Iecc Residential Code Overview

IECC Residential Energy Code Overview

Accelerating Implementation of Building Energy Codes

Impact of Energy Codes • Building energy consumption is almost 40% of total energy use in the US ~65.2% of total U.S. electricity consumption • Buildings are the nation’s largest source of global warming pollution

 The Average home emits twice as much greenhouse gases as the average car.  In 2006, 2.3 million housing units permitted in US (NAHB)

• Energy Prices continue to increase

VALUE of Energy Codes Affects ALL new buildings By • • By • • By • •

2010: Almost 5 million new housing units Over 233 billion sq feet commercial floor space 2020: 23.4 million new housing units Over 1 trillion sq feet commercial floor space 2030: Over 41 million new housing units Over 2 trillion sq feet commercial floor space Source: EIA, Annual Energy Outlook 2008

VALUE of Energy Codes Establish a foundation for energy and green programs: • • • • •

ENERGY STAR, LEED homes and commercial buildings, ASHRAE Standard 189 Building America/ federal tax incentive, and Net-zero energy buildings

What is the IECC? A Required Minimum Level of Energy Efficiency In New Residential and Commercial Construction

Code Status

Energy Code Requirements Universal (Basic) requirements (apply everywhere):  Duct insulation and sealing  Infiltration control • Including recessed cans Climate Specific Requirements:  Foundations • Basements • Slabs • Crawlspaces  Above grade walls  Skylights, windows, and doors  Roofs  Solar Heat Gain Coefficient in warm climates

Definition of Conditioned Space/ Thermal Envelope

Outdoors

Conditioned Space

The intent of the energy code is to regulate the design of the building envelope to enable the effective use of energy.

Building Envelope Specific Requirements • Building Envelope consists of: • Fenestration • Ceilings • Walls • Above grade • Below grade • Mass walls

• Floors • Slab • Crawl space

attic

Conditioned space

R-Values • Higher R-value = Better Insulated R-30 • R-value Applies to: 

 

All Walls Raised Floors Roofs

R-19

R-11

U-Values

• Lower U-value = Better Insulated • U-value applies to: Windows Skylights Doors

• U=1/R

Single Pane U = 1.05

Double Pane U = 0.50

Double Pane Low-E Film U = 0.35

Compliance Who Must Comply? Basic Requirements Insulation & Window Requirements Prescriptive Package

REScheck Software

Scope Residential Buildings: • IRC only for single-family, duplex, and townhouses

• IECC has all low-rise (1-3 stories) houses, condos, and apartments [R-2, R-3, R-4], but not hotels/motels [R-1] • All buildings that are not ―residential‖ by definition are ―commercial‖

Additions • Treat as a stand-alone building

• Additions must meet the prescriptive requirements in Table 402.1.1 Exisitng Kithen Existing Family room

Exisitng Dining

NEW Addition SUNROOM

Exisitng Living Room Exisitng Garage

Exisitng Den

Entry

N

Other Areas that Must Comply  Alterations, renovations and repairs e.g., window replacements

Exceptions •Very low energy use buildings (<3.4 Btu/h-ft2 or 1 watt/ft2) •Buildings (or portions of) that are neither heated nor cooled •Buildings designated as historic (Section 101.4.2)

Mixed Use Buildings • Mixed occupancies Treat the residential occupancy under the applicable residential code Treat the commercial occupancy under the commercial code

Change in Occupancy • No action is required if alterations are not made to the building systems

Mel’s Diner

Kurt’s Five & Dime

Compliance Path Who Must Comply? Basic Requirements Insulation & Window Requirements Prescriptive Package

REScheck Software

Basic Requirements • Air Leakage • Vapor Retarder • Materials and Equipment Information • Duct Insulation • Duct Construction • Temperature Controls • HVAC • Piping Insulation • Service Hot Water Systems

Building Plans

Areas for Air Leakage (Infiltration) • Windows and doors • Between sole plates

• Floors and exterior wall panels • Plumbing • Electrical • Service access doors or hatches • Recessed light fixtures

Air Infiltration • Effects of Windwashing  Reduces insulation's effectiveness/installed R-value  Reduces overall comfort  Places unnecessary stress on HVAC system  Increases energy consumption

Effect of Wind on Installed R-Value 14 Wall System Installed R-Value ( F x ft.² x h/BTU)

12

Effective R-Value of wall without proper air sealing

10 8 6

4 2 0 0 *Test data by Holimetrix. ASTM E283,ASTM E1424,C976

5

10

15

20

Wind Speed (M.P.H.)

25

Infiltration Control

Infiltration Control

Chimney Chase Air Sealing Flashing, caulked at each side

Rock wool with heavy duty aluminum foil rolled around it -Caulk to chimney and framing

Another Area To Be Sealed

Another Area To Be Sealed

Sealed !

Through Framing Air Sealing blocking conditioned unconditioned (e.g. - garage, balcony)

Foundations! Seal Foundation Penetrations!

Air Infiltration We have learned much over the years from the “Blower Door Test”  Blower Door Test Depressurizes the House to Measure the Over-all Air Leakage Rate  Attention to Air Sealing is Important!  Air Leakage can account for a major amount of home heat loss, and lead to other performance problems

Energy Star Labeled Homes ®

• Air Leakage Can Be More Than a Third of the Total Heat Loss in a Conventionally Built Home • An Important ENERGY STAR® Requirement is an Air Tightness Test or “Blower Door Test”

Recessed Lighting Fixtures • Type IC rated, with no penetrations between the inside of the recessed fixture and ceiling cavity (sealed and caulked) • Type IC or non-IC rated, installed inside a sealed box of ½" gypsum wallboard or other assembly manufactured for this purpose • Type IC rated, in accordance with ASTM E 283 to be an “Air-Tight” enclosure

Basic Requirements • Air Leakage • Vapor Retarder • Materials and Equipment Information • Duct Insulation • Duct Construction • Temperature Controls • HVAC • Piping Insulation • Service Hot Water Systems

Building Plans

Basic Requirement Vapor Retarders

Siding

 Install on “warmin-winter side” of Building Envelope  Use in unvented framed walls, floors, and ceilings  Must have Perm rating of  1.0 per ASTM E96-80  Careful here!

Vapor

Sheathing Studs & Insulation

Vapor Retarder Sheet Rock

Zone 4 Exempt residential Zone 3 Exempt Commercial

Vapor Retarders One Example: Poly Vapor Retarder (probably a bad idea in any climate)

Another Example: Kraft-Faced Vapor Retarder

Crawl Floor Vapor Barrier

Basic Requirements • Air Leakage • Vapor Retarder • Materials and Equipment

Information

• • • • • •

Duct Insulation Duct Construction Temperature Controls HVAC Piping Insulation Service Hot Water Systems

Building Plans

NFRC Window Information Old

National Fenestration Rating Council (NFRC) product ratings are available on-line at www.nfrc.org

New

Material Identification

Material Identification This Attic Has Been Insulated To

RBy A Professional Insulation Contractor The insulation in this attic was installed by a qualified professional Contractor to the R-value stated above

Certificate of Insulation BUILDING ADDRESS: ______________________________ ______________________________ ______________________________ Installation Date: _______________ Area Insulated Attic Walls Floors

R-Value

Installed Thickness

CONTRACTOR: ______________________________ ______________________________ ______________________________ License #: _____________________ Settled Thickness

Installed Density

No. Bags

Sq. Ft.

I, __________________________________________, (print name) certify that this residence/building has been insulated to the stated R-value and that the installation is in conformance with all applicable codes, standards, regulations and specifications.

Authorized Signature: _____________________________

Date: ____________

Basic Requirements • Air Leakage • Vapor Retarder • Materials and Equipment Information • Duct Insulation • Duct Construction • Temperature Controls • HVAC • Piping Insulation • Service Hot Water Systems

Building Plans

Ducts • Insulation

 Ducts outside the building envelope shall be insulated to R-8  R-6 allowed for ducts in floor trusses • Sealing • Building framing cavities shall not be used as supply ducts

Duct Sealing • Seal and securely fasten all joints, longitudinal and transverse seams and connections with:  welds  gaskets  mastics  mastic-plus-embedded fabric systems  tapes • Unlisted duct tape is not permitted as a sealant on any metal ducts

Duct Systems Air Sealing

Example: Poor Code Details

Solution: Code Details

•Duct Sealing

•Crawl floor Vapor barrier

Duct Installation • Avoid Tight Bends • Minimize Sagging • Size Properly • Place Inside the Envelope (good practice)

Basic Requirements • Air Leakage • Vapor Retarder • Materials and Equipment Information • Duct Insulation • Duct Construction • Temperature Controls • HVAC • Piping Insulation • Service Hot Water Systems

Building Plans

Mandatory Requirements Systems • Controls – 1 T-stat for each separated heating and cooling system. • Heat pump supplementary heat • HVAC piping insulation R-2 (>105 or <55 degrees) • Circulating hot water systems: R-2 Circ. Pump on/off switch

Ventilation and Equipment Sizing •

Ventilation  Outdoor air intakes and exhausts shall have automatic or gravity dampers that close when the ventilation system is not operating

•

Equipment Sizing  IECC references Section M1401.3 of the IRC  Load calculations determine the proper capacity (size) of equipment

• Goal is big enough to ensure comfort but no bigger  Calculations shall be performed in accordance with ACCA Manual J or other approved methods

Compliance/Documentation/Inspections

• Code Official has final authority  Software, worksheets  Above Code Programs

• Electronic media can be used • Construction work for which a permit is required is subject to inspection • Certificate is required

Certificate • Permanently posted on the electrical distribution panel • Shall include the following: R-values of insulation installed for the thermal building envelope including ducts outside conditioned spaces U-factors for fenestration SHGC for fenestration HVAC efficiencies SWH equipment

Compliance Path Who Must Comply? Basic Requirements Insulation & Window Requirements Prescriptive Package

REScheck Software

Compliance Options Residential Bldgs Compliance Options Performance Section 404 (HERS)

Component Method Trade Off

Prescriptive Method

REScheck System

IECC Code Compliance–Three Options Prescriptive

U-Factor and “UA” Alternatives

Simulated Performance (software)

R-values 402.1.1 U-factor

Total Building UA

Simulated Performance Alternative

402.1.4

404

402.1.3

Code Compliance Tools Prescriptive

Total Building “UA” Trade Off

Energy Analysis

Software

None Needed

REScheck Software (Web-based & Desktop)

For example: REM/Design REM/Rate EnergyGauge

U-Factor and Total UA (REScheck Approach) • U-factor Alternative Similar to Prescriptive but uses U-factors instead of R-values • Allows for innovative or less common construction techniques such as structural insulated panels or log walls

• Total UA Alternative Same as U-factor alternative but allows tradeoffs across all envelope components • Approach used in REScheck software

Chapter 4 – Performance Approach Proposed Design

Standard Design

(“Proposed Building Meeting the Energy Code Requirements”)

Energy Use of Proposed Design less than

Energy Estimation Tool

Energy Use of Standard Design

Simulated Performance • Requires computer software with specified capabilities (local official may approve other tools) • Includes both envelope and equipment • Allows greatest flexibility. Credits features such as:  High efficiency furnaces, air-conditioners, etc.  Tight ducts (must be leak tested) or hydronic systems  Exterior shading, favorable orientation, thermal mass, SHGC, etc. • Section 404 specifies ―ground rules‖  These will generally be ―hidden‖ in compliance software calculation algorithms  Very similar ground rules are used in new home federal tax credits and ENERGY STAR Home guidelines

Systems Approach 

  

Homes Meeting ENERGY STAR® Requirements Meet and Exceed the Energy Code Requirements in Chapter 4 of the IECC Typically RemRate or RemDesign Calculations are Performed Using a Sophisticated Computer Program for Accuracy and Provided to You Should be approved by jurisdiction for use in compliance; may require groundwork with muni

www.resnet.org

HERS Home Report: Homeowner ABC Anywhere, USA

Thermal Envelope Prescriptive Package • Sets U-value or R-value requirements based upon: Zone Building component (ceilings, walls, floors, windows, doors)

Windows, Glazed Doors, and Skylights U-factor Requirements: • NFRC Rating for all

Manufactured Fenestration; or • Tables N1101.5 Ufactor Default Table for Windows, Glazed Doors and Skylights Exceptions: Unrated double-pane with thermal break comply in Zones 2 and 3

Thermal Envelope Fenestration • An area weighted average of fenestration can be used to satisfy the U-factor & SHGC requirements  Area-weighted average U-factor and SHGC are subject to hard limits, even in trade-offs  NFRC rated and certified  15 sq. ft. of glazing (and one opaque door) may be exempted (prescriptive path only) • For example, decorative glass on/near front door

Windows – U-Factors • Strict limits on U-factor in northern U.S. (cannot be traded off) U-0.48 maximum in Zones 4 and 5, U-0.40 maximum in Zones 6-8 U-0.75 for skylights in Zones 4-8 These are based on building average; individual windows or skylights can be worse if average meets these requirements

Windows - SHGC • Solar Heat Gain Coefficient SHGC of 0.40 or lower required in the southern U.S. (area-weighted average) SHGC cannot exceed 0.50 even if performance path trade-offs are used (areaweighted average) National Fenestration Rating Council (NFRC) tested

Solar Heat Gain Coefficient

Locations with Window SHGC Requirements

Roofs • R- Value Requirements based on  Continuous insulation  Insulation between framing (cavity)

• Meet or exceed Rvalues

Standard Roof Truss Possibility of ice dam formations

• Ceiling insulation code requirements assume standard truss systems

Cold corners contribute to condensation and mold growth

Raised Heel Truss • Raised Heel/Energy Truss credit if insulation is full height over exterior wall  R-30 instead of R-38  R-38 instead of R-49

Above Grade Walls Insulate walls including those next to unconditioned spaces

Don’t forget to insulate rim joists

Insulation Installation “Cut-To-Fit!”

Right

Wrong

For Wiring Electric Boxes

Right

Wrong

Insulation Installation NO GAPS!

Insulation Voids

Insulation RValue

% of air voids in cavity

Wall Insulation

Insulation Installation

Knee Wall Insulation

Wall Insulation

Mass Walls • What type  Concrete block, concrete, insulated concrete form (ICF), masonry cavity, brick (other than brick veneer), earth, and solid timber/logs

• Provisions  At least 50% of the required R-value must be on the exterior or integral to the wall  If insulation placement cannot be met, provisions for wood frame wall insulation requirements apply (with specific U-factor and R-value exceptions in zones 1— 3)

Wood Frame R-value

Cold-Formed Steel Equivalent R-value

Steel Truss Ceilings R-30

R-38 or R-30 + 3 or R-26 + 5

R-38

R-49 or R-38 + 3

R-49

R-38 + 5

Steel Joist Ceilings R-30

R-38 in 2x4, 2x6, or 2x8 R-49 any framing

R-38

R-49 2x4, 2x6, 2x8, or 2x10

Steel Framed Wall R-13

R-13 +5 or R-15 +4, or R-21 +3

R-19

R-13 + 9 or R-19 +8 or R25 +7

R-21

R-13 +10 or R-19 +9 or R25 +8

Steel Joist Floor R-13

R-19, 2x6 R-19 +6 in 2x8 or 2x10

R-19

R-19 +6, 2x6 R-19 +12 in 2x8 or 2x10

Steel-frame Ceilings, walls, and floors

Below-Grade Walls • > 50% below grade • Zones 1—3: R0 • Zones 4—8: R10 (continuous) or R13 (cavity)

Basement Walls 4’ 4’ 4’

Grade Line

4’



Above Grade per Basement Wall Definition

Basement Walls Interior Studding Exterior Foam

Floors over Unconditioned Space • Space can be unheated basement or a crawlspace or outdoor air • Zones 1—2: R13 • Zones 3—4ab: R19 • Zones 4c—8: R30 • Insulation must maintain permanent contact with underside of subfloor

Crawlspaces

Crawl Space Wall Insulation Crawl Wall Insulation: This practice eliminates the need for insulation in the raised floor above the crawl. Crawl space may not have ventilation openings to the outside Must be mechanically ventilated or supplied with conditioned air (1cfm/50 sqft) Crawl floor must be covered with an approved vapor retarder material

Crawlspace Wall Insulation When crawlspace walls are insulated, foundation vents are not required. Space should be mechanically vented or conditioned.

Crawl Space Wall Insulation

Slab Perimeter R-value

Several Options:

slab

CONDITIONED SPACE finish grade

CONDITIONED SPACE

slab rigid insulation

depth

finish grade

CONDITIONED SPACE

depth

depth

flashing protection board

R-10 Depth = 24” below Grade thru zone 4 and 5

finish grade

slab rigid insulation

Slab Edge Insulation • R-10 (typically 2 inches) insulation in Zones 4 and above • Downward from top of slab a minimum of 24‖ (Zones 4 and 5) or 48‖ (Zones 6, 7, and 8) • Insulation can be vertical or extend horizontally under the slab or out from the building (must be under 10 inches of soil)

Slab Edge Insulation

Compliance Path Who Must Comply? Basic Requirements Insulation & Window Requirements Prescriptive Package

REScheck Software

Implementation Challenges Codes are not being well Implemented: •Training Inadequate

•Misunderstanding of Requirements and how to build them into buildings •Compliance Low We’re NOT getting the projected energy savings OR building better buildings

www.energycodes.gov [email protected]

Field Inspections  Pre-Inspection

 Foundation Inspection  Framing & Insulation Inspection  Final Inspection

Field Inspections (Section 105) Floor Insulation Above Grade Wall Insulation Ceiling Insulation Duct Insulation Vapor Retarder

Slab-Edge Insulation Basement Wall Insulation Crawl Space Wall Insulation

Pre-Inspection

Foundation Inspection

Framing Inspection

Approved Building Plans Energy Code Compliance Certificate Windows/Doors Air Sealing – Penetrations (plumbing, electrical) Recessed Lighting Duct Construction and Insulation HVAC Piping and Insulation

Insulation Inspection

Final Inspection

HVAC Efficiency Thermostats Service Water Heating Air Sealing

PRE-INSPECTION Information on Plans:

 Insulation R-values  Window U-factors  Rough openings for windows and skylights  Equipment efficiencies (if credit has been taken for high efficiency heating and cooling systems)  Duct insulation

Notes on:

 Duct sealing  Air sealing for the building envelope  Circulation loop pipe insulation for water heating  IC rated / air-tight recessed can lights

Foundation Inspection Types of Foundation Insulation:  Slab-Edge  Basement Exterior Insulation (if installed)  Crawl Space (Vented or Un-vented)

Check:

 R-Value or Thickness of Insulation Compared to Plans  Depth of Insulation Compared to Code & Plans  Exterior Insulation Must be Protected  Remember Rim/Band Joist Area

Framing & Insulation Inspection Air sealing:

 Around all plumbing and electrical penetrations, including between the sheet-rock and electrical boxes and where the wiring penetrates the box  Between the duct boot and the sub-floor or sheetrock  At the attic and crawlspace panels  Around Windows and Doors  Between the top and bottom plates and also around the perimeter joist on a floor assembly between two conditioned floors  Around tubs and showers  At recessed lights

Framing & Insulation Inspection  Glazing area, U-factor  Wall Insulation:

 Kneewalls in attics  Perimeter joists  The walls between the house and the garage  Skylight wells

 Attic Insulation  Basement Wall Interior Insulation (if installed)  Recessed can lights

Final Inspection  HVAC Equipment Efficiency  HVAC Ductwork Insulation, Installation and Air Sealing  Piping Insulation  Heat Pump Thermostats  Circulating Hot Water Systems

Technical Support • US-DOE website and Hotline: www.energycode.org Hotline: 1-800-270-CODE • PNNL Codes Website http://www.energycodes.gov/

• ICC Website

www.iccsafe.org

• BCAP www.bcap-energy.org

CONCLUSION Energy Codes Benefit Your Community! Reduce Pollution, Save Energy & Save Money! THANK YOU!