details, which also 
74 

met fire resistance ratings were developed, including floor-to-floor (at exterior wall), partition 

walls (within units), and demising walls (separating units). To help the team to put these details 

in context, a table was made showing the relevant interface detail between the air barrier 

assemblies (wall, ceiling, and floor). In addition, an outline-form narrative was included with the 

air barrier details, to give the team a greater understanding of the compartmentalization strategies

being implemented. 

Retrofit Mechanical Design

• What are the cost impacts of implementing a compartmentalized ventilation strategy with 

individual apartment HRV systems versus a traditional large single central HRV system?

• What are the cost impacts of using individual unit combination space heating/hot water 

units, including distribution piping design and installation specifics? 

Compartmentalized mechanical systems offer numerous advantages over centralized strategies, 

such as lower installed cost, more efficient operation and occupant control. Therefore, individual 

ventilation and hydronic heating strategies were developed for this retrofit building. 

The hydronic/DHW system consists of an individual combination space heating/DHW boiler 

with convectors (radiators) that are rated for low supply water temperature. This design will 

ensure that the boiler is consistently condensing, ensuring high efficiency operation. The current 

design saves only a nominal amount in terms of installed cost ($430); however, the current 

system is expected to save around $400/yr in heating and DHW costs for the entire building. 

These predicted savings are associated with the boiler’s capacity to operate in condensing mode 

due to the improvements in the distribution system. 

The ventilation design consists of small individual HRVs installed in mechanical closets in each 

apartment. A small duct system serves as the distribution system. The compartmentalization of 

the HRV system results in a significantly cheaper design and individualized ventilation control in 

each apartment. The current ventilation design saves an estimated $36,000 (a 30% reduction) 

compared to the original centralized design. These savings can be attributed to the elimination of 

fire-rated shafts, extensive unit-to-unit ductwork, and fire dampers (where ductwork penetrates 

rated assemblies).

Actual Energy Performance Versus Predicted Site Energy Use

• How does the actual energy performance (i.e., utility bills) compare to the BEopt 

predicted site energy use? 

Energy analysis with BEopt software was performed for one of the units with several options for 

wall insulation, window types, infiltration, and mechanical systems in order to determine the 

combinations of measures that are the most cost effective. The results showed a 53% reduction 

source energy use between the “Existing” and “Design Case.”

No units have been completed to date and the project is slated for a completion date of December 

2014. In order to provide a valuable dataset of the actual energy use, utility bills after the first 

full winter would need to be collected and analyzed. However, no additional work is planned for 

this project in the subsequent years due to the termination of funding at the end of 2012. 
75 

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ASHRAE. (2008). Handbook—HVAC Systems and Equipment. Atlanta, GA: American Society 

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ASHRAE. (2010). ASHRAE Standard 62.2—Ventilation and Acceptable Indoor Air Quality in 

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Fagerlund, G. (1977). “The Critical Degree of Saturation Method of Assessing the Freeze/Thaw 

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Code Council. 

Lstiburek, J.W. (2000). Toward an Understanding and Prediction of Air Flow in Buildings. 

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GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.

Lstiburek, J.W. (2005b). “Multifamily Buildings: Controlling Stack-Driven Airflows.” ASHRAE 

Journal 47:30–38. Atlanta, GA: American Society of Heating, Refrigerating and AirConditioning Engineers, Inc. 
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Lstiburek, J.W. (2007). “Building Sciences: The Perfect Wall.” ASHRAE Journal 49:74–78. 

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Lstiburek, J.W. (2009). “Building Sciences: Complex 3-D Airflow Networks.” ASHRAE Journal

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Engineers, Inc.

Lstiburek, J.W. (2010). “Building Sciences: Thick as a Brick.” ASHRAE Journal 52:50–56. 

Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. 

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Mass Save. (2012). “Massachusetts New Homes with ENERGY STAR Eligibility 

Requirements.” www.masssave.com/residential/building-a-house-oraddition/requirements/energy-star-homes-eligibility-requirements. Accessed October 24, 2012. 

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Rudd, A., Ueno, K.; Bergey, D.; Osser, R. (2011). “Report on the Expert Meeting for 

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Appendix A: MVHfH Site Assessment
 

 

August 15, 2011 

Emerson Dahmen 

Merrimack Valley Habitat for Humanity 

emerson@merrimackvalleyhabitat.org 

Re:	 Building Science Consulting Services: Site Evaluation 

100 Parker Street, Lawrence, MA 

Dear Mr. Dahmen: 

1. Summary 

The existing masonry building at 100 Parker St. Lawrence MA was visited Wednesday August 3rd 2011. The general 

conditions of the site were inspected; the extent of the planned renovations discussed, and brick samples taken for testing. 

2. Existing Conditions 

The building consists of original building fronting Parker St. and a rear addition. A small third addition is being demolished as 

part of the renovation. The remainder of the building has now been gutted, including essentially all HVAC, plumbing, 

electrical, partition walls, and interior finishes. The building originally housed a convent. The rear addition has reportedly 

been left vacated and unheated for 2-3 recent years. The building has been purchased by Merrimack Valley Habitat for 

Humanity, and is in the process of being renovated to produce 10 three bedroom condominium units. 

Figure 1: Aerial photo of site and parts of the building 

Existing Addition 

Building 

Demolished 

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2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Original Building Walls 

The original building façade consists of three brick wythe mass wall construction. 

Figure 2: Original building – view of masonry wall section where doorway was shifted to interior 

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2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 3: Original building –front entrance 

	 The front entrance is to be restored to original appearance. Although the entrance incorporates a low slope roof 

against the masonry, there does not appear to be brickwork damage at the interface. 

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2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 4: Original building – general view of building frontage. 

	 A false (meaning it only extends one brick course inward) granite stone belt course extends around the top of the 

basement and the second story which do not have drip edges. 

	 The window brow headers do not appear to function to divert surface rain water from the windows. 

	 The window sills include sloping end dams but do not have undercut drip edges, however, excessive deterioration does 

not appear under the sills. 

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Figure 5: Original building – close up of brick courses 

 Every fifth course of bricks is inset an inch. 

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2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 6: Original building – façade to ground interface 

	 The masonry wall is buried 2 or 3 brick course below the finish grade around a significant portion of the building 

perimeter 

	 Although the original façade design has a number of troublesome details (low slope roof against façade, lack of drip 

edges, water concentrating window headers, stepped masonry courses) and grade is now above the bottom courses of 

brick, there does not appear to be associated visible damage. These observations would suggest that the building is 

well protected from driving rain and that the ground is well drained. 

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2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 7: Original building: brickwork spalling and surface efflorescence 

	 A spalled brick was found sitting on the lower belt course. Suspect rain water concentration from the inadequately 

flashed window. 

Figure 8: Original building: brickwork and mortar damage below belt course 

	 In Figure 8 the scupper was filled with debris and roof water was apparently running down the face of the brick and 

concentrating below the belt course, especial at the joints which have eroded mortar joints. The tops of the belt 

course are flat, and hence, water flowing down the face of the brick above flow in behind the belt course. This 

interface has been caulked at some point, which has been ineffective. 

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2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 9: Original building – missing downspout 

 The missing downspout should obviously been replaced and the resulting damage is clearly visible. 

Original Building Roof 

The sloped roof areas have slate shingles. The center of the building has a flat roof which has a small clerestory with an 

exhaust fan (likely intended to assist natural ventilation). The flat roof section of the building has no parapet or roof drain. 

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2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 10: Original building – flat roof area 

	 The roof appeared in good shape beside issues with the scuppers and down spouts. The project team is planning 

to replace the slate shingles with “slate” like asphalt shingles. A new fully adhered EPDM membrane for all flat roof 

areas on the original building. 

Figure 11: Original building – clerestory 

	 The project team is planning on replacing the clerestory with ductwork to a fire exhaust fan. 

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2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 12: Roof drain filled with debris 

	 The rain water runs to scuppers emptying in external downspouts. The scuppers were apparently not maintained, 

clogged, and led to water loading on the façade contributing the damage shown in the previous figures. 

Original Building Windows and Doors 

The windows are a mix of double pane vinyl and wood framed windows. The windows sit within wood framing. The lintels 

are a mix of steel in some cases and wood in others. None of the lintels are planned for replacement, the wood framed 

windows are planned for replacement and the vinyl windows are currently not planned for replacement. 

	 The vinyl windows appear dated and do not have a low-e coating (based on simple LED light reflection test). 

	 The doors have single pane windows and installed in wood frame assemblies with little or no insulation or an air 

barrier. 

	 The doors and windows appear to be installed with fiberglass filling the gap between the window frames and the 

rough framing. Poor air tightness is suspected and these interfaces. 

Original Building Interior 

The interior has been brought down to masonry and subflooring exposing the structure. 

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2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 13: Floor joists set in masonry wall 

	 Some floor joists are being sistered as shown in Figure 13 to stiffen the floor. Emerson indicated that they are 

planning to build a 2x4 wood on the inside but not planning to use this as a bearing wall. 

Figure 14: Original building - floor joist to masonry wall interface 

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2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

	 There has been an attempt press mortar in around the perimeter the joist where they enter the masonry. 

However, cracks which are in some case substantial have formed around the mortar-wood interface at most 

joists. 

	 Floor joists are fire cut and sit in the innermost course of the bricks. The condition of the wood at the end of 

these joists was confirmed to be in good condition by stabbing with a flat screw driver. Emerson says he has 

tested the wood on samples throughout the building with good results. 

Figure 15: Original building – interior view of sloped roof 

12 

22 

90
2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

~ 8” 

Figure 16: Original building – interior view of sloped roof 

The available thickness for insulation on the interior of the sloped roof sections is limited at window frames. Where 

inspected there appeared to be 8” from the existing interior trim to the underside of the sheathing. 

13 

22 

91
2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 17: Original building – basement 

The basement appeared dry and no evidence of previous water leakage issues was observed. 

14 

22 

92
 

 

 

2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Addition Walls 

The addition façade has a matching face brick to the original building and mostly similar architectural features. 

Figure 18: Addition - North Façade 

Figure 19: Addition - South Façade (left) and East Façade (right) 

15 

22 

93
 

2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 20: Bricks and belt course pushing out on north façade 

	 It is not clear from visual inspection why the façade is pushing out at the top of the north most addition façade. 

Emerson indicated that the structural engineer did not anticipate the problem being due to building movement. It 

may be due to expansion of the inner brick courses due to freeze thaw spalling pushing out the face bricks and 

stone course. 

Figure 21: Addition: cracks in brickwork 

16 

22 

94
 

 

2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

	 Significant cracks have formed in masonry mostly at the edge of window sills and headers. Emerson relayed that 

the structural engineer’s opinion was that mortaring the cracks would be adequate and that it did not appear that 

future building settlement or movement would cause significant further damage. 

Addition Roof 

The addition roof area is completely low sloped roof. The roof has a gradual slope to a center drain. The cap of the 

concrete parapet slopes inward. The roof is punctured by a couple of skylights and various mechanical vents. The drawings 

call for a new fully adhered EPDM roof and sheathing replacement/patching where needed. 

Figure 22: Addition – Roof 

Figure 23: Addition – limited space for insulation below door to roof (approximately 6”) 

	 One potential limitation to amount of insulation to be added to the top of the roof in the space available below the 

access door (approximately 6”). 

Addition Windows and Doors 

The addition has vinyl windows. The windows and doors have similar issues as in the original building. 

17 

22 

95
2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 24: Addition - a typical window 

Addition Above Grade Interior 

It can be seen from the interior that the wall system is composed of a face brick on the exterior and the interior consisting of 

either 

1. Clay Tile 

2. Concrete Block, or 

3. Two Layers of Brick 

18 

22 

96
2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 25: Addition – views of various interior materials used in masonry mass walls 

19 

22 

97
2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 26: Addition – underside of roof 

 A deck consisting of 2x10 boards sits below the roofing 

Figure 27: Addition – floor joists sitting in masonry and window 

 Roof and floor joists are set in the masonry similar to the original building. 

20 

22 

98
 

2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

Figure 28: Addition – interior view of a crack in the masonry mass wall 

Figure 29: Addition - basement 

21 

22 

99
2011-08-15 Site Evaluation: 100 Parker Street, Lawrence, MA 

3. Closure 

There appears to be existing freeze thaw damage on the masonry façade. BSC will provide brick testing and analysis to 

assess the potential freeze of further damage due to recommend wall insulation options. However, insulating the walls will 

definitely not address the existing problems. BSC will work with the architect to architectural detailing to address these 

issues. 

Please note that Honorata Wytrykowska will be our main contact for provide construction support. 

If you have any questions regarding our assessment please feel free to call or email. 

Regards, 

Randy Van Straaten 

Building Science Consulting Inc. 

167 Lexington Court, Unit 5 

Waterloo, ON N2J 4R9 

office 519.342.4731 

cell 519.319.9773 

fax: 978-589-5103 

Building Science Corporation 

Somerville MA | Waterloo ON 

www.buildingscience.com 

22 

22 

100
101 

Appendix B: MVHfH Retrofit Construction Details
 102

RAILING INSTALLATION PER 


MANUFACTURER'S STANDARD DETAIL 


EXISTING CONCRETE 


CAP TO BE REMOVED 


NEW PRESSURE TREATED 


WOOD BLOCKING FASTENERS, 


PROVIDE AS NEEDED 


NEW MASONRY ANCHORS, 


PROVIDE AS NEEDED -~~ 

NEW SHEET METAL COPING OVER NEW 

PRESSURE TREATED WOOD BLOCKING, 

SLOPED TO DRAIN TO ROOF -~­

NEW PRESSURE TREATED WOOD 

BLOCKING, PROVIDE AS NEEDED ------------+ 

NEW FULLY-ADHERED ROOF 


MEMBRANE, LAP OVER PRESSURE 


TREATED WOOD BLOCKING MIN. 4", 


INSTALL PER MANUFACTURER'S 


RECOMMENDATIONS--~--------~! =~ 

NEW FULLY-ADHERED AIR 

BARRIER TO MEMBRANE, TOP OF PLYWOOD EXTEND ----+----------~~ ~-==~ 

NEW CANT, INSTALL PER ROOFING 

MANUFACTURER'S RECOMMENDATION ---+--------~- II===: 

NEW~· INSULATION COVER BOARD 

NEW~· PRESSURE TREATED PLYWOOD --tf=b¥¥=fbfe~~~~~=~ 

NEW (3) 2" LAYERS OF DOW XPS RIGID ---1~~~~­ INSULATION, JOINTS STAGGERED 

NEW 2x6 MIN. WOOD NAILER 


ATTACHED TO SUBSTRATE, OVERALL 


THICKNESS TO MATCH INSULATION 


EXISTING BOARD SHEATHING OR 


SHEATHING PATCH 


(MATCH EXISTING THICKNESS) 


NEW 6" CLOSED-CELL (2.0 pcf) 


SPRAY FOAM INSULATION 


EXISTING ROOF JOISTS 

ROOF PARAPET 1 


SCALE: 1112" =1'·0" 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

Merrimack Valley Habitat for Humanity Sheet Title: 

Roof Details 

Date: 2012-02-06 RP1 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 103

NEW SEALANT (IF REQUIRED FOR 


THE SPECIFIC SYSTEM) 


NEW PERIMETER EDGE METAL 


FLASHING 


NEW SEALANT WATER BLOCK 

NEW SELF-ADHERED MEMBRANE 


FLASHING {EXTEND MIN. 2" 


BEYOND EDGE OF GRAVEL STOP) 


NEW FULLY-ADHERED ROOF 


MEMBRANE, EXTEND DOWN MIN. 6" 


OVER SLOPED ROOF 


NEWWINSULATION COVER BOARD 

NEW (3) 2" LAYERS OF DOW 


XPS RIGID INSULATION, 


JOINTS STAGGERED ---+'--t---"-+-'~ 

NEW 6" CLOSED-CELL {2.0 pcf) 


SPRAY FOAM INSULATION 


EXISTING ROOF JOISTS 

NEW SHEET METAL FLASHING 

NEW ASPHALT SHINGLES 

NEW FULLY-ADHERED 


ROOF MEMBRANE 


ROOF PARAPET 2 

SCALE: 1 112" =1'·0" 

Merrimack Valley Habitat for Humanity 

Roof Details 

Date: 2012-02-06 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

Sheet Title: 

RP2 
 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 104

NEW SEALANT (IF REQUIRED FOR 

THE SPECIFIC SYSTEM) 

NEW PERIMETER EDGE METAL 

FLASHING 

NEW SEALANT WATER BLOCK 

NEW SELF-ADHERED MEMBRANE 

FLASHING (EXTEND MIN. 2" 

BEYOND EDGE OF GRAVEL STOP) 

NEW FULLY-ADHERED ROOF 

MEMBRANE, EXTEND DOWN MIN. 6" 

OVER SLOPED ROOF 

NEWX" INSULATION COVER BOARD 

NEW (3) 2" LAYERS OF DOW XPS RIGID 

INSULATION, JOINTS STAGGERED 

EXISTING BUILT-UP ROOF AS AIR 

BARRIER, REPAIR TO CREATE 

AIRTIGHT LAYER NEEDED 

EXISTING BOARD SHEATHING OR 

SHEATHING PATCH 

(MATCH EXISTING THICKNESS) 

NEW STRIP OF FULLY ADHERED ROOF 

MEMBRANE, EXTEND DOWN MIN. 12" 

OVER SLOPED ROOF 

NEW 2x6 MIN. WOOD NAILER 

ATIACHED TO SUBSTRATE, OVERALL 

THICKNESS TO MATCH INSULATION 

NEW 6" CLOSED-CELL (2.0 pel) 

SPRAY FOAM INSULATION 

EXISTING ROOF JOISTS 

NEW SHEET METAL FLASHING 

NEW ASPHALT SHINGLES 

NEW FULLY-ADHERED 

ROOF MEMBRANE 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

ROOF PARAPET 2 - ALT 

SCALE: 1 112" =1'·0" 

Merrimack Valley Habitat for Humanity 

Roof Details 

Date: 2012-02-06 

Sheet Title: 

RP2-ALT 
 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 105

NEW ROOF DRAIN DOME AND ROOF 

DRAIN EXTENSION 

NEW ROOF MEMBRANE 

SITE-FABRICATED INTO ROOF 

DRAIN SLEEVE {UPSIDE-DOWN PIPE 

BOOT CONSTRUCTION}, HEAT WELD 

TO EXTENDED SECTION OF MAIN 

ROOF MEMBRANE 

NEW FULLY-ADHERED ROOF 

MEMBRANE, EXTEND OUT 1" OVER 

ROOF DRAIN EXTENSION FLANGE 

NEW~"INSULATION COVER BOARD 

NEW {3) 2" LAYERS OF DOW XPS 

RIGID INSULATION, JOINTS 

STAGGERED, SLOPE TO MEET 

EXISTING ROOF DRAIN FLANGE, 

START NEW SLOPE 2'-0" FROM 

ROOF DRAIN 

NEW FULLY-ADHERED AIR BARRIER 

MEMBRANE, CONTINUE OVER TOP 

OF EXISTING ROOF DRAIN FLANGE 

{UNDER GASKET) 

EXISTING ROOF DRAIN FLANGE 

NEW SILICONE SEALANT 

CONTINUOUS AT TOP OF BOTTOM 

EXTENSION TO THREADS OF TOP 

EXTENSION 

EXISTING BOARD SHEATHING OR 

SHEATHING PATH 

{MATCH EXISTING THICKNESS) 

ROOF EXTENSION DRAIN 


SCALE: 1 112" =1'·0" 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

Merrimack Valley Habitat for Humanity Sheet Title: 

Roof Details 

Date: 2012-02-06 RD COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 106

-----

EXISTING OR NEW ROOF 


PENETRATION 


NEWSEALANT~ 

NEWSHEETMETALCOLLAR 

NEW SEALANT 

-~ 

NEW SHEET METAL COLLAR 

NEW SHEET METAL FLASHING ---...__ 

NEW FULLY-ADHERED ROOF 


MEMBRANE, SEAL TO SIDE OF 


PENETRATION, EXTEND 6" ABOVE 


INSULATION COVER BOARD ------..------­

--:--.---:-- -...·::.·.·:.··•::.·.·---·-·.·:.·.-.-··.·:=---·-·.·:::··.-.-.-:...".".". 1 ~ -- ;----;­ I --- -- t~::; ----;·--:- --~---- t;:--1"--- ·:·t;·- ::

?T1 1 1 1 1 1 1 1_l 1 1 1 1 I 

COVER BOARD 

NEW~· INSULATION 1 1 1 1 1 1 1

I I I I I I J...-1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I l I l I 

I I LJ I I I I 

(3) 2" LAYERS OF DOW XPS RIGID I I I I I I I I I 

I 

I I I I I I 

I 

I I 

I 

... ~~~~~~~~~~~~~~~ JJ I I

INSULATION, JOINTS STAGGERED, 1!:----------

I 

I 

I 

I 

----.:-.:.- __------..------:-------- _____-:.:-------------=----------~---------.:--------·.:-:.-------- _____..________________________..__ ---...-----------------------..:-----------..:-----------------------­ SLOPE X" PER FOOT TO ROOF DRAINS --­ NEW FULLY-ADHERED AIR BARRIER 


MEMBRANE, SEAL TO SIDE OF 


PENETRATION, EXTEND 2" ABOVE ./ >" ~ INSULATION COVER BOARD_______/ 


EXISTING BOARD SHEATHING OR /T // 

SHEATHING PATCH / // _ 


(MATCH EXISTING THICKNESS) _______/ 


NEW 

SPRAY 

6" CLOSED-CELL 

FOAM INSULATION____/ 


(2.0 pcf) ~/.

EXISTING ROOF JOISTS 

v 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

ROOF VENT INSTALLED BEFORE ROOF COMPLETION 

SCALE: 1 112" =1'-0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Roof Details 

Date: 2012-02-06 RV COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 107

----------

---------

EXISTING OR NEW ROOF 


PENETRATION 


NEWSEAI.ANT~ 

NEW 

NEWSHEETMETALCOLLAR 

SHEET METAL 

NEW SEALANT 

COLLAR 

~ 

NEW SHEET METAL FLASHING ---..__ 

NEW FULLY-ADHERED ROOF 


MEMBRANE, SEAL TO SIDE OF 


PENETRATION, EXTEND 6" ABOVE 


INSULATION COVER BOARD --:±--------------------~11 -j-co• 

-------.:­ -------------------:-------=----..-------------------------------------=--­ ----------..-----------------------------------..-------------------------------------.:--------:------­ I I I I I I I I I I I I I I I I I I I I 

NEW ~~~~~~j!~~ _____/ I I I I I I I I I I I I I I 11 I~ I I 

I I I I I I ..J•...I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I l I 1 I 

(3) 2" LAYERS OF DOW XPS RIGID I I /(""_:__1 I I I I I I I 

INSULATION, JOINTS STAGGERED, Vi I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 


SLOPE /'4" PER FOOT TO ROOF DRAINS ____....o~; _ _ _ - _-­ ------------------.:-----------..-------:-------------:--.:---:_-_____-:;-----------..-------.:---.:---­ ----------.:-----------.:----------- ----------.:-----------:--------_-_.._-_--------"'----------.:-­ SL 

NEW FULLY-ADHERED AIR BARRIER 


MEMBRANE, SEAL TO SIDE OF 


PENETRATION, EXTEND 2" ABOVE 


INSULATION COVER BOARD, OR EXISTING ~ ~ '"' 

BUILT-UP ROOF AS AIR BARRIER __/8:}:CQ'$-ili~2:::!" ~£::Q:i..l:ilili(:1

EXISTING BOARD SHEATHING OR /' // 


SHEATHING PATCH (MATCH EXISTING / / _ 


THICKNESS) TO BE CUT AWAY TO §A~/...__,.L-~---------11 

ACCOMMODATE NEW VENT PIPE / / 

NEW 6" CLOSED-CELL (2.0 pcf) 


SPRAY FOAM INSULATION 


EXISTING ROOF JOISTS 

CJ 


GRAY TONE INDICATES 


EXISTING STRUCTURE 


ROOF VENT INSTALLED AFTER ROOF COMPLETION - ALT 

SCALE: 1 112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Roof Details 

Date: 2012-02-06 RV-ALT COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 108

(3) 2" LAYERS OF DOW XPS 

RIGID INSULATION, JOINTS 

STAGGERED, TAPE JOINTS 

OF OUTER LAYER EXISTING SEALANT TO BE 


REPAIRED 


NEW2x4STUD 


NEW SEALANT 


EXISTING BRICK WALL 


EXISTING TRIM OVERCL.ADDING 


NEW%" TYPE X TO BE CLEANED AS NEEDED 


GYPSUM BOARD 
 TO PROVIDE SMOOTH 

SURFACE FOR NEW FLASHING 

NEW SPRAY FOAM SEAL 

BETWEEN INSULATING MEMBRANE AND TAPE --~ 

SHEATHING AND EXISTING NEW TRIM 


WINDOW 
 OVERCLADDING ------"<:---1 

EXISTING GRANITE LINTEL 

FILL VOID WITH 


SPRAY FOAM 


EXISTING WOOD TRIM TO 

BE REFURBISHED, CLEAN, 

SCRAPE LOOSE PAINT, 

REPAIR WOOD DAMAGE, 

AND REFINISH AS NEEDED 

TO PROVIDE SMOOTH 

SURFACE FOR NEW 

FLASHING MEMBRANE, 

EXTEND UP TO GRANITE 

LINTEL 

EXISTING SEALANT TO BE 


REPAIRED 


NEW SEALANT ---..L 

NEWT~M~~CLAOO~G~~~~~{~n~;;;;~;;;;~~~~~~~~~j~~---~ EXISTING TRIM 


OVERCL.ADDING TO BE 


CLEANED AS NEEDED TO 


PROVIDE SMOOTH 


SURFACE FOR NEW 


FLASHING MEMBRANE 


AND TAPE 


PRESSURE TREATED 

BLOCKING FOR 

ATIACHMENT OF NEW 

OVERCL.ADDING AND NEW 

STORM WINDOW 

FLASHING TAPE 


EXISTING WINDOW TO 


NEW SEALANT BE REINSTALLED 


NEW SHEET MEMBRANE 


HEAD FLASHING, TURN 


DOWN 2" OVER JAMB 


NEW BACKER ROD AND CJ 

SEALANT OR LOW­ GRAY TONE INDICATES 

EXPANSION SPRAY FOAM EXISTING STRUCTURE 

WINDOW HEAD 

SCALE: 3" =1'.{1" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Window Details 

Date: 2012-02-06 WH COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 109

NEW INTERIORWOOD 


WINDOW SILL AND APRON 


NEW2x4STUD 

NEW%"TYPEX 

GYPSUM BOARD 

EXISTING WINDOW TO 


BE REINSTALLED 


NEW SEALANT 

FLASHING MEMBRANE 


BACK DAM TURNED UP 


WITH PAPER BACKING 


NEW SHEET MEMBRANE 

SILL FLASHING, TURN UP 2" 

AT JAMB AND DOWN OVER 

THE WOOD SILL, JAMB 

FLASHING TO SHINGLE-LAP 

OVER TURNED-UP SILL 

FLASHING, EXTEND OVER 

EXISTING SILL 

OVERCLADDING 

NEW SEALANT -~~ 

NEW STORM WINDOW ---L 

NEW SILL OVERCLADDING, 

PROVIDE WEEP HOLES AT 

THE BASE ----rl""""',..lr-llll 

EXISTING SILL 


OVERCLADDING TO BE 


CLEANED AS NEEDED TO 


PROVIDE SMOOTH 


SURFACE FOR NEW 


FLASHING MEMBRANE 


NEW SEALANT 

MEMBRANE COMPATIBLE 


MASTIC, BUTTER THE 


EDGES OF MEMBRANE 


SILL FLASHING 


EXISTING GRANITE SILL 

EXISTING WOOD SILL TO 


BE REFURBISHED, CLEAN, 


SCRAPE LOOSE PAINT, 


REPAIR WOOD DAMAGE, 


AND REFINISH AS NEEDED 


TO PROVIDE SMOOTH 


SURFACE FOR NEW 


FLASHING MEMBRANE 


FILL VOID WITH 

SPRAY FOAM 

EXISTING BRICK WALL 

NEW SPRAY FOAM SEAL 


BETWEEN STRIP OF 


INSULATING SHEATHING 


AND EXISTING WINDOW 


WINDOW SILL 

SCALE: 3"- 1'.{1" 

NEW SILL OVERCLADDING, PROVIDE 


WEEP HOLES AT THE BASE 


NEW SHEET MEMBRANE SILL FLASHING, TURN 

UP 2" AT JAMB AND DOWN OVER THE WOOD 

SILL, JAMB FLASHING TO SHINGLE- LAP OVER 

TURNED-UP SILL FLASHING, EXTEND OVER 

EXISTING SILL OVERCLADDING ' _..­

NEWSEALANT~t=~~l-~~~~---1 

MEMBRANE COMPATIBLE 

MASTIC, BUTTER THE 

EDGES OF MEMBRANE 

SILL FLASHING 

(3) 2" LAYERS OF DOW XPS RIGID 

INSULATION, JOINTS STAGGERED 

AND TAPED 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

Merrimack Valley Habitat for Humanity Sheet Title: 

Window Details 

Date: 2012-02-06 ws COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 110

NEW%" TYPE X GYPSUM BOARD 

NEW2x4STUD 

{3) 2" LAYERS OF DOW XPS 


RIGID INSULATION, JOINTS 


STAGGERED, TAPE JOINTS 


OF OUTER LAYER 


NEW SPRAY FOAM SEAL 


BETWEEN INSULATING 


SHEATHING AND EXISTING 


WINDOW 


EXISTING WEIGHT POCKET, 


FILL WITH 2" XPS INSULATING 


SHEATHING AND SPRAY FOAM 


METAL ANGLE FOR GYPSUM 


BOARD ATIACHMENT 


APLE FLASHING MEMBRANE TO 


EXISTING WINDOW FRAME 


NEW BACKER ROD AND 


SEALANT OR LOW­


EXPANSION SPRAY FOAM 


EXISTING WINDOW TO BE 


REINSTALLED 


NEW SHEET MEMBRANE 


FLASHING, SHINGLE-LAP OVER 


TURNED-UP SILL FLASHING, 


EXTEND ONTO FACE OF 


EXISTING OVERCLADDING 


EXISTING WOOD FRAME TO BE 


REFURBISHED, CLEAN, SCRAPE 


LOOSE PAINT, REPAIR WOOD 


DAMAGE, AND REFINISH AS 


NEEDED TO PROVIDE SMOOTH 


SURFACE FOR NEW MEMBRANE FLASHING -----'~ ~=:::?==~=4

NEW SEALANT ---F;;;;::;::::::::::::::=:::;!; 

FLASHING TAPE ---{=======~~~=1J EXISTING TRIM OVERCLADDING 


TO BE CLEANED AS NEEDED TO 


PROVIDE SMOOTH SURFACE 


FOR NEW FLASHING 


MEMBRANEANDTAPE---~1 ====~~~~~~~~~ PRESSURE TREATED F 


BLOCKING FOR ATIACHMENT 


OF NEW OVERCLADDING AND 


NEW STORM WINDOW 

NEW STORM WINDOW 

NEW TRIM OVERCLADDING, 


WEEP HOLES AT THE BASE 


EXISTING GRANITE SILL 

EXISTING BRICK WALL 

WINDOW JAMB 

SCALE: 3" 1'.{1" 

EXISTING SEALANT 


TO BE REPAIRED 


PRESSURE TREATED 

BLOCKING FOR ATIACHMENT 

OF NEW OVERCLADDING AND 

NEW STORM WINDOW ---+-----' 

NEW TRIM OVERCLADDING, 


PROVIDE WEEP HOLES AT 


THE BASE -~:=::::!!::==::::;:::;::l 

NEW SEALANT --~------:!U 

EXISTING SEALANT TO BE REPAIRED 

NEW SEALANT 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

Merrimack Valley Habitat for Humanity Sheet Title: 

Window Details 

Date: 2012-02-06 WJ COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 111

NEW (3) 2" LAYERS OF DOW XPS RIGID 

INSULATION, JOINTS OFFSET AND 

TAPED, OUTER LAYER AS AIR BARRIER --=---------------~ 

EXISTING OR NEW WOOD 


FLOORING 


EXISTING WOOD SUBFLOOR CUT 


AWAY 6 ~· FROM THE WALL 


EXISTING OR NEW 


WOOD FLOOR JOIST 


EXISTING STRAPPING TO REMAIN 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

TYPICAL FLOOR ASSEMBLY BETWEEN UNITS -STEP 1 

SCALE: 1112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W1a-1 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 112

NEW {3) 2" LAYERS OF DOW XPS RIGID 

INSULATION, JOINTS OFFSET AND 

TAPED, OUTER LAYER AS AIR BARRIER -------------.! 

NEW STRIP OF MOLD RESISTANT 


FIRE RATED GYPSUM BOARD 


EXISTING OR NEW WOOD 


FLOORING 


EXISTING WOOD SUBFLOOR CUT 

AWAY 6X" FROM THE WALL 

EXISTING OR NEW 


WOOD FLOOR JOIST 


NEW STRIPS OF MOLD RESISTANT FIRE 

RATED GYPSUM BOARD, MATCH 

THICKNESS TO EXISTING STRAPPING 

AND NEW RESILIENT CHANNELS --t-~::::::::~-

EXISTING STRAPPING TO REMAIN 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

TYPICAL FLOOR ASSEMBLY BETWEEN UNITS -STEP 2 

SCALE: 1112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W1a-2 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 113

NEW (3) 2" LAYERS OF DOW XPS RIGID 


INSULATION, JOINTS OFFSET AND 


TAPED, OUTER LAYER AS AIR BARRIER -------------L 


NEW SPRAY FOAM INSULATION 

NEW STRIP OF MOLD RESISTANT 


FIRE RATED GYPSUM BOARD 


EXISTING OR NEW WOOD 


FLOORING 


EXISTING WOOD SUBFLOOR CUT 

AWAY 6 X" FROM THE WALL 

EXISTING OR NEW 


WOOD FLOOR JOIST 


NEW STRIPS OF MOLD RESISTANT FIRE 


RATED GYPSUM BOARD, MATCH 


THICKNESS TO EXISTING STRAPPING 


AND NEW RESILIENT CHANNELS --t-~::::::::::~-

EXISTING STRAPPING TO REMAIN 

NEW SPRAY FOAM INSULATION 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

TYPICAL FLOOR ASSEMBLY BETWEEN UNITS -STEP 3 

SCALE: 1112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W1a-3 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 114

NEW (3) 2" LAYERS OF DOW XPS RIGID 


INSULATION, JOINTS OFFSET AND 


TAPED, OUTER LAYER AS AIR BARRIER 


NEW%" TYPE X GYPSUM BOARD 


NEW 2x4 WOOD STUD@ 16" O.C. 


NEW SPRAY FOAM INSULATION 


NEW STRIP OF MOLD RESISTANT 


FIRE RATED GYPSUM BOARD 


NEW CONTINUOUS BEAD OF SEALANT 


EXISTING OR NEW WOOD 


FLOORING 


EXISTING WOOD SUBFLOOR CUT 


AWAY 6 X" FROM THE WALL 

EXISTING OR NEW 


WOOD FLOOR JOIST 


NEW STRIPS OF MOLD RESISTANT FIRE 

THICKNESS TO EXISTING STRAPPING 


AND NEW RESILIENT CHANNELS 


RATED GYPSUM BOARD, MATCH --i~~~~~~@~~~~~~~~(:j 

NEW FIBERGLASS BATI 


INSULATION, MIN. 3" 


EXISTING STRAPPING TO REMAIN 


NEW RESILIENT CHANNELS@ 24" O.C. 


NEW%" TYPE X GYPSUM BOARD 


NEW TAPED JOINT, TYPICAL BOTH SIDES 


NEW CONTINUOUS BEAD OF SEALANT 


NEW SPRAY FOAM INSULATION 


CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

TYPICAL FLOOR ASSEMBLY BETWEEN UNITS -STEP 4 

SCALE: 1 112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W1a-4 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 115

NEW (3) 2" LAYERS OF DOW XPS RIGID 

INSULATION, JOINTS OFFSET AND 

TAPED, OUTER LAYER AS AIR BARRIER --t------------1--­

EXISTING OR NEW WOOD FLOORING 

EXISTING WOOD SUBFLOOR CUT 


AWAY 6 ~" FROM THE WALL 


EXISTING OR NEW 

WOOD FLOOR JOIST --~====:::::S~=====~=I 

EXISTING STRAPPING TO REMAIN 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

TYPICAL FLOOR ASSEMBLY BETWEEN UNITS -STEP 1 

SCALE: 1112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W1b-1 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 116

NEW (3) 2" LAYERS OF DOW XPS RIGID 

INSULATION, JOINTS OFFSET AND 

TAPED, OUTER LAYER AS AIR BARRIER --+-----------+ 

EXISTING OR NEW WOOD FLOORING 

EXISTING WOOD SUBFLOOR CUT 


AWAY 6)/2" FROM THE WALL 


EXISTING OR NEW 


WOOD FLOOR JOIST --{::;;=====:;;;;====~==::::::Ji:~~~ =~ 

EXISTING STRAPPING TO REMAIN 

NEW STRIPS OF MOLD RESISTANT FIRE 

RATED GYPSUM BOARD, MATCH 

THICKNESS TO EXISTING STRAPPING 

AND NEW RESILIENT CHANNELS 

NEW SPRAY FOAM INSULATION 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

TYPICAL FLOOR ASSEMBLY BETWEEN UNITS -STEP 2 

SCALE: 1112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W1b-2 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 117

NEW {3) 2" LAYERS OF DOW XPS RIGID 

INSULATION, JOINTS OFFSET AND 

TAPED, OUTER LAYER AS AIR BARRIER 

NEW SPRAY FOAM INSULATION 

NEW STRIP OF MOLD RESISTANT 


FIRE RATED GYPSUM BOARD, 


CUT DOWN SPRAY FOAM TO 


ACCOMMODATE GYPSUM BOARD 


EXISTING OR NEW WOOD FLOORING 

EXISTING WOOD SUBFLOOR CUT 


AWAY 6 '/z" FROM THE WALL 


EXISTING OR NEW 

WOOD FLOOR JOIST -~rs;:~~~~==j ~~i~~=~ 

EXISTING STRAPPING TO REMAIN 

NEW STRIPS OF MOLD RESISTANT FIRE 

RATED GYPSUM BOARD, MATCH 

THICKNESS TO EXISTING STRAPPING 

AND NEW RESILIENT CHANNELS 

NEW SPRAY FOAM INSULATION 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

TYPICAL FLOOR ASSEMBLY BETWEEN UNITS -STEP 3 

SCALE: 1 112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W1b-3 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 118

NEW (3) 2" LAYERS OF DOW XPS RIGID 

INSULATION, JOINTS OFFSET AND 

TAPED, OUTER LAYER AS AIR BARRIER 

NEW%" TYPE X GYPSUM BOARD 

NEW 2x4 WOOD STUD@ 16" O.C. 

NEW SPRAY FOAM INSULATION 

NEW STRIP OF MOLD RESISTANT 


FIRE RATED GYPSUM BOARD, 


CUT DOWN SPRAY FOAM TO 


ACCOMMODATE GYPSUM BOARD 


NEW CONTINUOUS BEAD OF SEALANT 

EXISTING OR NEW WOOD 


FLOORING 


EXISTING WOOD SUBFLOOR CUT 


AWAY 6 ~· FROM THE WALL 


EXISTING OR NEW 

wooD FLooR JoisT --rs~~~~===Ijj~ffi~~::j 

NEW FIBERGLASS BATI 


INSULATION, MIN. 3" 


EXISTING STRAPPING TO REMAIN 


NEW RESILIENT CHANNELS @ 24" O.C. 


NEW%" TYPE X GYPSUM BOARD 


NEW TAPED JOINT, TYPICAL BOTH SIDES 


NEW CONTINUOUS BEAD OF SEALANT 


NEW STRIPS OF MOLD RESISTANT FIRE 


RATED GYPSUM BOARD, MATCH 


THICKNESS TO EXISTING STRAPPING 


AND NEW RESILIENT CHANNELS 


NEW SPRAY FOAM INSULATION 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

TYPICAL FLOOR ASSEMBLY BETWEEN UNITS -STEP 4 

SCALE: 1 112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W1b-4 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 119

NEW%" TYPE X GYPSUM BOARD 

NEW TAPED JOINT, 


TYPICAL BOTH SIDES 


NEW STRIP OF X" PLYWOOD FOR 

ATTACHING GYPSUM BOARD 

NEW%" TYPE X GYPSUM BOARD 

NEW 2x4 WOOD STUD@ 16" O.C. --1------1 

NEW TAPE AT EACH JOINT ---J::--r~~~........,.........,.~~~~~--=;;=,~~_._,~~~~~~~r--TI 

NEW (3} 2" LAYERS OF DOW XPS 


RIGID INSULATION, JOINTS 


OFFSET AND TAPED, OUTER 


LAYER AS AIR BARRIER -~"'

NEW DOW INSTA STIK 


POLYURETHANE ADHESIVE 


EXISTING BRICK TO BE 


REPAIRED AND REPOINTED 


CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

WALL- TYPICAL INTERIOR PARTITION - PLAN 


SCALE: 1112" =1'·0" 

Merrimack Valley Habitat for Humanity 

Wall Details 

Date: 2012-02-06 

Sheet Title: 

W2 
 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 120

NEW (2) LAYERS OF%" TYPE X 


GYPSUM BOARD SCREWED 12" O.C. 


NEW RESILIENT CHANNELS 


24" O.C., ONE SIDE 


NEW (2) LAYERS OF%" TYPE X 


GYPSUM BOARD SCREWED AT EDGES 


AND AT CENTER 12" O.C. (BOTH SIDES 


WATER RESISTANT AT WET AREAS) 

NEW TAPED JOINT, 


TYPICAL BOTH SIDES --~ 

NEW;{,"TYPEXGYPSUMBOARD --~ 

NEW STRIPS OF MOLD RESISTANT FIRE 

RATED GYPSUM BOARD, MATCH 

THICKNESS TO NEW GYPSUM BOARD 

AND RESILIENT CHANNELS --+-------------1-wt~l 

NEW2x4 NEW (3) 2" WOOD LAYERS STUD@ OF DOW 16" O.C. XPS 
--l ~~~~=~~m~~ m--~ ~~~~~~::J:d RIGID INSULATION, JOINTS 


OFFSET AND TAPED, OUTER 


LAYER AS AIR BARRIER, STEP 


LAYERS AWAY FROM GWB TO 


ALLOW FOR SPRAY FOAM SEAL 

NEW TAPE AT EACH JOINT 

NEW DOW INSTA STIK 


POLYURETHANE ADHESIVE 


2" MINERAL FIBER INSULATION 


TO PROVIDE THERMAL BREAK 


AT EXTERIOR 


NEW SPRAY FOAM SEAL 


BETWEEN INSULATING 


SHEATHING AND GWB 


EXISTING BRICK TO BE 


REPAIRED AND REPOINTED 


CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

WALL- TYPICAL DEMISING PARTITION - PLAN 

SCALE: 1112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W3 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 121

NEW 2x4 WOOD STUD@ 16" O.C. 

NEW WOOD BASE 

NEW 3~" SOUND ATTENUATION BLANKET 

NEW2x4 BOTTOM PLATE 


NEW CONTINUOUS FILLET 


SEALANT BEAD, SEAL GWB TO TOP 


OF DECK, TYPICAL BOTH SIDES 


EXISTING OR NEW WOOD 


FLOORING 


EXISTING WOOD SUBFLOOR 


NEW CONTINUOUS FIRE RATED 


SEALANT BEAD OR EXPANDING 


FOAM, SEAL GWB TO UNDERSIDE 


OF DECK, TYPICAL BOTH SIDES ---.­

NEW (2) 2x4 TOP PLATES _ ____....­


NEW RESILIENT CHANNELS 


24" O.C., ONE SIDE 


MIN. 3" FIBERGLASS INSULATION 


EXISTING OR NEW WOOD FLOOR JOIST 


EXISTING STRAPPING TO REMAIN 


NEW RESILIENT CHANNEL@ 24" O.C. 


NEW%" TYPE X GYPSUM BOARD 


NEW TAPED JOINT, TYPICAL BOTH SIDES 


NEW WOOD BLOCKING FOR 


GYPSUM BOARD ATTACHMENT, 


TYPICAL BOTH SIDES 


NEW (2) LAYERS OF%" TYPE X 

GYPSUM BOARD SCREWED 12" O.C. 


NEW (2) LAYERS OF%" TYPE X 


GYPSUM BOARD SCREWED AT EDGES 


AND AT CENTER 12" O.C. (BOTH SIDES 


WATER RESISTANT AT WET AREAS) CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

WALL- TYPICAL DEMISING PARTITION -SECTION 1 

SCALE: 3" =1'o{)" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W4 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 122

EXISTING OR NEW WOOD FLOORING 

NEW WOOD BLOCKING FOR 


GYPSUM BOARD ATIACHMENT 


EXISTING WOOD SUBFLOOR ---J;;;:::;;;;;;;::::::::::s;;:::;:;;;:::======~=============l 

EXISTING OR NEW 


WOOD FLOOR JOIST --t------r~t 

NEW CONTINUOUS FIRE 


RATED EXPANDING FOAM, 


SEAL GWB TO UNDERSIDE OF 


DECK AND FLOOR JOISTS 


NEW DOUBLE 2x4 WOOD TOP PLATE ------""-~:;::-------------------------1 

NEW %" TYPE X GYPSUM 

BOARD, NOTCH AROUND 

JOISTS OR PATCH IN --+------­

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

WALL- TYPICAL DEMISING PARTITION -SECTION 2 


SCALE: 3" =1'.{1" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W5 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 123

EXISTING OR NEW WOOD 


FLOORING 


EXISTING WOOD SUBFLOOR --1==:::;::;;==~~========================================1 

EXISTING OR NEW WOOD 


FLOOR JOIST --+------1 


EXISTING STRAPPING TO REMAIN 

NEW RESILIENT CHANNELS 24" O.C. 


NEW%" TYPE X GYPSUM BOARD 


NEW TAPED JOINT, TYPICAL BOTH SIDES 


NEW GYPSUM BOARD GASKET, 


TYPICAL BOTH SIDES 


NEW (2) 2x4 TOP PLATES 


NEW 2x4 WOOD STUD@ 16" O.C. 

NEW 2 LAYERS OF%" TYPE X 


GYPSUM BOARD 


CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

WALL- TYPICAL INTERIOR PARTITION -SECTION 3 

SCALE: 3" =1'o{)" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W6 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 124

NEW%" TYPE X GYPSUM BOARD 

NEW GYPSUM BOARD GASKET, 

TYPICAL BOTH SIDES 

NEW TAPED JOINT, TYPICAL BOTH SIDES 

NEW STRIP OF]!!" PLYWOOD FOR 

ATTACHING GYPSUM BOARD 

NEW (2) LAYERS OF%" TYPE X 

GYPSUM BOARD SCREWED 12" O.C. 

NEW LOW-EXPANSION SPRAY FOAM 

FOR AIR BARRIER CONTINUITY, 

TYPICAL BOTH SIDES _ _........,... 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

WALL- TYPICAL INTERIOR TO DEMISING PARTITION - PLAN 


SCALE: 3" =1'.{1" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Wall Details 

Date: 2012-02-06 W7 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 125

Air Barrier Strategy 

Goals and principles of air barriers and compartmentalization 

• 	 Each unit should be airtight as possible to the outside 

• 	 Each unit should be isolated/airtight from another rcompartrnentalization") 

• 	 Each unit should be isolated/airtight from the corridor (•compartmentalization•) 

• 	 We are designating an airtight plane on •au six sides of the cube• (each unit) 

o 	 Each plane needs to be made airtight as possible: it must be made of an airtight material, and penetrations through 

the air barrier layer must be sealed to the air barrier 

o 	 Each plane needs to be connected to the adjacent plane in an airtight manner 

Exterior wall air barrier (inside-to-outside) 

• The XPS (extruded polystyrene) rigid foam insulation forms the air barrier at the exterior walls; the seams are taped at the 

outermost and innermost layers. 

• Closed-cell spray foam is used to connect the XPS at difficult transitions (to window opening, portions of uneven surface 


brick, and the joist/floor areas (see sequence Details W1 a and W1 b). 


• 	 Windows and doors must be connected to the air barrier layer (see Details WS, WH, WJ) 

Demising wall air barrier (unit-to-unit and unit-to-corridor} 

• 	 The surface of the gypsum board is the air barrier layer, on each side of the demising wall 

• 	 All penetrations through the gypsum board must be made airtight: 

o 	 Electrical boxes should be airtight boxes, or alternately, caulked/sealed boxes 

o 	 All mechanical and plumbing penetrations must be sealed to the gypsum board, where they penetrate through, on 

each side of the drywall 

o 	 Door frames to each unit should be sealed to the gypsum board with low-expansion spray foam (Detail W7) 

• 	 Connections to the exterior wall as per Detail W3 (spray foam connection to XPS) 

• 	 Connections to the floor and ceiling air barrier to be done with caulk, sealant, or gaskets (Details W4, W5) 

• 	 Where the interior wall meets the demising wall, the air barrier must be •passed" through the framing (Detail W7) 

Ceiling (gypsum board side) air barrier 

• Where the ceiling gypsum board is interrupted by partition wall framing, the air barrier must be •passed" through the 


framing (Detail W6) 


• 	 Any soffits must be built with the gypsum (or other air barrier) continuous behind the soffit (Detail A 1) 

• 	 All penetrations through the gypsum board must be made airtight: 

o 	 Electrical boxes should be airtight boxes, or alternately, caulked/sealed boxes (Detail A3) 

o 	 All mechanical and plumbing penetrations must be sealed to the gypsum board, where they penetrate through, on 

each side of the drywall (Detail A3) 

o 	 Attic hatch must be made airtight (Detail A2) 

Floor (flooring side} air barrier 

• 	 All penetrations through the subfloor must be sealed (e.g., plumbing and wiring penetrations) (Detail A3) 

AIR BARRIER STRATEGY 

NOT TO SCALE 

Merrimack Valley Habitat for Humanity Sheet Title: 

Air Sealing Details 

Date: 2012-02-06 ABS COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 126

Solid blocking as draftstop (seams/ 

joints sealed with adhesive or sealant) 

Sealant, adhesive Sealant, adhesive 

or gasket or gasket 

Sealant or adhesive --~+------' Sealant or adhesive 

f--r--­.---l 

Dropped ceiling 

framing 

DROPPED CEILING 

Sealant, adhesive 

or gasket 

Soffit and soffit gypsum board 

installed after primary gypsum 

board installation 

Gypsum board joint taped/sealed 

prior to soffit construction 

INTERIOR SOFFIT INSTALLED 

AFTER GYPSUM BOARD INSTALLED 

INTERIOR SOFFIT AND DROPPED CEILING AIR SEALING 


NOT TO SCALE 

Merrimack Valley Habitat for Humanity Sheet Title: 

Air Sealing Details 

Date: 2012-02-06 A1 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 127

Insulation pillow 

(cut batt insulation slightly 

oversize and place in 

plastic bag creating a 

"pillow") Insulation dam 

Gasket/weatherstrip J

~asing trim installed 

attached to door over gypsum board 

Removable screws 

holding door in place 

ATTIC ACCESS OR REMOVABLE COVER 

Insulation pillow 

(cut batt insulation slightly 

oversize and place in Gasket/weatherstrip plastic bag creating a attached to door "pillow") 

Sealant, adhesive Casing/trim installed 

or gasket over gypsum board 

ATTIC ACCESS VIA SCUTTLEHOLE 

ATTIC ACCESS AIR SEALING 

NOT TO SCALE 

Merrimack Valley Habitat for Humanity Sheet Title: 

Air Sealing Details 

Date: 2012-02-06 A2 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 128

Flange for sealing Built-In seal at to drywall air barrier 

wire entrance ~ 

Caulk/seal/foam all electrical wires penetrating into "' Gasket built Into box 

attic spaces or insulated ceiling 

- Special air-sealing box 

Interior 

wall 

Caulk/seal/ 

foam all 

electrical 

wires 

penetrating 

top and 

bottom 

plates of 

exterior 

walls 

Run 

wiring 

along 

side of 

stud at 

exterior 

wall 

Run 

wiring 

along 

bottom 

Exterioir 

wall 

Caulk at all wire penetrations 

Seal at face to drywall with joint 

compound or with caulked foam 

cover plate gasket 

Standard plastic electrical box 

Caulk/seal/foam all electrical 

wires penetrating into exterior 

wall Caulk at all openings 

SEALING ELECTRICAL WIRES ELECTRICAL BOXES 

AT DEMISING WALLS 

ELECTRICAL WIRES AND BOXES AIR SEALING 

NOT TO SCALE 

Merrimack Valley Habitat for Humanity Sheet Title: 

Air Sealing Details 

Date: 2012-02-06 A3 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 129

NEW 3 J1!" CLOSED-CELL (2.0 pcf) 


SPRAY FOAM INSULATION 


NEW 2x4 WOOD STUD@ 16" O.C. 


NEW%" TYPE X GYPSUM BOARD 


NEW -6" STRIP OF 2" DOW XPS 


RIGID INSULATION 


NEW SILL SEAL UNDER BOTTOM 

PLATE FOR CAPILLARY BREAK _ __.....­

NEW 4" CONCRETE SLAB ------rr 

NEW 6 MIL POLYETHYLENE VAPOR 


BARRIER, TURN UP EDGE OF SLAB -~-c:: 

NEW 2" LAYER OF DOW XPS 

RIGID INSULATION 

NEW 3 J1!" PERFORATED DRAIN PIPE 

NEW 4" GRAVEL AND FILL PAD 

COMPACTED AS REQUIRED 

EXISTING CONCRETE SLAB 

BASEMENT SLAB AND WALL 1 

SCALE: 1 112" =1'·0" 

Merrimack Valley Habitat for Humanity 

Basement Details 

Date: 2012-06-26 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

Sheet Title: 

81 
 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 130

NEW 3 ~· CLOSED-CELL (2.0 pcf) 


SPRAY FOAM INSULATION 


NEW 2x4 WOOD STUD@ 16" O.C. 

NEW%" TYPE X GYPSUM BOARD 

NEW -6" STRIP OF 2" DOW XPS 


RIGID INSULATION 


NEW SILL SEAL UNDER BOTTOM 


PLATE FOR CAPILLARY BREAK _ __......­

NEW 6 MIL POLYETHYLENE VAPOR 


BARRIER, TURN UP EDGE OF SLAB _ _....,.,­

NEW 2" LAYER OF DOW XPS 


RIGID INSULATION 


NEW COSELLA DORKEN DEL TA-FL 


DIMPLE MAT, TURN UP THE WALL 


MIN. 6", ALL SEAMS TAPED 


EXISTING CONCRETE SLAB 
 ' I 
 I ------= I 

BASEMENT SLAB AND WALL 2 

SCALE: 1 112" =1'·0" 

Merrimack Valley Habitat for Humanity 

Basement Details 

Date: 2012-06-26 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

Sheet Title: 

82 
 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 131

NEW%" TYPE X GYPSUM BOARD 

NEW 4" CONCRETE SLAB 

NEW CONTINUOUS BEAD 


OF URETHANE SEALANT 


NEW WOOD BLOCKING 

NEW 6 MIL POLYETHYLENE 


VAPOR BARRIER --~ 

NEW 2" LAYER OF DOW XPS 


RIGID INSULATION --­

NEW 3X" PERFORATED DRAIN PIPE --­

NEW WOOD BLOCKING ---­

NEW 2" LAYER OF DOW XPS, ~~L,....------LL--.........._____1 II
 RIGID INSULATION, 


JOINTS OFFSET AND TAPED 


NEW CONTINUOUS BEAD 


OF URETHANE SEALANT 
 >=====:~~11 111 11 EXISTING CONCRETE SLAB 

NEWX" CEMENT BACKER BOARD --'""' 

~11111 NEW 2" LAYER 

RIGID 

OF 

INSULATION 

DOW XPS 


__...,.­ 11 NEW INSTASTIK SEALANT, APPLY AT 


PERIMETER OF RIGID INSULATION _ __...., 


~IIIIII 

NEW EPOXY PAINT COATING FOR 


VAPOR DIFFUSION CONTROL, OR 


ALTERNATE TOPPING SLAB WITH 


6 MIL POLYETHYLENE VAPOR 


BARRIER UNDERNEATH 
 ==-1111111 IIIII 

NEW CONTINUOUS BEAD OF SEALANT 

EXISTING CONCRETE SLAB 

l_ 

1 11,11111111111111111111111­ l __, , , __lll 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

BASEMENT SLAB AND WALL 3 

SCALE: 1 112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Basement Details 

Date: 2012-06-26 83 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 132

EXISTING OR NEW WOOD 

FLOORING 

EXISTING WOOD SUBFLOOR 

EXISTING OR NEW WOOD 

FLOOR JOIST --+------------------fi 

EXISTING STRAPPING TO REMAIN 

NEW RESILIENT CHANNELS 24" O.C. 

NEW%" TYPE X GYPSUM BOARD 

FINISHED FLOORING 

NEW 4" CONCRETE SLAB 

NEW 6 MIL POLYETHYLENE 


VAPOR BARRIER 


NEW COSELLA DORKEN 

DELTA-FL DIMPLE MAT, ~~""'i""T=rrr==!- Ill Ill 

ALL SEAMS TAPED 

-11111111111111111111111111' 

CJ 

GRAY TONE INDICATES 

EXISTING STRUCTURE 

BASEMENT EXISTING AND NEW SLAB CONNECTION 


SCALE: 1 112" =1'·0" 

Merrimack Valley Habitat for Humanity Sheet Title: 

Basement Details 

Date: 2012-06-26 84 COPYRIGHT @ 2012 BUILDING SCIENCE CORPORATlON 
 133

~+--- Vent stack 

I Concrete slab 

Polyethylene vapor 

barrier 

Sealant at all slab 

penetrations Granular drainage 

pad (no fines) 

Perforated drain pipe added 

to 'Tin order to couple sub· 

slab pressure field to vent stack 

SOIL GAS VENT 

SCALE; 1 1/2' = 1'·0' 

Merrimack Valley Habitat for Humanity Sheet Title: 

Basement Details 

~-· U.S. Department Df Energy 

,__,.~z.oEMIJIYHtNrr. Date: 2012-06-26 85

COPYRIGHT@) 2012 BUILDING SCIENCE CORPORATION 
134 

Appendix C: MVHfH REM/Rate Energy Modeling Results
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ENERGY STAR VERSION 2 HOME VERIFICATION SUMMARY
�

Date: October 29, 2012 Rating No.: 

Building Name: MV Habitat Convent Rating Org.: Advanced Building Analysis LLC 

Owner's Name: U=0.49 SHGC=0.60 Phone No.: (978) 270-3911 

Property: 100 Parker Street Rater's Name: Michael A. Browne 

Address: Lawrence, MA 01843 Rater's No.: 3992602 

Builder's Name: MV Habitat for Humanity 

Weather Site: Lawrence, MA Rating Type: Based On Plans 

File Name: Convent Unit 2 - Design Spec.blg Rating Date: 12/7/2011 

Building Information 

Conditioned Area (sq ft): 1398 Housing Type: Apartment, end unit 

Conditioned Volume (cubic ft): 12972 Foundation Type: Conditioned basement 

Insulated Shell Area (sq ft): 2841 HERS Index: 63 *****+ 

Number of Bedrooms: 3 

Building Shell 

Ceiling w/Attic: None Window/Wall Ratio: 0.19 

Vaulted Ceiling: None Window Type: U:0.30, SHGC:0.30 

Above Grade Walls: R39,FG1,4-16,D U=0.031 Window U-Value: 0.300 

Found. Walls (Cond): MV Hab Convent Fnd R=20.0 Window SHGC: 0.300 

Found. Walls (Uncond): None Infiltration: Htg: 2.00 Clg: 2.00 ACH50 

Frame Floors: None Duct Leakage to Outside: NA 

Slab Floors: R10P,R10U,24W U=0.044 Total Duct Leakage: NA 

Mechanical Systems 

Heating: Fuel-fired hydronic distribution, 136.5 kBtuh, 91.0 % EFF.
�

Water Heating: Instant water heater, Gas, 0.91 EF.
�

Programmable Thermostat: Heat=No; Cool=No
�

Note: Where feature level varies in home, the dominant value is shown.
�

This home MEETS OR EXCEEDS the EPA's requirements for an ENERGY STAR Home. 

REM/Rate - Residential Energy Analysis and Rating Software v12.96 

This information does not constitute any warranty of energy cost or savings. 

© 1985-2011 Architectural Energy Corporation, Boulder, Colorado. 

135
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ENERGY STAR VERSION 2 HOME VERIFICATION SUMMARY
�

Date: October 29, 2012 Rating No.: 

Building Name: MV Habitat Convent Rating Org.: Advanced Building Analysis LLC 

Owner's Name: U=0.49 SHGC=0.60 Phone No.: (978) 270-3911 

Property: 100 Parker Street Rater's Name: Michael A. Browne 

Address: Lawrence, MA 01843 Rater's No.: 3992602 

Builder's Name: MV Habitat for Humanity 

Weather Site: Lawrence, MA Rating Type: Based On Plans 

File Name: Convent Unit 3 - Design Spec.blg Rating Date: 12/8/2011 

Building Information 

Conditioned Area (sq ft): 940 Housing Type: Apartment, end unit 

Conditioned Volume (cubic ft): 9971 Foundation Type: Apartment above conditioned space 

Insulated Shell Area (sq ft): 1112 HERS Index: 60 *****+ 

Number of Bedrooms: 3 

Building Shell 

Ceiling w/Attic: None Window/Wall Ratio: 0.27 

Vaulted Ceiling: None Window Type: U:0.30, SHGC:0.30 

Above Grade Walls: MV Hab Convent R30I U=0.029 Window U-Value: 0.300 

Found. Walls (Cond): None Window SHGC: 0.300 

Found. Walls (Uncond): None Infiltration: Htg: 2.00 Clg: 2.00 ACH50 

Frame Floors: None Duct Leakage to Outside: NA 

Slab Floors: None Total Duct Leakage: NA 

Mechanical Systems 

Heating: Fuel-fired hydronic distribution, 136.5 kBtuh, 91.0 % EFF.
�

Water Heating: Instant water heater, Gas, 0.91 EF.
�

Programmable Thermostat: Heat=No; Cool=No
�

Note: Where feature level varies in home, the dominant value is shown.
�

This home MEETS OR EXCEEDS the EPA's requirements for an ENERGY STAR Home. 

REM/Rate - Residential Energy Analysis and Rating Software v12.96 

This information does not constitute any warranty of energy cost or savings. 

© 1985-2011 Architectural Energy Corporation, Boulder, Colorado. 

136
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ENERGY STAR VERSION 2 HOME VERIFICATION SUMMARY
�

Date: October 29, 2012 Rating No.: 

Building Name: MV Habitat Convent Rating Org.: Advanced Building Analysis LLC 

Owner's Name: U=0.49 SHGC=0.60 Phone No.: (978) 270-3911 

Property: 100 Parker Street Rater's Name: Michael A. Browne 

Address: Lawrence, MA 01843 Rater's No.: 3992602 

Builder's Name: MV Habitat for Humanity 

Weather Site: Lawrence, MA Rating Type: Based On Plans 

File Name: Convent Unit 8 - Design Spec.blg Rating Date: 12/8/2011 

Building Information 

Conditioned Area (sq ft): 1384 Housing Type: Apartment, end unit 

Conditioned Volume (cubic ft): 12444 Foundation Type: Apartment above conditioned space 

Insulated Shell Area (sq ft): 2736 HERS Index: 48 *****+ 

Number of Bedrooms: 3 

Building Shell 

Ceiling w/Attic: None Window/Wall Ratio: 0.12 

Vaulted Ceiling: MV Habi Convent Flat U=0.016 Window Type: U:0.30, SHGC:0.30 

Above Grade Walls: MV Hab Convent R30I U=0.029 Window U-Value: 0.300 

Found. Walls (Cond): None Window SHGC: 0.300 

Found. Walls (Uncond): None Infiltration: Htg: 2.00 Clg: 2.00 ACH50 

Frame Floors: None Duct Leakage to Outside: NA 

Slab Floors: None Total Duct Leakage: NA 

Mechanical Systems 

Heating: Fuel-fired hydronic distribution, 136.5 kBtuh, 91.0 % EFF.
�

Water Heating: Instant water heater, Gas, 0.91 EF.
�

Programmable Thermostat: Heat=No; Cool=No
�

Note: Where feature level varies in home, the dominant value is shown.
�

This home MEETS OR EXCEEDS the EPA's requirements for an ENERGY STAR Home. 

REM/Rate - Residential Energy Analysis and Rating Software v12.96 

This information does not constitute any warranty of energy cost or savings. 

© 1985-2011 Architectural Energy Corporation, Boulder, Colorado. 

137
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ENERGY STAR VERSION 2 HOME VERIFICATION SUMMARY
�

Date: October 29, 2012 Rating No.: 

Building Name: MV Habitat Convent Rating Org.: Advanced Building Analysis LLC 

Owner's Name: U=0.49 SHGC=0.60 Phone No.: (978) 270-3911 

Property: 100 Parker Street Rater's Name: Michael A. Browne 

Address: Lawrence, MA 01843 Rater's No.: 3992602 

Builder's Name: MV Habitat for Humanity 

Weather Site: Lawrence, MA Rating Type: Based On Plans 

File Name: Convent Unit 9 - Design Spec.blg Rating Date: 8/31/2011 

Building Information 

Conditioned Area (sq ft): 1127 Housing Type: Apartment, end unit 

Conditioned Volume (cubic ft): 12084 Foundation Type: Apartment above conditioned space 

Insulated Shell Area (sq ft): 2443 HERS Index: 53 *****+ 

Number of Bedrooms: 3 

Building Shell 

Ceiling w/Attic: None Window/Wall Ratio: 0.13 

Vaulted Ceiling: MVH Convent Cath U=0.034 Window Type: U:0.30, SHGC:0.30 

Above Grade Walls: MV Hab Convent R30I U=0.029 Window U-Value: 0.300 

Found. Walls (Cond): None Window SHGC: 0.300 

Found. Walls (Uncond): None Infiltration: Htg: 2.00 Clg: 2.00 ACH50 

Frame Floors: None Duct Leakage to Outside: NA 

Slab Floors: None Total Duct Leakage: NA 

Mechanical Systems 

Heating: Fuel-fired hydronic distribution, 136.5 kBtuh, 91.0 % EFF.
�

Water Heating: Instant water heater, Gas, 0.91 EF.
�

Programmable Thermostat: Heat=No; Cool=No
�

Note: Where feature level varies in home, the dominant value is shown.
�

This home MEETS OR EXCEEDS the EPA's requirements for an ENERGY STAR Home. 

REM/Rate - Residential Energy Analysis and Rating Software v12.96 

This information does not constitute any warranty of energy cost or savings. 

© 1985-2011 Architectural Energy Corporation, Boulder, Colorado. 

138
139 

Appendix D: MVHfH Mechanical Design
BUILDING SCIENCE 

CORPORATION 

EQUIPMEN! SPfiQIF!Cr\IIQN§ IFORCE:Q HQI WATER Sl'SJ'EMl 
 EgUIPMENTSPECIFICA.TIONB SYSTEM}
 

INSTAI.l.ATION NOTES' 

1.1NSTALL BOILERS, CONFIGURE BOILERCON1'ROL8 RNNED TUBE RADio\TION (FIR) APARTMENT HEAT RECOVERYVENTILATOR (HRV) HRV·1 

AND START-l-IP BOILERS IN S'IRICT ACCORDANCE SMITHS ENVIRONMENTAL HEATINCl EDClE HE2 BASEBOARD 

FANTECH FLEX 100H 

wmi BOILER MANUFACTURER INS'1RUC'110NS. 689 BTUMRIFT G 12DDECl F EWT 

ALUMINUM HEAT RECOVERY CORE 

2 EBM MOTORS WITH RADIAL CURVED BlADES 

TWO SUPPUES PARALLEL PIPE CONRGURATION 

2. THE R..OOR OF EACH MECHANICAL CLOSET SHALL 314" COPPER TUBE/ALUMINUM AN INTERNAL RECIRCUlATION DEFROST 

BE FIT'TED WITH A FULL SIZE DRIP PAN WITH PLUMIII:D 2 WASHABLE ELECTROSTATIC AIR FILTERS 

DRAIN. PAN SHALL BE MIN ElCPANSION TANK ET·1 (APARTMENTS) 0.0218" THICK GALVANIZED 


STEEL.IJ.032"THICKAI.UMINUM ORD.CII26" THICK 


WATTS REGUlATOR MOOEL ET-15 COMMON AREA HEAT RECOVERY YEI'ITILATOR (HRV) HRV-2 NON·POTABLEWATER.IIO PSIGCWP 

MINIMUM ACCEPTANCE VOLUME= 1.0 GALLONS 

PLASTIC. HClT SHALL BE MIN 1·1/Z" WITH ROiilD EDGE. FANTECH VHR 2!105R 

ALUMINUM HEAT RECOVERY CORE 30 FOREST STREET SOMERVILLE, MA 

3. PROVIDE FL.EXIIL.E PIPE CONNECTORS AT PUMPS. 71 2 EBM MOTORS WITH RADIAL CURVED BlADES T: (978) 589-5100 F: (978) 589-5103 

ElCPANSION TANK ET-2 (COMMON AREAS) 

WATTS INTERNAL RECIRCUlATION DEFROST 

4. ADJUST CALIBRATED SAI.ANCINCl VALVES AT REGUlATOR MOOEL www.buildingscience.com 2 WASHABLE ELECTROSTATIC AIR FILTERS 

EACH PUMP TO OBTAIN INDICATED FLOW RATE. NON-POTABLE WATER. 110 PSIG CWP

MINIMUM ACCEPTANCE VOLUME= 2.5GAI.LONS MEETING ROOM EXHAUST FAN El!-1 

5. HEATlRANSFER FLUID IS PlAIN WATER (NO ClLYCOI..). AIR SEPARATOR MR. WHISPER (SUPPLIED BY HABITAT) CONSULTANT' 

WATTS REClULATOR MOOELAS-r.e, 1" SIZE 

6. FL.EXIIL.E DUCT SHALL NOT BE PERMIT'TED. ICJTCHEN HOOD 1<11-1 

BROAN MODEL QSE1 SERIES, ALLURE- ENERGY STAR RATED ALITOMATIC AIR VENT 


WATTS REClULATOR "DUOVENT' 


1. SEALAIJ. DUCTWORK SMOKE·TIGHT. 2-$PEED, If' DUCT 

INT1EGRATED BACKDRAFT DAIFER 

8. PROVIDE DUCT ACCESS DOOR EVERY 25 FEET IN PRESSURE REDUCINCl VALYE!BACKFLOW PREYENTlER 1-411 CFMATNORMALSPEED

FRESH AIR DUCTS AND BATHROOM EXHAUST DUCTS. WATTS 911S COMBINATION FILL VALYEAW:KFLOWPREYENTER 2211 CFM AT MAXIMUM SPEEDDUCT ACCESS DOORS SHALL BE MINIMUM If' X If'. 1.11AMPS, 12011A!KJ 

9. INSUlATE ALL FRESH AIR DUCTWORK QNa.uDING TEMPERATURE!PRESSURE ClAIJClE 

WATTS MODEL 105100 
 KITCHEN EXHAUST SYSTEMS

FRESH AIR DUCTWORK IN SPACES ABOVE CEILINGS) TO 60 TO :!!20 DEG F, 0 TO 200 PSI 
 ClREENHECK ClREENYENT SYS'TEM


 INSULATE AIJ. HOT AND COlD WATER PIPING. AIJ.aN VARH3REEN CONSTANT PRESSURE CONTROl. 

MIN 2"CLEARANCE BETWEEN INSULATED PIPING, 

MANIFOLO 
 MODEL CUE-c&O-VG EXHAUST FAN, DIRECT DRIVE UPBIAST

 
 INSULATIED DUCTWORK, AND OTHER BUILDING COM­ WATTS FLOWMETER MANIFOLO 
 WITH GPI ROOF CURB

PONENTS. STAINLESS STEEL. 1" WITH TRUNK ISO ICIT STACK 1 • 400 CAM, STACKB 2 &3 • 300 CFM EACH ., 

HP, 120111110 .. 10. BOILER FLUE PIPING SHALL NOT EXCEED 100 FEET 

BOILERS B-1 (APARTMENTS AND COMMON AREA) 

EQUIYAI.EI'IT STRAIGHT LENGTH PER BOILER. BOILER NAVIEN MODEL Cli-180 
 SUBDUCT RISER

E 
 COMBUSTION AIR PIPINCl SHALL NOT EXCEED 100 FEET NAT. MODULATING CONDENSING EXHAUSTO SDR 08

H EQUIYAI.EI'IT STRAIClHT LENGTH PER BOILER. 110 OECl 8" DUCT CONNEC'110N ELBOW• 6 FEET, 46 DECl EUIOW•3 FEET, CON-	 COMBINATION WATERHEA'TERotiOILER 

26GAUGE GALVANIZED STlEEL CENTRIC VENT KIT • 3 FEET. HORIZONTAL BOILER 150 MBH MAX/ 17 MIIH MIN INPUT, 


FLUE PIPING SHALL PITCH UP 114 INCH PEA FOOT 120 DEO F 100 DEG F HWR, 5 OPM 


HRY ROOF TERMINATION AWAY FRCW BOILER. SUPPORT BOILER FLUE AND 120 DEG F DOMESTIC HOT WATER" AMERICAN ALOES MODEL RCR 22 438 COMBUSTION AIR PIPING 5 FEET ON CENTlER. 	 "CONTROU.ED PARAMETER 12" EXTENSION 

SPECIFY OUTDOOR RESET?? L .. 

11.1NSTALLAIJ. PIPING AND DUCTWORK TO MAINTAIN 

Y. HRVWALL TERMINATION MAXIMUM HEADROOM. 	 FTR SYSTEM PUMP P-1 (APARTMENTS) YEI'IMAIRTANOEM TRANSITION PROJECT' 

GRUNDFOS ALPHA 15-65F, 314" FLANGE 

12. FIElll MEASURE SPACES BEFORE ORDERING FINNED CAST IRON CASING, INTEGRAL FLOW CHECK 

E TUBE RADIAT10N. 	 11!>'11110 

BE Merrimack Valley 

RE OOMESTlC HOTWATERLOOP DUCTWORK SPECIFICATIONS: 

PRESSURIE RELIEF VALVE' Habitat for Humanity 

 WATTS REGULATOR34M1), 15CJ PBIG 1. ALL DUCTWORK SHALL BE CONSTRUCTED OF Cl26 

ON GALVANIZED STEEL DUCTWORKSHALLBE 

. HYDRONIC 

PRESSURIE 

SPACE 

RELIEF 

HEATING 

VALVE' 

LOOP 	 FABRICATED 

RESIDENTIAL 

IN 

CODE 

ACCORDANCE 

AND ENERGYSTARVERBION 

WITH THE 20081NTERNATIONAL 

3. Condominium

 WATTS REGULATOR 374A. 30 PSIG 


N 
 Conversion 2. AIJ. DUCTWORK SHALL HAVE SMOOTH TRANSITIONS. 

PRESSURE RELIEF VALVE: ALL SEAMS AND JOINTS SHALL BE FUU. Y AIRSEAL.ED wmi 

. WATTS REGULATOR 374A. 30 PSIG A BRUSH APPLIED MASTIC (RCD MASTICS 118 OR APPROVED 

EQUIVALENT) TO A MINIMUM THICKNESS OF 80 MILS. 100 Parker Street 

 


3.DUCT INSULATION ·ALL OUTSIDE DUCTS (TWO PER HRV) Lawrence, MA 01943

SHALL BE INSULATED. DUCT INSUlATION 

PIPING SPECIFICATIONS' SHALL BE FIBERGLASS WITH PSK FACING AND RATED 

LL 1. WATER PIPE AND RTTlNGS ·WATTS WATERPEX WPFPOB 

 4. AIJ. DUCT SYSTEMS SHALL BE PERFORMACE TlESTED PER 

WITH WATTS PEX FITTING. MORE DETAIL NEEDED? ENERClY STAR VERSION 3 PROTOCOL AND ACCASTANDARO 9 

10 HVAC QUALITY INSTAI.l.ATION VERIFICATION PROrocoLS. 

VALVE· WATTS REGULATOR, BRASB OR BRONZE, 

FUU. PORT. STAINLESB STEEL BAlL 

SIZE

3. SALANCING VALVE-WATTS REGULATOR C$M-<l1, UNE ---a-m-­

 


 
 4. STRAINER-WATTS REGUlATOR, WYE TYPE. BRASS OR ...a8\' Rll.......
 

BRONZE 

5. IN-lJNE ACID NEUTlW.IZER 

H JJM BOILER WORKS MODEL JM-2, 1J2' 

6. FLUE GAS CONDENSAlE DRAIN PIPING- ASTM 

satEDULE oW, SOCKET WELDED. POLYVINYL CHLORIDE (PVC) 

PlASTIC PIPE AND FITTINClS. 

E 


1. BOILER FLUE PIPINCl AND COMBUSTION AIR PIPING· 

ASTM F-441, SCHEDULE 40, SOCKET WELDED, 

1l61311J12 HRV DUCT LAYOUT DRAFT 

CHLORINATED POLYVINYL CHLORIDE (CPYCJ PLASTIC PIPE AND FITTINGS. MARK DATE DESCRIPTION CEll.UIAR (FOAM) CORE PlASTIC PIPE SHALL NOT BE 

IS 

ISSUE: lll/17112 PLUMBER HYDRONIC REVIEW 

 

PERMITTED. 

PROJECT NO: 

CAD DWCl FI.E: MYHill HVAC_BSC.dwg 

S PKERRIGAN 

CHECKED BY' 

COPYRIGHT@ 21112 

BUILDING SCIENCE CORPORATION 

SHEETTIT1..E' 

GENERAL NOTES 

HVAC DESIGN 

SCALE AS NOTED ® 

140

M-0 
--

BUILDING SCIENCE 

CORPORATION 

10" X 10" DUCT 

EXHAU9TO MODEL SDR 011 

SUBDUCT{T'I'P) 

w 

STACK#l AND f3 

112"DOMES11C 

CWMAKHJP 

DOMESTICHW 

FLOOR 

ABOVE GRADE COMMON AREA 

117 R=RN FROM BASEBOARD$; 0.1 -0.7 GPM 

120F 

.I __/ROOMTSTAT 

WArn; FLOWMETER MANIFOLD -----<t) 

117SUPPLYTOBASESOARDS' 0.1-0.7GPM 

BASEMENT COMMON AREA 

117 R=RN FROM BASEBOARD$; 0.1 -0.7 GPM 

.I __/ROOMTSTAT 

WATnl FLOWMETER MANIFOLD -----<t) 

120F 

117SUPPLYTOMSESOARDS; 0.1-0.7GPM 

ffi 

DOMESTIC HW (IF NEEDED IN FUTURE) 

OOMES11C CWOF NEEDED IN FUTURE) 

31-4"HWS 

AIR SEPARATOR 

wmtAUTOMAllC 

AIR VENT 

112"DOMESTIC 

CWMAKE-UP 

5GPM 

EXPANSION TANKET-2 

SET AT 10 PSIG PRECHARGE FLOOR 

30 FOREST STREET SOMERVILLE, MA 

T: (978) 589-5100 F: (978) 589-5103 

www.buildingscience.com 

CONSULTANT; 

., I' 

L .. 

PROJECT; 

Merrimack Valley 


Habitat for Humanity 


Condominium 


Conversion 


1 00 Parker Street 


Lawrence, MA 01943 


U.B. ef En•I1D' ---a.mo05/W'l21 HRY DUCT LAYOUT DRAFT 

MARK I CAllE I DE9CRIP110N 

ISSUE: 01117112 PLUMBER HYDRONIC REVIEW 

PROJECT NO; 

CAD DWQ FI.E; MVHfH HVAC_BSC.dwg 

PI<ERRIGAN 

CHECKED BY: 

ODPYRIGHT@ 2012 

BUILDING SCIENCE ODRPORATION 

SHEETTII\.E; 

HVAC 

SCHEMATICS 

COMMON AREAS HEATING SlXTM -IYPICAbWAJER PIPING SCHEMAT!G SCALE AS NOTED ® 

141

M-1 
--

BUILDING SCIENCE 

CORPORATION 

!:!9ll!!; 

1. READ AND UNDERSTAND INSTAUATION NOTES ON 

SHEET M.O BEl'ORE INSTAU.ING. 

Unit 2 

IM1t/tllnlng 

[Q] [Q] 

Ralldlnt starage 

IIIDROPPED CEILING NOTES ABOUT PROPER INSTAUATIONnl 

30 FOREST STREET SOMERVILLE, MA 

T: (978) 589-5100 F: (978) 589-5103 

www.buildingscience.com 

CONSULTANT: 

., .. 

L .. 

PROJECT: 

Merrimack Valley 


Habitat for Humanity 


Condominium 


Conversion 


100 Parker Street 


Lawrence, MA 01943 


U.B. ef En•I1D' ---a.m.­

Dli/30/12 I HRVDUCT LAYOUT DRAFT 

MARK I DATE I DESCRIPTION 

ISSUE: 01117112 PLUMBER HYDRONIC REV1EW 

PROJECT NO: 


CAD DWQ FI.E: MVHfH HVAC_BSC.dwsl 


DRAWN BY: PI<ERRIGAN 


CHECKED BY: 


COPYRIGHT@ 2012 

BUILDING SCIENCE CORPORATION 

SHEETTITl..E: 

BASEMENT 

HRV I KITCHEN 

EXHAUST LAYOUT 

SCALE AS NOTED ® 

142

M-2 

--

lM'Ig 

it 3 

UCT TO BE ROLJTED 

UGH Fl.OORJOIST. 

WORKLOCA1ED IN 

R JOISTS TO BE 

PED WITH 1 HOUR 

RATED DUCT WRAP. 

Unit 4 

D) 

O). 

OM 

LL 

 TO 

 R-ll 

ROM 

Uvlng-Eatlng 

Unit 5 

IMIItlg Roam Kitchen 

HRV DUCT TO BE ROII!Bl 

THROUGH FLOOR JOIST. 

DUClWORKLOCATED IN 

Fl.OOR JOISTS TO BE 

WRAPPED WITH 1 HOUR 

FIRE RATED DUCT WRAP. 

Bedroom 

BUILDING SCIENCE 


CORPORATION 


30 FOREST STREET SOMERVILLE, MA 

T: (978) 589-5100 F: (978) 589-5103 

www.buildingscience.com 

CONSULTANT: 

., .. 

L .. 

PROJECT: 

Merrimack Valley 


Habitat for Humanity 


Condominium 


Conversion 


100 Parker Street 


Lawrence, MA 01943 


U.B. ef En•I1D' ---a.moI HRV DUCT LAYOUT DRAFT 

MARK I DATE I DESCRIPllON 

ISSUE: 01117112 PLUMBER HYDRONIC REVIEW 

PROJECT NO: 


CAD DWQ FI.E: MVH1H HVAC_BSC.dwg 


DRAWN BY: PI<ERRIGAN 


CHECI<IEDBY: 


ODPYRIGHT@ 2012 

BUILDING SCIENCE ODRPORATION 

SHEET TITUE: 

FIRST FLOOR HRV I KITCHEN 

EXHAUST LAYOUT 

SCAUE AS NOTED ® 

143

M-3 

10"X10" EAO UP & Dll 

• 

WITH SUBDUCT 

lrt,W:.m'ffff/.m'&/&/&/&/.m'&

I Unit 8 

rHRVDUAL ROOF 1/ EXTERIOR HOOD MOUNTED 

HRV EXHAUST 

rno 

e"DIA\

17CFM EAO

A 

u-­

AU. HRV AND KITCHEN 

EXHAUST DUCTS IN UNIT B 

SHALL BE LOCATED IN THE 

UNVENTED SUSPENDEND 

CEILING SPACE. ALL 

DUCTWORK TO BE 


WRAPPED WITH 1 HOUR 


FIRIE RATED DUCT WRAP. 


HRV EXTERIOIR DUCTS TO BE 
ROUTED THROUOH THE ROOF. 


... 

BE 

H 

TS n. 

D 


D 


P. 


ROOF 

MOUNTED 

HRV ;.-; 

INTAKE

F 1

W&&ff&&.#ffh'HM

BUILDING SCIENCE 


CORPORATION 


30 FOREST STREET SOMERVILLE, MA 

T: (978) 589-5100 F: (978) 589-5103 

www.buildingscience.com 

CONSULTANT' 

., .. 

L .. 

PROJECT' 

Merrimack Valley 


Habitat for Humanity 


Condominium 


Conversion 


100 Parker Street 


Lawrence, MA 01943 


---&.!11'­

115130112 I HRV DUCT LAYOUT DRAFT 

MARK I DATE I DESCRIPl10N 

ISSUE: 118117112 PLUMBER HYDRQijiC REV1EW 

PROJECT NO: 

CAD DWO FI.E: MVHIH HVAC_BBC.dwg 

DRAWNBV' PI<ERRIGAN 

CHECICIEDBY' 

COPYRIGHT@ 2012 

BUILDING SCIENCE CORPORATION 

SHEETTITLE' 

SECOND FLOOR 

HRV I KITCHEN 

EXHAUST LAYOUT 

SCAUE AS NOTED ® 

144

M-4 

--

BUILDING SCIENCE 


CORPORATION 


r1D"X1D" 

/ EADDN 

N!Fft---r---F=-­

h c 

u 

10"X10' 

EADDN 

Kitch NTEDAmC cEj 

•/Eattla 0 

D) 


01. 


M 

. 

TO 

IW 

OM 

AU. HRV AND KITCHEN 

EXHAUST DUCTS IN UNIUAND 10 

SHAU. BE LOCATED IN THE 

UNYENTED SUSPENDEND 

CEILING SPACE. AU. 

DUCTWORK TO BE 

WRAPPED WITH 1 HOUR 

FIRIE RATED ouCTWRAP. 

HRV EXTERIOR DUCTS T1D BE 

ROUTED THROUGH THE ROOF. 

I 
 Exllltlng roof dac:k 


Lr30 FOREST STREET SOMERVILLE, MA T: (978) 589-5100 F: (978) 589-5103 www.buildingscience.com CONSULTANT: ., .. L .. PROJECT: Merrimack Valley 
 Habitat for Humanity 
 Condominium 
 Conversion 
 100 Parker Street 
 Lawrence, MA 01943 
 U.B. ef En•I1D' ---a-m-­ 0&"-ID/12 I HRV DUCT LAYOUT DRAFT MARK I DATE I DESCRIPllON ISSUE: 01117112 PLUMBER HYDRONIC REVIEW 

PROJECT NO: 


CAD DWQ FI.E: MVHIH IIVAC_IIIIC.IMg 


BY: PI<ERRIGAN 


CHECKED BY: 


COPYRIGHT@ 2012 

BUILDING SCIENCE CORPORATION 

SHEET TITUE: 

THIRD FLOOR 

HRV I KITCHEN 

EXHAUST LAYOUT 

SCAUE AS NOTED ® 

145

M-5 

--

BUILDING SCIENCE 


CORPORATION 


u 

30 FOREST STREET SOMERVILLE, MA

..._ .. ; T: (978) 589-5100 F: (978) 589-5103 

www.buildingscience.com 

CONSULTANT' 

0 

..... 

UNITB 

INTAKE 

FAN 0 

STACKf2):b • 

DGE - ..•• :· •._.. • J_.,l j ... ., I'

HRV 

OF • " 

0 

0 0 

I--

Kitchen llnW 

L ..

I-­ (KITCHEN EXHAUST EXHAUST STACKII2): FAN),

LOCATE MN 10FT FROM EDGE PROJECT: 

OF FLAT ROOF 

rn Merrimack Valley Habitat for Humanity 

Drain Condominium 

Conversion 3" BOI..ERCOMBUSllON AIR 

TERMINATE llOOSE NECKOUllET .., 100 Parker Street 

.. 31F' /liJOVE ROOF; TYP (1!) __l Lawrence, MA 01943 3" BOILER FLUE VENT-----­

• TERMINAlEOL1TlET4W 

ABOVE ROOF; TYP (8) 

GE :I! 

OF ,_-Bath vente ......1 

0 0 

I; .. U.B. D•p•rtrn•nt Gl En•rgy 

..._lit "'' •! . 

('": ---a-m-­ 0 

...

;c ....., Rllllllllllla..,

1•) 

ti:fL 

D D 

UNITB 0613n'12 I HRV DUCTLAYOLIT DRAFT HRV 

INTAKE MARK I DATE I DESCRIPTION rNr

0 ..

,,

, ISSUE: 01117112 PLUMBER HYDRONIC REVIEW 1.,., 

J PROJECT NO: 

CAD owe FI.E: MVHIH IIVAC_IIIIC:.<Mg 

ROOF TERMINATION NOTES; 

DRAWN BY' PKERRIGAN l• / 

DUCED) 1. ROOF HRV INTAKES SHALL BE LOCATED 10FTAWAY FROM v APPI.JCANCE OR PLUMBING VENT OPENINGS. INTAKES SHALL BE CHECKED BY' 

LOCATE02 FT AIIOIIE THE ROOF SURfACE. 

D COPYRIGHT@ 2012 

BUILDING SCIENCE CORPORATION 

2. ROOf HRV INTAKE AND EXHAUST TERMINATIONS SHALL BE A IF' 

DUAL 

14880). ROUND ROOF CAP SUCH AS AMERICAN ALOES MOOEL RC- 4311. ROOF CAP SHALL HAVE AT LEAST A 12' EXTENSION TO AVOID SNOW 

TH A SHEETTIT1..E' 

THROOM ACCUMULATION. 3. ALL ROOF PENETRATIONS SHALL BE PROPERLYAIRANDWAlER 

IS SEALED PERTHEARCHilECTURAL fl.OOR PLANS AND DETAILS. 

S. AUL 


IJSH 
 ROOF 

LENT) TO 

ED TO IW HRV I KITCHEN

WAY FROM EXHAUST LAYOUT 

SCALE AB NOTED ® 

146

M-6 
--

BUILDING SCIENCE 


CORPORATION 


 1 

Unit 2 

IMigJillnhg 

Q] [Q] 

 

 BE 

BE 

30 FOREST STREET SOMERVILLE, MA 

T: (978) 589-5100 F: (978) 589-5103 

www.buildingscience.com 

CONSULTANT' 

., .. 

L .. 

PROJECT' 

Merrimack Valley 


Habitat for Humanity 


Condominium 


Conversion 


100 Parker Street 


Lawrence, MA 01943 


U.B. ef En•I1D' ---a.mo-


MARK I DAlE I DESCRIP110N 

ISSUE: 01117112 PLUMBER HYDRONIC REV1EW 

PROJECT NO: 


CAD DWQ FI.E: MVHIH HVAC_IIIIC.IMg 


PI<ERRIGAN 

CHECKED ay, 

COPYRIGHT@ 2012 

BUILDING SCIENCE CORPORATION 

SHEETTITl..E' 

BASEMENT 

HYDRONIC 

LAYOUT 

SCALE AS NOTED ® 

147

M-7 

--

BUILDING SCIENCE 


CORPORATION 


UW!g-Eatlng 

Unit 5 

lllllmgRacm kltch., 

.. 

r

.., 

:J: 

l:l 

.. 

I;; 

Unit 4 Dn Up 

19R 

30 FOREST STREET SOMERVILLE, MA 

T: (978) 589-5100 F: (978) 589-5103 

www.buildingscience.com 

CONSULTANT: 

., .. 

L .. 

PROJECT: 

Merrimack Valley 


Habitat for Humanity 


Condominium 


Conversion 


100 Parker Street 


Lawrence, MA 01943 


U.B. ef En•I1D' ---a.mo-


MARK I DATE I DESCRIPnON 

ISSUE: 01117112 PLUMBER HYDRONIC REVIEW 

PROJECT NO: 

CAD DWQ FI.E: MVHIH HVAC_IIIIC.IMg 

PI<ERRIGAN 

CHECKED BY: 

COPYRIGHT@ 2012 

BUILDING SCIENCE CORPORATION 

SHEETTIT1..E: 

FIRST FLOOR HYDRONIC 

LAYOUT 

SCALE AS NOTED ® 

148

M-8 

BUILDING SCIENCE 


CORPORATION 


30 FOREST STREET SOMERVILLE, MA 

T: (978) 589--5100 F: (978) 589--5103 

www.buildingscience.com 

CONSULTANT: 

.. ., 

L -' 

PROJECT: 

Merrimack Valley 


Habitat for Humanity 


Condominium 


Conversion 


100 Parker Street 


Lawrence, MA 01943 


MARK I DATE I DESCRIPTION 

ISSUE: 01117112 PLUMBER HYDRONIC REVIEW 

PROJECT NO: 

CAD DW<l FI.E: MVHIH HVAC_IIIIC:.<Mg 

BY: P KERRIGAN 

CHECKED BY: 

COPYRIGHT@ 2012 

BUILDING SCIENCE CORPORATION 

SHEETTITl.E: 

SECOND FLOOR 

HYDRONIC 

LAYOUT 

SCALE AS NOTED ® 

M-9 


H 

r-r3" Fl.UE 

UP&DN 

3"COMBAIR 

UP&DN 

3" COMB AIR UP 3" Fl.UE UP 

b ]f

:::LJI 

a• COMB AIR UP 

a• Fl.UE UP 

illI 


h 
 -

 

8 LF HE2

6LFHE2 II 3LFHE2 

llllrno 

H'------IIBID 

I Hit 

tll 

.. 

:I: 

... 

Unit 8 

(!) 

.. 

3"COMBAIR 

UP&DN 

;; 3" Fl.UE

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