# Presentation: 033987

## Commercial Envelope Requirementsof the 2006 International EnergyConservation Code

- U.S. Department of Energy Building Energy Codes Program

## Major Changes to the Envelope Requirements

- Commercial Provisions Contained in Chapter 5
- IECC
- ASHRAE 90.1-2004
- New Envelope Tables
- New Requirements for Metal Buildings
- Buildings Limited to 40% Glass to Wall Area

**Notes:**
The 2006 IECC provides the option of using 90.1-2004 to show compliance.

Changes in 2006 IECC – 37 tables in 2003 IECC, dropped down to 1 table; 19 climate zones dropped to 8 climate zones; code is much more streamlined.

New requirements for metal buildings as they are thermally inefficient; insulation requirements changed and also techniques to insulate

If more than 40%, must use Section 506, Building Performance Approach or 90.1.

## Introduction to the Energy Code Compliance Process

**Notes:**
Same as 2003 IECC although some reference standards and section numbers have changed.

Section 1 – change from 2003 is how conditioned spaces are covered and what is considered conditioned space.

Temperature increments were used in 2003 to define conditioned spaces; in 2006, definition is any space with space conditioning equipment is conditioned; if less than 3.4 Btu/sf, considered low energy use and not conditioned.

Once you know the building has to comply with code, it must comply with envelope, mechanical, and lighting requirements in the code.  Different compliance options are available for each.

## Does My Project Need to Comply with the IECC?

- All Buildings Other Than:
- One- and two-family residential
- R-2, R-3, R-4 three stories or less in height

**Notes:**
Any conditioned space needs to comply with Envelope requirements.

Commercial building is any building other than one- and two-family residential or R-2, R-3, R-4 three stories or less in height.  Three stories is important to pay attention to number of floors and occupancies in building.

2006 IECC does not specifically reference one- and two-family residences, but it is implied in the code.

## Introduction to the Energy Code Compliance Process

**Notes:**
Options to show compliance:  Section 502 of IECC, has 40% cap on window-wall ratio (WWR) or can Section 506 in IECC which allows for higher glass areas, etc. or use 90.1-2004 Section 5.

## What is the Building Thermal Envelope?

- Roof/Ceiling Assembly
- Wall Assembly
- Vertical Fenestration and Skylights

- Floor Assembly
- Slab Edge
- Below Grade Wall

**Notes:**
The components listed are considered the building thermal envelope.

Roof – insulation cannot be on a dropped ceiling.

Wall – changed slightly from 2003 IECC; interior wall definition in the past (between conditioned and unconditioned space) has been removed.  In the 2006 IECC, any wall that surrounds conditioned space is now considered an exterior wall.

Vertical – significant changes related to site-built products

Floor – floor over outside air or over unconditioned space – some differences related to areas with cavities and if mass floor

Slab – 2003 IECC required insulation in many cases; in the 2006 IECC, slab insulation is only required in cold, extreme climates unless it’s a heated slab

Below grade wall = 85% below grade

## What are My Options for Complying with the IECC?

- Chapter 5 of the IECC General Prescriptive Approach
- Use for ≤ 40% of gross wall area in glazing
- Section 506 Total Building Performance Approach
- ASHRAE/IESNA Standard 90.1-2004

**Notes:**
Compliance options:  Chapter 5 of the 2006 IECC – 502 or 506, or 90.1-2004

Must use Section 506 or 90.1 if over 40% WWR

## Climate Zones—2006 IECC

- Determining Your Climate Zone is the First Step in the Process

**Notes:**
Major change between the 2003 and 2006; 19 climate zones to 8.  

Subdivided based on levels of humidity and moisture in climate zone:  marine, dry, and moist.  Hottest climate zone is 1.  The higher the number, typically the colder the climate.  Moisture/humidity comes into play for economizer and some thermal envelope requirements and vapor retarder requirements.

Same climate zones are also used in 90.1-2004.

## Compliance with Chapter 5 Prescriptive Approach

**Notes:**
New prescriptive table.

Most tables were eliminated/consolidated from 2003 into this one table.

Left column lists assemblies.  Across the top are climate zones, and based on assembly type and climate zone, insulation R-value requirement or U-factor requirement is dictated.  Multiple types of assemblies within each category.

In the table, ci = continuous insulation (not broken by framing members)

Metal buildings are covered in a separate table.  Thermal breaks were not always required in 2003 but are always required in 2006.

Mass walls have a separate table also.

Below grade – NR = no requirement; in most cases do not have to insulate a below grade wall.

Mass floors – all requirements are ci

Joist framing – assumes insulation between framing

Slabs – typically don’t have to be insulated – only in climate zone 8; if heated, even in hottest climate zone, it must be insulated to levels in the table.

New category in 2006 – opaque doors – in some climate zones doors must be efficient.

## Compliance with Chapter 5 Prescriptive Approach

**Notes:**
Metal buildings – brand new table/requirements.  In certain climate zones, metal buildings are now required to have higher insulation levels.

Roofs – R-19 + R-10; install R-10 insulation perpendicular to the roof framing and then install R-19 parallel to the purlins.  R-10 insulation supports the R-19.

Higher roof insulation required in 1, 7, or 8 – either hottest or coldest climates.

Thermal blocks will always be required.  Doesn’t matter what type of roof system.

Walls – in some zones, will have to install double layers of insulation.  In the example of R-13 + R-13, one layer of R-13 actually creates a thermal barrier between the roof and the wall skin and metal framing.  The other R-13 provides the thermal insulation needed to keep the building efficient.  

## Roof R-value (502.2.1)

- Roof R-value Requirements Based on Assembly Type/ Insulation Placement

- Insulation entirely above deck
- Metal buildings
- Attic and other

**Notes:**
Always have option of installing insulation entirely above deck, regardless of structure below it.

Metal buildings – typically R-19 required or double layers; will always need thermal breaks.

## Roof R-value

- Insulation Completely Above Deck

- Insulation considered continuous (*CI*)
- Insulation thickness can vary ≤ 1” when area weighted U-factor meets the requirements of Table 502.2(1)

**Notes:**
2006 IECC change is realization that even ci above a roof deck is not continuous.  Code allows the thickness to vary if a weighted average is done.

Accounts for installation of things like roof drains which are needed in a flat ceiling or built-up roof system.  There is now an allowance to account for varying thicknesses of insulation.

## Roof R-value

- Insulation Placed On Suspended Ceiling With Removable Ceiling Tiles

- Will not count for code compliance
- Will not comply with Section 502.4.3 – Sealing of the building envelope

**Notes:**
Other recognition in the 2006 IECC, that was implied but not explicitly stated in the 2003 IECC, is that you cannot insulate a dropped ceiling and count it toward code compliance.  The problem is that it is very difficult to adequately seal; because insulation has to be at air barrier.  

## Roof R-value

- Metal Buildings
- R-5 thermal blocks required on all metal buildings
- Climate Zones 1, 7 and 8 require two layers of insulation (R-19 + R-10)
- R-10 draped perpendicularly to the purlins
- R-19 running parallel to the purlins supported by the R-10

**Notes:**
Major change from 2003 IECC.

R-5 thermal breaks required on all metal buildings, regardless of glass % or where the building is located.

Climate zones 1, 7, 8 require double layers.

## Roof R-value

- Ceilings With Attic Spaces
- Install insulation between framing
- R-30 in most Climate Zones
- R-38 in Climate Zones 7 and 8

**Notes:**
If have standard vented attic.  Colder climate zones require R-38.  No requirements for special truss systems.

## Wall R-value

- Mass walls
- Walls weighing at least 35 lbs/ft2 of wall surface area, or
- 25 lbs/ft2 of wall surface area if material weight is ≤ 120 lb/ft3

**Notes:**
Requirements have changed – wall systems are defined differently.  Mass walls are now defined based on weight per sf.

Concrete masonry units and tilt-up concrete wall systems still fall within this category.

## Mass Walls – Concrete Masonry Units

- Climate Zones 3 and 4 – Can use integral insulation instead of R-5.7 ci
- Concrete block walls must comply with ASTM C 90, and
- Ungrouted or partially grouted @ 32 inch. o.c. or less vertically or 48 inch. o.c. or less horizontally, and
- Ungrouted cells must be filled with insulation material ≤ of 0.44 Btu-in./h-ft2 F
- Climate Zones 3A (Below “Warm-Humid” line) and 3B
- No insulation required for mass walls

## Wall R-value

- Wood and metal framed walls
- Cavity insulation or cavity plus continuous (ci)
- Continuous insulation not broken up by framing members e.g. rigid board insulation

**Notes:**
In some cases, insulation is required to be both in cavity and continuous.  Both typically only required in metal-framed wall system.

## Metal Building Walls (Table 502.2(2))

- Climate Zones 1 – 4 except Marine
- R-13 insulation installed perpendicular to the girts and compressed by the metal skin
- Climate Zones Marine 4 and higher
- R-13 insulation installed perpendicular and continuously to the girts
- Addition R-13 insulation installed within the framing cavity

## Below Grade Walls (502.2.4)

- What is a below grade wall?
- Basement or first-story walls ≥ 85% below grade
- Insulation must extend down 10 ft from the finished grade level or to the level of the floor, whichever is less

**Notes:**
Only in climate zones 7 and 8, install insulation 10 ft from the finished grade or level to the floor level; should be continuous insulation.

## Floors Over Outdoor Air or Unconditioned Space (502.2.5)

- Joist/Framing
- Insulation installed between framing
- Mass Floors
- Materials weighing 35 lbs/ft2, or
- 25 lbs/ft2 if material weight is ≤ 120 lbs/ft3
- Insulation installed continuously

**Notes:**
Joist/framing – might be small office building that looks similar to a residence.  Cavity insulation is installed between framing.

Mass – continuous insulation is required.  Colder climates require anywhere from R-10 ci to R-15 in climate zones 7 and 8.

## Slab-on-Grade Floors (502.2.6)

- Unheated slab – insulation not required except in Climate Zone 8
- Heated slabs – insulation required in all Climate Zones

**Notes:**
2006 IECC eliminates need to insulate unheated slabs except in climate zone 8.  Important to note, however, that freeze protection may be required by other types of codes (not IECC).

Heated slab – example is radiant heating coils running through the slab or uninsulated ductwork running through it; always have insulation requirements – even in hotter climates.

## Opaque Doors (502.2.7)

- Doors having < 50% glass area
- Swinging doors
- Meet U-factor requirement
- Roll-up or sliding doors
- Climate zones 1 – 5 and Marine 4:  U-1.45
- Climate zones 6 – 8:  U-0.50

**Notes:**
Two categories:  swinging or roll-up/sliding doors.  Must meet U-factor requirements.

## Compliance with Chapter 5 Prescriptive Approach

**Notes:**
One of the major changes is this new glazing table and how glazing is handled in the code.  A lot of categories were added to reflect different site-built products.

Products are listed in the left column and climate zones are across the top of the table.  Limited to 40% - if more than 40%, must use a different compliance approach.

SHGC – in hotter climates, SHGC requirements are down to .25 with no overhangs.  For certain overhangs, can substitute overhang for low SHGC window.

SHGC requirements for skylights are new for 2006 IECC.

## Vertical Fenestration Requirement (502.3.1)

- Percentage of Vertical Fenestration Area to Gross Wall Area

- Allowed up to 40% maximum of above grade wall

**Notes:**
Slight modification from 2003 IECC:

Wall between conditioned and unconditioned space can now count toward your gross wall area.

## Vertical Fenestration Requirement (502.3.1)

- Based on above-grade wall area (gross)
- Includes walls between conditioned space and unconditioned space or the great outdoors
- Includes walls that are > 15% above grade
- Total fenestration area (includes frame and glazing)
- Does not include opaque door area

**Notes:**
Essentially any wall that surrounds conditioned space now counts towards gross wall area.

## Fenestration U-factor (502.3.2)

- Framing Materials Other Than Metal w/ or w/o metal reinforcement or cladding

- Includes vinyl and wood frame products or other non-metal frames
- Typically manufactured fenestration products

**Notes:**
Typical in small professional office buildings and low-rise commercial construction with smaller square footages.

Get into low-e requirements at about climate zone 5.

## Fenestration U-factor 

- Metal framing with or without thermal break

- Curtain Wall
- By definition:  Fenestration products used to create an external nonload-bearing wall that is designed to separate the exterior and interior environments

**Notes:**
Historically, there has been a documentation problem related to site-built products.  The 2006 IECC tries to address this by defining what a curtain wall is.

## Fenestration U-factor 

- Metal framing with or without thermal break

- Storefront
- By definition:  A nonresidential system of doors and windows mulled as a composite fenestration structure that has been designed to resist heavy use and possible abuse and provide a high level of resistance to window load and impact from wind borne debris

**Notes:**
Code also defines storefront.  NFRC rated or use default values.

## Fenestration U-factor 

- Metal framing with or without thermal break

- Entrance Door
- By definition:  Fenestration products used for ingress, egress an access to nonresidential buildings, including but not limited to, exterior entrances that utilize latching hardware, automatic closers and contain over 50% glass specifically designed to withstand heavy use and possibly abuse

**Notes:**
Typically less efficient than storefront and curtain wall due to manufacturing constraints.

## Fenestration U-factor 

- Metal framing with or without thermal break
- All other
- Includes operable windows, fixed windows and non-entrance doors

**Notes:**
Any products that don’t fall under storefront, curtain wall, or entrance doors fall under “other”.

## Fenestration U-factor (102.1.3)

- How Do You Meet the Requirement?

- Fenestration product rating in accordance to NFRC 100
- Labeled and certified by the manufacturer
- Non-NFRC 100 rated fenestration
- Default Glazed Fenestration U-factor Table 102.1.3(1)

**Notes:**
Has not changed since 2003 IECC.  Has to be NFRC rated or use default value.

## Default U-factors from Table 102.1.3(1) – (2)

**Notes:**
These are the default values.

Tables are by different frame types and then either single pane or double pane.  In colder climate zones, using this table will not be helpful.  Always best to use actual rated values.

## Glazed Fenestration SHGC (502.3.2)

- What is Solar Heat Gain Coefficient?
- “The ratio of the solar heat gain entering the space through the fenestration assembly to the incident solar radiation.”

**Notes:**
Use NFRC 200 rated product or default value.  

SHGC is how much solar gain is blocked by the window.  

MGM Grand has SHGC of about .14, Mandalay Bay has SHGC of about .12, which means it blocks 88% of solar radiation from entering the building.

## Fenestration SHGC Requirements (102.1.3)

- Two Options for Meeting the SHGC Requirements
- Fenestration product rated and labeled to NFRC 200, or
- Select default from Table 102.1.3(3)

**Notes:**
Always best to use rated product.

## Fenestration SHGC Requirements

- The Effect of Overhangs on Fenestration SHGC

- Overhangs allow a higher SHGC product to be installed
- Projection factor must be calculated

**Notes:**
PF greater than .25 in climate zones 4+ eliminate the need to install a low SHGC window.

PF is calculated by taking the distance from the window pane to the edge of the overhang divided by the distance from the bottom of the overhang to the bottom of the window.

## Skylight U-value/ SHGC

- Limited to ≤ 3% of Roof Area
- U-factor and SHGC Based on Material Type
- Glass or Plastic
- NFRC 100 Rating for U-factor or Default Table

**Notes:**
If over 3%, must use a different compliance method.

NFRC rated or use default value.

## NFRC 100 Rating for U-factor or Default Table

**Notes:**
Far right side of the table are the skylight columns.  Best value you can get on the table is 1.05, so it’s best to use actual value rather than default.

## Mandatory Requirements

- Sealing of the Building Envelope *(502.4.3)*
- All penetrations, openings, joints and seams in the building envelope must be sealed.  Materials that can be used include:
- Caulking
- Gasketing
- Tapes
- Moisture vapor-permeable wrapping material

**Notes:**
Regardless of how much glass, insulation levels, etc. there are mandatory requirements that must be met.

Seal up penetrations in the building envelope.  This is just a list of examples of types of materials that can be used...must be durable and allow for expansion and contraction.

## Mandatory Requirements

- Sealing of the Building Envelope *(502.4.3)*

- Sealing materials spanning joints between dissimilar materials must allow for expansion and contraction

**Notes:**
Examples of sealing.  Foam is an example of how to air seal.  Bottom picture shows sealing window.

## Mandatory Requirements (502.4.4)

- Outdoor Air Intakes, Exhaust Openings and Vents Integral to the Building Envelope

- Buildings ≥ 3 stories in height above grade
- Class 1 motorized leakage-rated damper
- Maximum leakage rate ≤ 4cfm /ft2 @ 1.0 inch w.g.
- Buildings < 3 stories in height
- Gravity (nonmotorized) allowed

**Notes:**
Air leakage – exhaust openings and vents.

Picture on bottom shows internal view of relief dampers; picture on top is exterior view.

## Mandatory Requirements (502.4.5)

- Loading Dock Weatherseals

- Equip cargo doors and loading dock doors with weatherseals
- Goal is to restrict infiltration

**Notes:**
Air leakage – loading dock weatherseals; only required if loading dock is a conditioned space.  The weatherseals drastically reduce infiltration.

## Mandatory Requirements (502.4.6)

- Vestibules on Entrance Doors
- Required to reduce infiltration into spaces
- Required on entrance doors leading into spaces ≥ 3,000 ft2
- Doors must have self-closing devices
- Exceptions
- Buildings in Climate Zones 1 and 2
- Doors from a guest room or dwelling unit
- Doors used primarily for vehicular movement, material handling and adjacent personnel doors

**Notes:**
Air leakage – vestibules.  Essentially must be placed on exterior doors leading from/into a space greater than 3000 sf.  Must have self-closing doors and be designed so doors don’t have to open and close at the same time.

Hotter climate zones (1 and 2) are not required to have vestibules.

## Mandatory Requirements (502.4.7)

- Recessed Luminaires Installed in the Building Envelope

- Type IC rated w/no penetrations in the fixture and sealed or gasketed to prevent air leakage
- Type IC or non-IC rated installed in a sealed box with ≥ 1⁄2” clearance from combustible material and ≥ 3” from insulation
- Type IC rated and tested in accordance with ASTM E 283 to allow ≤ 2.0 cfm of air movement

**Notes:**
Air leakage - Recessed can lights requirements apply if cans are installed in building envelope.  The requirements do not apply if the cans are installed in a drop ceiling.

IC = insulation contact

Three options to comply.  Second option (sealed box) is usually least desirable from a cost standpoint.

## Mandatory Requirements (502.5)

- Moisture Control
- Approved vapor retarder required on all unvented framed cavities
- Exceptions
- Climate Zones 1 – 3
- Where moisture or its freezing will not damage the materials
- Where other approved means to avoid condensation are provided

**Notes:**
Moisture control.

Any unvented framed cavities (wall, roof/ceiling, floor) must have vapor retarder installed on the warm-in-winter side of insulation. 

Some exceptions.  If use “other approved means”, must have building official approval.