2009 iecc: residential provisions
TRANSCRIPT
RESIDENTIAL PROVISIONSfor the
2009 International Energy Conservation Code
Forrest [email protected]
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Course Objectives
• Understand the importance of the IECC in the built environment
• Understand the development of the IECC/IRC
• Understand the roles of code officials in the IECC
• Understand the application of the IECC requirements to building systems
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What’s Changed from the IECC 2006?
Stringency CZ4 – fenestration U-factor reduced from .40
to .35 CZ5,6 – wood frame wall U-factor reduced
from .06 to .057, minimum R-value (batt only) raised from R-19 to R-20
CZ1,2,3 – Glazed fenestration SHGC reduced from .40 to .30 (except in IRC!)
CZ3 - Basement wall R-value requirements added – 5/13
Reductions allowed in 402.2.1 and 402.2.2 may not be used in the UA tradeoff calculation.
Provisions for attic hatches added (402.2.3) Requirements added for the location (interior vs.
exterior) of insulation in mass walls CZ1,2 - Exceptions for steel frame walls 24”oc (see table 402.2.5)
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What’s Changed from the IECC 2006? Moisture control requirements moved to the IRC (R601.3) Exemptions for 15sf glazed fenestration and opaque doors may not be
used in the UA tradeoff calculation. Envelope air tightness requirements added – blower door or envelope
inspection required (402.4.2 and Table 402.2.2) (2) of (3) options for recessed lighting eliminated – testing per ASTM
E283 now required. Site-built option deleted. Specific mandatory requirements for elements of mechanical systems
specified, replacing Sec 403 (Mandatory) language. Minimum R-8 for attic “supply” ducts – all others min R-6, except if
located in conditioned space. New requirements for snow melt systems and heated pools. High efficacy lighting required for 50% of permanently installed fixtures For performance design, exception added for multiple orientations For performance design, mechanical tradeoffs disallowed, i.e. proposed
design =standard design
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Overview of IECC Requirements
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• Focus is on building envelope– Ceilings, walls, windows, floors, foundations– Sets insulation levels, window U-factors and
solar heat gain coefficients– Infiltration control - caulk and seal to prevent
air leaks• Ducts – seal and insulate• Limited space heating, air conditioning,
and water heating requirements– Federal law sets most equipment efficiency
requirements, not the I-codes• Lighting equipment – 50% of lamps to be
high-efficacy lamps
Does My Project Need to Comply?
• One- and two-family residential – IECC/IRC
• R-2, R-3, R-4 three stories or less in height – IECC/IRC?
• Townhomes – IECC/IRC
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Are These Projects Considered Residential or Commercial?
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Mixed Use Buildings
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• Mixed occupancies– Treat the residential
occupancy under the applicable residential code
– Treat the commercial occupancy under the commercial code
– – Three stories or less– 10% rule (not found in code, in
commentary) www.energycodes.gov
ww
w.energycodes.gov
What Types of Residential Projects are Exempt from the IECC/IRC?
Unconditioned SpacesVery Low Energy use
buildings (<3.4 Btu/h-ft2 or 1 watt/ft2) – envelope
exemption onlyExisting BuildingsUnmodified Parts of ResidenceHistoric Buildings
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Special Topics - Additions
AdditionsWhat is an Addition?
Extension or increase in the conditioned space floor area or height of a building or structure
What Must Comply in an Addition?
New building thermal envelope
New heating and cooling system
New ductworkNew water heating
system10
Special Topics - Additions
How do I Show Compliance for the Addition?Treat addition as a stand alone building
Prescriptive (Component) approachTotal UA AlternativeSimulated Performance Alternative
Demonstrate compliance for the entire house (addition + existing)Used for major renovationPrescriptive (Component) approachTotal UA AlternativeSimulated Performance Alternative
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Conditioned Addition
ExistingHouse
Treat Addition As Stand Alone Building
Conditioned Addition
ExistingHouse
Demonstrate Compliance for Entire House
Special Topics - Alterations
Change to the building envelope, heating and cooling system or water heating system that requires a permit
Must show compliance with the applicable provisions in Code
ExceptionsInstalling storm windows over existing fenestrationReplacing only the glass in an existing sash and
frameExposing existing ceiling, wall or floor cavities that
are already filled with insulationConstruction that does not expose existing roof,
wall or floor cavities
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Special topics - Alterations(Exceptions)• Re-roofing where neither the sheathing or
the insulation is exposed.• Alterations replacing <50% of the
luminaires in a space, provided that interior lighting power is not increased
• Alterations that replace only bulb and ballast, provided the interior lighting power is not increased.
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Regulated Items
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HVAC
DHW
Building ThermalEnvelope Conditioned
SpaceDHWConditioned
Space
Lighting
Structure of the IECC
Chapter 1 – Administration2009 includes new provisions to add exempt elements,
and to align the IECC with administrative provisions in the other I-codes.
Chapter 2 – DefinitionsChapter 3 – Climate Zones, and Materials, Systems, and
Equipment (relocated from 2006 Ch 1)Chapter 4 – Residential RequirementsChapter 5 – Commercial RequirementsChapter 6 – Referenced Standards
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Chapter 1
• Scoping
• Intent
• Third party programs – must meet Mandatory Measures
• Sections 103 (Construction Documents), & 104 (Inspections) – see extensive Commentary notes
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Chapter 2 - DefinitionsAir barrier – Materials “assembled and joined together”, a
single material or combination of materials, i.e. sealants, acting as a system.
Basement wall – “…enclosing conditioned space.” If unconditioned, is classified as a crawl space.
Fenestration – includes skylights & doors.U-value/R-value – Reciprocal values between transmittance
and resistance. Note that U-value includes air films. U-value is calculated through a “component or assembly”, and R-value through a “body”. 402.1.2 (components) and 402.1.3 (assembly) make the difference more clear. C-factor is very similar to U-value (surface to surface instead of air to air) and is used in SHGC calculations.
High-efficacy lamps – minimum lumens/watt requirementLabeled and Listed – borrowed from the IBC
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Chapter 3 – Climate Zones
• Climate Zone map
• Design conditions
• Materials, systems, and equipment – relocated from 2006 IECC Chapter 1
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2009 IECC Climate Zones
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2009 IECC Climate Zones
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Zone 5
Zone 3
Zone 4
Zone 2
Climate Zones
• Warmer Zones (1 – 4B)– Based on Heating and Cooling Degree
Days– Accounts for Humidity
• Requirements include features that reduce cooling energy
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Climate Zones
• Predominately Colder Zones (4C – 8) – Based on Heating Degree Days– Accounts for Humidity– Requirements include features that
reduce heating energy– Higher the climate zone number the
more stringent the requirement
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Code Compliant Attic Insulation
• Attic insulation markers required every 300 square feet for blown-in insulation• Markers must be installed
so that R-value mark is readily observable
• Insulation R-value Required to be Labeled on Pieces ≥ 12” width, or provide certificate for blown or sprayed insulation
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Code Compliant Attic InsulationProvide Certification, Listing (All):
Insulation typeManufacturerR-value Installed
Blown or Sprayed Insulation (Fiberglass or Cellulose)Initial installed thicknessSettled thicknessSettled R-valueInstalled densityCoverage area and number of
bagsSprayed Polyurethane Foam (SPF)
Installed thicknessR-value
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Default U-factors
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IECC Table 303.1.3(1) and IRC Table N1101.5(1)
IECC Table 303.1.3(2) and IRC Table N1101.5(2)
Energy Code Compliance Process
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Mandatory Provisions
Prescriptive
Envelope Section 402
Envelope ProvisionsSection 402.2, 402.3.3 thru 402.3.6 & 402.5 (As Applies)
Simulated Performance Section 405Insulation
Requirements Fenestration
Section 403.2.1 & 404.1
Table 402.1.3
Section 402.3.1 & 402.3.2 (Trade-Off)
Section 402.1.1 & 402.1.2 (Tabular)
Section 402.1.3 & 402.1.4 (Trade-Off)
Project Complies
OR OR
Prescriptive Approach
• Compliance Based on Look-Up Tables• Calculations May be Required (See following)
What Information Do You Need?
• Climate Zone of Proposed Building• Types of Building Assemblies that are Proposed
for the Project
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Prescriptive Approach
You Don’t Need to be concerned with Window (i.e. Fenestration) Area
• Minimum Area Set by Chapter 3 of the IRC
• Maximum Area Set bystructural Constraints and By Cost
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What is Considered Part of the Building Thermal
Envelope?
• Roof/Ceiling Assembly
• Wall Assembly• Windows, Skylights,
and Doors
• Floor Assembly• Slab Edge• Basement Wall• SHGC, U-Factor
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Climate Specific Requirements: Boundary Between Conditioned Space and the
Great Outdoors or Unconditioned Space Includes:
Envelope R-Value• What Counts Towards R-Value?
– Add• Insulation Layers• Insulation between Framing• Insulation over Framing
– Don’t Add• Non Insulation Products• Sheathing less than R-2• Air Films• Air Spaces
– Framing Spaces (or amount) Doesn’t Matter
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Building Envelope
• Roof/Ceiling Assembly
• Wall Assembly
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Building Envelope
• Vertical Fenestration and Skylights
• Floor Assembly
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Overview of Tables 402.1.1(IECC) and N1102.1(IRC) – Component
ApproachCLIMATE
ZONE FENESTRATION
U-FACTORb SKYLIGHTb U-FACTOR
GLAZED FENESTRATIONb,e
SHGC
CEILING R-VALUE
WOOD FRAME WALL
R-VALUE
MASS WALL
R-VALUEi
FLOOR R-
VALUE
BASEMENTc WALL
R-VALUE
SLABd R-VALUE & DEPTH
CRAWL SPACEc
WALL R-VALUE
1 1.20 0.75 0.30 30 13 3 / 4 13 0 0 0 2 0.65j 0.75 0.30 30 13 4 / 6 13 0 0 0 3 0.50j 0.65 0.30 30 13 5 / 8 19 5 / 13f 0 5 / 13
4 except Marine
0.35 0.60 NR 38 13 5 / 10 19 10 / 13 10, 2ft 10 / 13
5 and Marine 4
0.35 0.60 NR 38 20 or 13+5h 13 / 17 30g 10 / 13 10, 2 ft 10 / 13
6 0.35 0.60 NR 49 20 or 13+5h 15 / 19 30g 15 / 19 10, 4 ft 10 / 13 7 and 8 0.35 0.60 NR 49 21 19 / 21 38g 15 / 19 10, 4 ft 10 / 13
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Table 402.1.1Insulation and Fenestration Requirements by Componenta
a. R-values are minimums, U-factors and SHGC are maximums, R-19 batts compressed into a nominal 2 x 6 framing cavity such that the R-value is reduced by R-1 or more shall be marked with the compressed batt R-value in addition to the full thickness R-value.b. The fenestration U-factor column excludes skylights. The SHGC column applies to all glazed fenestration.c. “15/19” means R-15 continuous insulated sheathing on the interior or exterior of the home or R-19 cavity insulation at the interior of the basement wall. “15/19” shall be permitted to be met with R-13 cavity insulation on the interior of the basement wall plus R-5 continuous insulated sheathing on the interior or exterior of the home. “10/13” means R-10 continuous insulated sheathing on the interior or exterior of the home or R-13 cavity insulation at the interior of the basement wall.d. R-5 shall be added to the required slab edge R-values for heated slabs. Insulation depth shall be the depth of the footing or 2 feet, whichever is less in Zones 1 through 3 for heated slabs.e. There are no SHGC requirements in the Marine Zone.f. Basement wall insulation is not required in warm-humid locations as defined by Figure 301.1 and Table 301.1.g. Or insulation sufficient to fill the framing cavity, R-19 minimum.h. “13+5” means R-13 cavity insulation plus R-5 insulated sheathing. If structural sheathing covers 25 percent or less of the exterior, insulating sheathing is not required where structural sheathing is used. If structural sheathing covers more than 25 percent of exterior, structural sheathing shall be supplemented with insulated sheathing of at least R-2.i. The second R-value applies when more than half the insulation is on the interior of the mass wall.j. For impact rated fenestration complying with Section R301.2.1.2 of the IRC or Section 1608.1.2 of the IBC, maximum U-factor shall be 0.75 in Zone 2 and 0.65 in Zone 3.
0.75
0.650.40
0.40
0.400.40
19
30
0
10/13
U-factor Alternative to Meeting the Table 402.1.1/N1102.1 R-Value Requirements
CLIMATE ZONE
FENESTRATION U-FACTOR
SKYLIGHT U-FACTOR
CEILING U-FACTOR
FRAME WALL
U-FACTOR
MASS WALL
U-FACTORb
FLOOR U-FACTOR
BASEMENT WALL
U-FACTORd
CRAWL SPACE WALL
U-FACTORc 1 1.20 0.75 0.035 0.082 0.197 0.064 0.360 0.477 2 0.65 0.75 0.035 0.082 0.165 0.064 0.360 0.477 3 0.50 0.65 0.035 0.082 0.141 0.047 0.091c 0.136
4 except Marine
0.35 0.60 0.030 0.082 0.141 0.047 0.059 0.065
5 and Marine 4
0.35 0.60 0.030 0.057 0.082 0.033 0.059 0.065
6 0.35 0.60 0.026 0.057 0.060 0.033 0.050 0.065 7 and 8 0.35 0.60 0.026 0.057 0.057 0.028 0.050 0.065
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Table 402.1.3 (IECC) and N1102.2 (IRC)
a. Non-fenestration U-factors shall be obtained from measurement, calculation or an approved source.b. When more than half the insulation is on the interior, the mass wall U-factors shall be a maximum of 0.17 in Zone 1, 0.14 in Zone 2, 0.12 in Zone 3, 0.10 in Zone 4 except Marine, and the same as the frame wall U-factor in Marine Zone 4 and Zones 5 through 8.c. Basement wall U-factor of 0.360 in warm-humid locations as defined by Figure 301.1 and Table 301.2.
U-factor Calculation
U-factors Are To Be Calculated Based On ASHRAE Handbook of Fundamentals– Include
thermal bridging affects of framing
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Percent of wall with framing
Percent of wall without framing
0.10060.0572Total Unadjusted U-factors
9.9417.48Total Unadjusted R-values
0.170.17Outside Air Film
0.180.187/8” Stucco
5.005.001” Cellular Polyurethane
3.46-----2 X 4 @ 16” O.C.
----11.00R-11 Fiberglass Batt Insulation
0.450.451/2” Gypsum Board
0.680.68Inside Air Film
Frame R-valueCavity R-valueList of Components
Percent of wall with framing
Percent of wall without framing
Uo = (0.0572 X 0.85) + (0.1006 X 0.15) = 0.0637
0.10060.0572Total Unadjusted U-factors(1/R-value)
9.9417.48Total Unadjusted R-values
0.170.17Outside Air Film
0.180.187/8” Stucco
5.005.001” Cellular Polyurethane
3.46-----2 X 4 @ 16” O.C.
----11.00R-11 Fiberglass Batt Insulation
0.450.451/2” Gypsum Board
0.680.68Inside Air Film
Frame R-valueCavity R-valueList of Components
Total UA Alternative
• Allows Efficiency Trade-offs Between Building Assemblies– Whole building approach allowing portions
of the building to under comply if portions over comply with the code
– Based on Table 402.1.3/N1102.1.2 Equivalent U-factors
• Basis for US DOE REScheck software
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UA Alternative eliminates exceptions
Eliminates the following exceptions:– Opaque door, 24 ft2
– Fenestration U-factor, 15 ft2
– Fenestration SHGC, 15 ft2
– Ceiling tradeoff, R49 to R38 / R38 to R30
– Ceiling w/o attic space, R30, 500ft2
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Total UA AlternativeSample Calculation• UA = (Uw X Aw) + (Ug X Ag) + (Ud + Ad) + (Uf X Af) + (Ur x Ar)Where:
– UA = Total U-factor X Area for Whole Building– Uw = U-factor of Wall Assembly– Ug = U-factor of Glass Assembly– Ud = U-factor of Door Assembly– Uf = U-factor of Floor Assembly– Ur = U-factor of Roof Assembly– Aw = Area of Wall Assembly– Ag = Area of Glass Assembly– Ad = Area of Door Assembly– Af = Area of Floor Assembly– Ar = Area of Roof Assembly
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Fenestration U-factorGlazed Fenestration
Exemption - Up to 15 ft2 of glazed fenestration
Does not apply to U-factor approach
• Example Uses– Stained glass
windows– Glass block– Door side lites
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Glazed Fenestration SHGC
What is Solar Heat Gain Coefficient?– A simple way to explain SHGC is
in terms of a ratio; where 1 is the maximum amount of solar heat gain that can come through a window and 0 is the least amount. An SHGC of 0.40 then means that 40% of the available solar heat is coming through the window .
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Glazed Fenestration SHGC
How are fenestration products rated?– NFRC 200
• Default U-factors from Table 303.1.3(3) – IECC or N1101.5(3) - IRC
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Glazed Fenestration SHGC
SHGC Area Weighted Average
– An area weighted average (including skylights) may be used to meet the SHGC requirement.
Example:
Window 1 SHGC- 0.35 100 ft2
Window 2 SHGC- 0.50 50 ft2
Window 3 SHGC- 0.40 50 ft2 (100 ft2 X 0.35) + (50 ft2 X 0.50) + (50 ft2
X 0.40) = 200 ft2
Average SHGC of .40
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Fenestration U-Factor, UA Alternative
Special Rules– Maximum fenestration U-factor
• Area weighted average maximum vertical fenestration U-factor
– IECC – Zones 4 – 5: 0.48– IECC – Zones 6 – 8: 0.40– IRC – Zones 6 – 8: 0.35
• Thermally isolated sunroom maximum skylight U-factor
– IECC – Zones 4 – 8: 0.75– IRC – Zones 4 – 8: 0.75
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Fenestration U-factorU-factor Area Weighted Average may be used to meet the u-factor requirement.
Example:
Window 1 U- 0.35 100 ft2
Window 2 U- 0.50 50 ft2
Window 3 U- 0.40 50 ft2
(100 ft2 X 0.35) + (50 ft2 X 0.50) + (50 ft2 X 0.40) 200 ft2
=U-0.40 Average
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Fenestration U-factor
What is considered fenestration in Tables 402.1.1and N1102.1?Vertical windowsOpaque doorsGlazed doorsGlazed blockCombination
opaque/glazed doors
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Fenestration U-factor
How are fenestration products rated?
– NFRC 100
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U-Factor
Now:CZ2 u-0.65CZ3 u-0.50CZ4 u-0.35
Was:CZ2 u-0.75CZ3 u-0.65CZ4 u-0.40
Door U-Factor
All Doors are Considered Fenestration
• Must Meet Fenestration U-factor Requirement– Can exempt one
“side hinged” opaque door assembly up to 24 ft2 47
Courtesy Jeldwen Doors
Skylight U-Factor
What is a Skylight?– Installed at a slope of
15 degrees or more from vertical
• No Limit on Skylight Area
• NFRC 100• Default U-factors per
Table 303.1.3(1) – IECC, N1101.5(1) – IRC
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Wood Frame Wall R-Value
Walls: 50% above grade and Enclosing conditioned space, wood framed
IncludesBetween floor spandrelsPeripheral edges of floors,
roof and basement knee wallsDormer wallsGable end wallsWalls enclosing a mansard
roofSkylight shafts
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R-Value computation
How Do I Insulate to Meet the Requirements?– Install insulation
between framing– Install insulation
between framing and over the face of the stud (continuous)
– Insulation R-values can be added
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Wood Frame Wall R-Value
Structural Sheathing AllowanceR-5 where there is no structural sheathingIf structural sheathing covers > 25%,
supplement with R-2 insulating sheathing over structural sheathing
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Advanced Framing – Optimum Value Engineering
• Building codes allow for advanced wall framing• Insulated corners, two-stud corner• Ladder framing for interior walls• Increased insulation
• Single Top Plate• Insulated Headers (non bearing exterior
walls) Span requirements can dictate a full bearing header.
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Code Compliant Wall Insulation Installation
Batt Insulation Required to be Labeled on Pieces ≥ 12” Wide, or provide Certification Listing:
Insulation typeManufacturerR-value Installed (R-19 Marked if Compressed)Blown or Sprayed Insulation (Fiberglass or Cellulose)R-valueInstalled densityCoverage area and number of bagsSprayed Polyurethane Foam (SPF)Installed thickness R-value
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Ceiling R-value
Ceiling R-value Requirements Based on Ceiling Assembly Type– Ceilings with attic spaces– Ceilings without attic spaces
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Ceiling R-value - Ceilings With Attic Spaces
Options for meeting requirements
– Standard truss system – Install R-value of insulation to meet the requirements specified in Table 402.1.1/N1102.1
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Cold corners contribute to condensation and mold growth.
Possibility of ice dam formations.
Potential Cold Climate Issues:
Ceiling R-value - Ceilings With Attic Spaces
Options for meeting requirements Oversized Truss / Energy
Truss / Raised Heel Truss Substitute R- 30 for
R-38 Insulation Substitute R- 38 for
R-49 Insulation Goal – Provide full height,
uncompressed insulation over exterior wall plate at the eaves
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Baffling to preventinsulation from blocking ventilation
Raised Heel Truss
Baffling to preventinsulation from blocking ventilation
Ceiling R-value – Ceilings Without Attic Spaces
Can install minimum R-30 insulation in roof assemblies that require > R-30Only allowed in
assemblies with insufficient space to install greater than R-30
Only allowed in ceiling areas up to 500 ft2 or 20% whichever is less
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Conditioned Attics
• IRC recognizes conditioned attics (Chapter 8)• Sets requirements (e.g. vapor retarders, air-
impermeable insulation, application)• Recognizes interaction between
roofing materials and impermeableinsulation
• US Department of Energy (DOE) building guides
• http://www.eere.energy.gov/buildings/building_america/for_builders.html
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Steel Framed Assemblies
• Steel Frame Assemblies Must Meet the Requirements of Table 402.2.5-IECC or N1102.2.5 - IRC
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Floor R-Value
What Floors Types Are Covered? – Floors Over:
• Unconditioned space
• Vented crawlspace
• Unconditioned garage
• Outside air
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Code Compliant Raised Floor Insulation
• Insulation must fill the floor joist cavity from joist to joist and be in permanent contact with the subfloor
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Insulation Must FillFrom Joist to Joist
Section 403 - Systems
Section 403.1 - Controls • Each heating or cooling system shall have a
thermostat• For forced-air systems, a programmable thermostat
is required, with a setback range of 55 ̊F to 85 ̊F, and initial programming of 70 ̊F (heating) and 78 ̊F (cooling)
• Heat pumps with supplementary electric heat shall have controls to prevent operation of the supplemental heat when the heat pump can meet the load.
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Section 403.2.1 - Ducts Insulation
(Prescriptive)Heating and Cooling Equipment
– Duct Insulation • Supply ducts in attics shall
be insulated to an R-8• All other ducts (returns) shall
be insulated to an R-6• Ducts inside the building
thermal envelope are exempt
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Section 4.3.3 – Mechanical System Piping Insulation
• (Minimum) R-3 for piping carrying fluids above
105 ̊F or below 55 ̊F.
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Section 403.2.1 – Duct Sealing • Ducts, air handlers, filters, cavities used as ducts
to be sealed per IRC M1601.4.1 • Duct tightness to be verified by Postconstruction test – leakage to outdoors @
(max ) 8 cfm/100sf(25Pa) of conditioned space, or Rough-in test – total leakage @ (max) 6cfm/100sf(25PA) of conditioned spaceException – testing not required if air handler and
all ducts are located within conditioned space
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Building Envelope Mandatory Requirements
Air Leakage Controls– Goal is to limit infiltration– Limit both heat and moisture flow– Air sealant materials must allow for
differential expansion and contraction between dissimilar materials
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What Options are Available as an Air Sealant?
• Caulking• Gasketing• Weatherstripping• Sealed with an air barrier
material, suitable film or solid material
• Self sealing continuous materials - examples– Concrete– SIPS– ICF
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Air Sealing
• Required Sealing around Tub/Shower Enclosure and Attic Knee wall
• Recessed Lighting IC-Rated
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Section 402.4.1 Air LeakageThermal Envelope Requirements1. All joints, seams and penetrations2. Site-built windows, doors and skylights3. Between window and door assemblies
and framing4. Utility penetrations5. Dropped ceilings or chases 6. Knee walls7. Walls and ceilings separating a garage8. Behind tubs and showers on exterior
walls9. Common walls between dwelling units10. Attic access openings.11. Rim joists junction12. Other sources of infiltration
402.4.2.1 Testing option. Building envelope tightness and insulation installation shall be considered acceptable when tested air leakage is less than 7 ACH when tested with a blower door at a pressure of 50 Pascal's. Testing shall occur after rough in and after installation of penetrations of the building envelope, including penetrations for utilities, plumbing, electrical, ventilation, and combustion appliances.
402.4.2 Air sealing and insulation. …shall be demonstrated to comply with one of the following options :
Air Sealing
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402.4.2.2 Visual inspection option: Building envelope tightness and insulation installation shall be considered acceptable when the items listed in Table 402.4.2, applicable to the method of construction, are field verified. Where required by the code official, an approved party independent from the installer of the insulation, shall inspect the air barrier and insulation.
Air Sealing
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Air barrier and thermal barrier
Ceiling / attic
Walls
Windows and doorsRim joists
Floors (including above garage and cantilevered floors)Crawlspace walls
Exterior thermal envelope insulation for framed walls is installed in substantial contact and continuous alignment with building envelope air barrier.Breaks or joints in the air barrier are filled or repaired.Air permeable insulation is not used as a sealing material.Air permeable insulation is inside of an air barrier.Air barrier in any dropped ceiling / soffit is substantially aligned with insulation and any gaps are sealed. Attic access (except unvented attic), knee wall door, or drop down stair is sealed. Corners and headers are insulated. Junction of foundation and sill plate is sealed. Space between window/door jambs and framing is sealed. Rim joists are insulated and include an air barrier.
Insulation is installed to maintain permanent contact with underside of subfloor decking.
Air barrier is installed at any exposed edge of insulation.
Insulation is permanently attached to walls. Exposed earth in unvented crawlspaces is covered with class I vapor retarder with overlapping joints taped.
COMPONENT CRITERIA
AIR BARRIER AND INSULATION INSPECTIONTable 402.4.2 - Air Sealing
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Shafts, penetrations
Narrow cavities
Garage separationRecessed lighting
Plumbing and Wiring
Shower/tub on ext. wall
Electrical / phone box on exterior wallsCommon wallHVAC register boots
Fireplace
Duct shafts, utility penetrations, knee walls, and flue shafts opening to exterior or unconditioned space are sealed. Batts in narrow cavities are cut to fit, or narrow cavities are filled by sprayed/blown insulation.
Air sealing is provided between the garage and conditioned spaces. Recessed light fixtures are airtight, IC rated, and sealed to drywall. Exception--fixtures in conditioned space. Insulation is placed between outside and pipes. Batt insulation is cut to fit around wiring and plumbing, or sprayed/blown insulation extends behind piping and wiring.
Showers and tubs on exterior walls have insulation and an air barrier separating them from the exterior wall. Air barrier extends behind boxes or an air sealed type boxes are installed.
Air barrier is installed in common wall between dwelling units. HVAC register boots that penetrate building envelope are sealed to subfloor or drywall. Fireplace walls include an air barrier.
COMPONENT CRITERIA
AIR BARRIER AND INSULATION INSPECTIONTable 402.4.2 - Air Sealing
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Air Sealing
Recessed Lighting Fixtures 3 Options:– IC-Rated and meeting
ASTM E 283 ≤ 2.0 CFM leakage
– Sealed with a gasket or caulk between the housing and interior wall or ceiling surface.
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Systems Mandatory Requirements
Systems Include• Heating and
cooling systems• Circulating water
heating systems• Snow melt controls• Pool heaters and
covers
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Systems Mandatory Requirements
• Heating and Cooling Equipment– System sealing is
required including:• Ducts• Air handlers• Filter boxes• Building cavities
used as ducts
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Systems Mandatory RequirementsHeating and Cooling Equipment
Duct Sealing Section 403.2.2 IECC and M1601.4.1 IRC
• Can seal with tapes, mastics, gasketing and other approved closure devices
• Rigid fibrous glass ducts– Pressure sensitive tapes UL 181
A “181 A-P”– Mastic UL 181 A “181 A-M”– Heat sensitive tape UL 181 A
“181 A-H”• Flexible air duct
– Pressure sensitive tape UL 181B “181B-FX”
– Mastic UL 181B “181B-M”
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1. Post construction test: Leakage to outdoors shall be < 8 cfm per 100 ft2 of conditioned floor area
or, < 12 cfm per 100 ft2 of conditioned floor area across entire system
2. Rough-in test: Total leakage shall be < 6 cfm per 100 ft2 of conditioned floor area, at 25 Pa across rough system. If air handler not installed at test, then test at 4 cfm per 100 ft2 of conditioned floor area
3. Exception: Duct tightness testing is not required if air handler and ALL ducts are located within the conditioned space.
403.2.2 All ducts, air handlers, filter boxes and building cavities used as ducts shall be sealed. :
Systems Mandatory RequirementsDucts - Sealing
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Systems Requirements
• Heating and Cooling Equipment– Each separate space
conditioning system shall have a control
– Special thermostat for heat pump systems
– R-2 for piping carrying fluids > 105 ˚F or < 55˚F
– Outdoor air intakes or exhausts shall have dampers
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Initially programmed with
heating temperature set point no higher than 70oF and a
cooling temperature set point no lower
than 78oF
Systems Mandatory Requirements
• Heating and cooling equipment shall be sized in accordance with ACCA Manual J (IRC M1401.3) – or approved method– Outdoor design temperatures
per ACCA Manual S– Indoor design temperatures
• ≤ 72 ˚F Heating• ≥ 75 ˚F Cooling
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Systems Mandatory Requirements
• Water Heating– Circulating hot
water system piping to be insulated to an R-2
– Ability to switch the system off when not in use
• Manual switch• Automatic switch
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Section 403.5 – Mechanical Ventilation
• Outdoor air intakes and exhausts shall have gravity or automatic dampers that close when the system is not in operation.
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Section 403.6 – Equipment Sizing
• Equipment to be sized in accordance with
IRC M1401.3 – ACCA Manual S with loads calculated per ACCA Manual J
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Section 403.7 – Systems Serving Multiple Dwelling Units
• Such systems shall comply with Sec 503 and 504 (Commercial) instead of 403.
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Section 403.8 – Snow Melt Controls
• Such systems shall be provided with automatic controls to shut off the system when pavement temperature is above 50 ̊F, and with auto or manual controls to shutoff the systems when outdoor temperature is above 40 ̊F.
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Section 403.0 – Pools
• Pool heaters – All pool heaters shall be provided with a readily accessible shutoff switch, Gas-fired heaters shall not have continuously burning pilots.
• Pool heaters and pumps shall be provided with programmable shutoff switches, except where pumps are required to operate solar or waste heat recovery systems.
• Heated pools shall be provided with vapor retardant covers. Pools heated to more than 90 ̊F shall have R-12 covers, except for pools deriving more than 60% of their energy from a solar or site-recovered source.
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Section 404 - Lighting
• High-Efficacy LampsT-8 or smaller60 lumens per watt over 40 watts50 lumens per watt over 15 watts to 40
watts40 lumens per watt 15 watts or less
– 50% of lamps
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Total UA Alternative - REScheck
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Simulated Performance
• Simulates the Energy Use of a Proposed Residence and Determines the Cost to Operate Annually
• Most Flexible Energy Code Compliance Approach, Accounts for:
• House tightness• Heating and cooling efficiency• Service water heating efficiency• Building orientation• Thermal mass• Duct leakage
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Simulated Performance
<
ProposedDesign
Energy Estimation
Tool
BuildingComplies
When The:
Energy Costof
Proposed
Energy useof Standard
StandardDesign
<
ProposedDesign
Energy Estimation
Tool
BuildingComplies
When The:
Energy Costof
Proposed
Energy useof Standard
StandardDesign
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Simulated Performance
Required Documentation– Compliance report
• Address of residence• Inspection checklist• Compliance author• Name and version of
compliance software
Optional documentation– Standard reference
and proposed design documentation
– Certification showing building component characteristics of proposed design
• Must be signed by the builder
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HVAC trade-off eliminated in 2009 IECC
Energy Code Compliance Process
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Mandatory Provisions
Prescriptive
Envelope Section 402
Envelope ProvisionsSection 402.2, 402.3.3 thru 402.3.6 & 402.5 (As Applies)
Simulated Performance Section 405Insulation
Requirements Fenestration
Section 403.2.1 & 404.1
Table 402.1.3
Section 402.3.1 & 402.3.2 (Trade-Off)
Section 402.1.1 & 402.1.2 (Tabular)
Section 402.1.3 & 402.1.4 (Trade-Off)
Project Complies
OR OR
Above Code Programs
Allows National, State andLocal Energy EfficiencyPrograms as Alternatives to Complying with the 2009 IECC or IRC
– Program must exceed the current energy code– Must be approved by the code official or the
authority having jurisdiction– Must meet mandatory requirements
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Additional Resources
Websites
• International Codes Council www.iccsafe.org/• US Department of Energy www.energycodes.gov/• National Fenestration Rating Council, Inc www.nfrc.org• New Buildings Institute www.newbuildings.org• United State Department of Energy, Building Codes Program• Submit a question at Ask an Energy Codes Expert• Locate compliance software - visit U.S. Department of
Energy's Building Energy Software Tools Directory for more information.
• International Codes Council (ICC), Code clarification for ICC Members - 1-888-ICC-SAFE (1-888-422-7233)
• Simplyinsulate.com• CONTACT INFO: Forrest Fielder, [email protected]
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