With ambitions to generate net zero energy buildings that make as much energy as they consume, the Title 24 energy codes target several building elements. A key target in the 2013 version are standards affecting residential fenestration. Effective July 1st, 2014, the energy code standards impacting fenestration products were updated in order to reduce energy loss and further enhance building performance. In the 2016 version, residential fenestration performance targets are mostly the same with the exception of a few minor updates to Air Leakage and U-factor.
Listed below are the two residential new construction compliance methods, along with required mandatory measures, that can be used to gain permit compliance. Updates made to the 2013 & 2016 NFRC energy performance identifiers for fenestration products are listed per the compliance method used in the tables below.
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Air Leakage
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Prescriptive
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Performance
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Mandatory Measures
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A minimum of 0.3 cfm/ft² is required for all manufactured
fenestration products when tested per NFRC 400
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A minimum of 0.3 cfm/ft² is required for all manufactured
fenestration products when tested per NFRC 400
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A minimum of 0.3 cfm/ft² is required for all manufactured fenestration
products when tested per NFRC 400
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U-Factor
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Use the applicable U-factor of 0.32 in all climate zones set forth in
Package A
or Table 150.1-A
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Rated by NFRC 100 or use the applicable default U-factor
set forth in TABLE 110.6-A
and must meet mandatory measures U-factor requirements
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Fenestration must have a maximum or weighted-average
U-factor of 0.58 or lower that separates conditioned space from unconditioned space
*Exception allows the greater of 10
ft2 or 0.5% of the conditioned floor area to exceed 0.58 U-factor
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Solar Heat Gain Coefficient (SHGC)
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Rated by NFRC 200 or use the maximum SHGC of 0.25 in all
climate zones except zones 1,3 & 5 per
Package A
or Table 150.1-A
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Rated by NFRC 200 or must use default values listed in
TABLE 110.6-B
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Not Applicable
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Visual Transmittance (VT)
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Rated by NFRC 200 and must be identified and labeled per
NFRC procedures
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Rated by NFRC 200 and must be identified and labeled per
NFRC procedures
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Not Applicable
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Wall-to-Windows Ratio
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Fenestration must meet prescriptive efficiency values and have
a maximum area of 20% of the window-to-wall ratio conditioned floor area (CFA)
per Package A
or Table 150.1-A
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Reducing fenestration area below the maximum allowed 20% of
the conditioned floor area (CFA) does not provide a credit. Furthermore, there
is a penalty for buildings that have a window area that exceeds 20% of CFA.
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Not Applicable
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Maximum West-Facing Fenestration
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The maximum west-facing fenestration area shall not exceed
5% of the conditioned floor area in all climate zones except zones 1, 3, &
5 per Package A
or Table 150.1-A
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Fenestration orientation is a recognized credit in the performance
approach and has an impact on energy use and peak electric demand
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Not Applicable
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Air Leakage
|
Prescriptive
|
Performance
|
Mandatory Measures
|
|
A minimum of 0.3 cfm/ft² is required for all manufactured
fenestration products when tested per NFRC 400
*New 2016 requirement includes pet doors
|
A minimum of 0.3 cfm/ft² is required for all manufactured
fenestration products when tested per NFRC 400
*New 2016 requirement includes pet doors
|
A minimum of 0.3 cfm/ft² is required for all manufactured fenestration
products when tested per NFRC 400
*New 2016 requirement includes pet doors
|
|
U-Factor
|
Use the applicable U-factor of 0.32 in all climate zones set forth in
Package A
or Table 150.1-A
|
Rated by NFRC 100 or use the applicable default U-factor
set forth in TABLE 110.6-A
and must meet mandatory measures U-factor requirements
|
Fenestration must have a maximum or weighted-average
U-factor of 0.58 or lower that separates conditioned space from unconditioned space
*Exception allows the greater of 10
ft2 or 0.5% of the conditioned floor area to exceed 0.58 U-factor
*New 2016 exception allows for 30sqft for dual glazed greenhouse windows
|
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Solar Heat Gain Coefficient (SHGC)
|
Rated by NFRC 200 or use the maximum SHGC of 0.25 in all
climate zones except zones 1, 3 & 5 per
Package A
or Table 150.1-A
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Rated by NFRC 200 or must use default values listed in
TABLE
110.6-B
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Not Applicable
|
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Visual Transmittance (VT)
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Rated by NFRC 200 and must be identified and labeled per
NFRC procedures
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Rated by NFRC 200 and must be identified and labeled per
NFRC procedures
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Not Applicable
|
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Wall-to-Windows Ratio
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Fenestration must meet prescriptive efficiency values and have
a maximum area of 20% of the window-to-wall ratio conditioned floor area (CFA)
per Package A
or Table 150.1-A
|
Reducing fenestration area below the maximum allowed 20% of
the conditioned floor area (CFA) does not provide a credit. Furthermore, there
is a penalty for buildings that have a window area that exceeds 20% of CFA.
|
Not Applicable
|
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Maximum West-Facing Fenestration
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The maximum west-facing fenestration area shall not exceed
5% of the conditioned floor area in all climate zones except zones 1, 3, &
5 per Package A
or Table 150.1-A
|
Fenestration orientation is a recognized credit in the performance
approach and has an impact on energy use and peak electric demand
|
Not Applicable
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