Envelope construction, insulation, fenestration and thermal performance

Grounded in the retrieved California Energy Code — click a citation to read the verbatim passage:

• § 100.1 High relevance — show source text

  As defined in Section 100.1, light mass walls are walls with a heat capacity of at least 7.0 Btu/ft2-°F and less than 15.0 Btu/ft2-°F. Heavy mass walls are walls with a heat capacity
  of at least 15.0 Btu/ft2-°F.
  2. Glazed doors applies to both site-built and to factory-assembled glazed doors.|Notes:
  1. As defined in Section 100.1, light mass walls are walls with a heat capacity of at least 7.0 Btu/ft2-°F and less than 15.0 Btu/ft2-°F. Heavy mass walls are walls with a heat capacity
  of at least 15.0 Btu/ft2-°F.
  2. Glazed doors applies to both site-built and to factory-assembled glazed doors.|Notes:
  1. As defined in Section 100.1, light mass walls are walls with a heat capacity of at least 7.0 Btu/ft2-°F and less than 15.0 Btu/ft2-°F. Heavy mass walls are walls with a heat capacity
  of at least 15.0 Btu/ft2-°F.
  2. Glazed doors applies to both site-built and to factory-assembled glazed doors.|

  2025 CALIFORNIA ENERGY CODE 111

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES—PERFORMANCE AND PRESCRIPTIVE

  COMPLIANCE APPROACHES FOR ACHIEVING ENERGY EFFICIENCY

  TABLE 140.3-D—PRESCRIPTIVE ENVELOPE CRITERIA FOR RELOCATABLE PUBLIC SCHOOL BUILDINGS FOR USE IN ALL CLIMATE ZONES	Col2	Col3
  ENVELOPE FEATURE	CRITERIA	VALUE
  Roofs and Ceilings – Metal Buildings	Maximum U-factor	0.038
  Roofs and Ceilings – Nonmetal Buildings	Maximum U-factor	0.028
  Walls – Wood-framed buildings	Maximum U-factor	0.038
  Walls – Metal-framed buildings	Maximum U-factor	0.055
  Walls – Metal buildings	Maximum U-factor	0.053
  Walls – Mass/7.0 ≤ HC	Maximum U-factor	0.138
  Walls – All Other Walls	Maximum U-factor	0.038
  Floors and Soffits – Raised Mass	Maximum U-factor	0.058
  Floors and Soffits – Other	Maximum U-factor	0.039
  Roofing Products – Low-Sloped	Aged Solar Reflectance	0.63
  Roofing Products – Low-Sloped	Thermal Emittance	0.75
  Roofing Products – Steep-Sloped	Aged Solar Reflectance	0.25
  Roofing Products – Steep-Sloped	Thermal Emittance	0.80
  Fenestration – Fixed Windows	Maximum U-factor	0.34
  Fenestration – Fixed Windows	Maximum RSHGC	0.22
  Fenestration – Fixed Windows	Minimum VT	0.42
  Fenestration – Operable Windows	Maximum U-factor	0.46
  Fenestration – Operable Windows	Maximum RSHGC	0.

• § 150.1 High relevance — show source text

  i. Framed exterior walls shall be insulated such that the exterior wall has an assembly U -factor equal to or less than that shown in Table 150.1-A. The U -factors shown are maximum U -factors for the exterior wall assembly. ii. Mass walls above grade and below grade shall be insulated such that the wall has an assembly U -factor equal to or less than that shown in Table 150.1-A, or walls shall be insulated with continuous insulation that has an R value equal to or greater than that shown in Table 150.1-A. “Interior” denotes continuous insulation installed on the inside surface of the wall, and “exterior” denotes continuous insulation installed on the outside surface of the wall.

  iii. Other unframed exterior walls, excluding mass walls, shall meet the requirements for framed walls shown in Table 150.1-A.

  C. Raised floors shall be insulated such that the floor assembly has an assembly U -factor equal to or less than shown in Table 150.1-A, or shall be insulated between wood framing with insulation having an R- value equal to or greater than that shown in Table 150.1-A.

  Exception to Section 150.1(c)1C: Raised-floor insulation may be omitted if the foundation walls are insulated to meet the wall insulation minimums shown in Table 150.1-A, and a vapor retarder is placed over the entire floor of the crawl space, and the vents are fitted with automatically operated louvers, and the requirements of Reference Residential Appendix RA4.5.1 are met. D. Slab floor perimeter insulation shall be installed with a U -factor equal to or less than, or R -value equal to or greater than, shown in Table 150.1-A. The minimum depth of concrete-slab floor perimeter insulation shall be 16 inches or the depth of the footing of the building, whichever is less. Exception to Section 150.1(c)1: The insulation requirements of Table 150.1-A may also be met by ceiling, roof deck, wall, or floor assemblies that meet the required maximum U -factors using a U -factor calculation method that considers the thermal effects of all elements of the assembly and is approved by the executive director. E. All buildings shall comply with the quality insulation installation (QII) requirements shown in Table 150.1-A. When QII is required, insulation installation shall meet the criteria specified in Reference Appendix RA3.5.

  178 2025 CALIFORNIA ENERGY CODE

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  SINGLE-FAMILY RESIDENTIAL BUILDINGS—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES

  2. Radiant barrier. A radiant barrier required in Table 150.1-A shall meet the requirements specified in Section 110.8(j) and shall meet the installation criteria specified in the Reference Residential Appendix RA4.

  3. Fenestration.

  A. Installed fenestration products, including glazed doors, shall have an area weighted average U -factor and Solar Heat Gain Coefficient (SHGC) meeting the applicable fenestration value in Table 150.1-A and shall be determined in accordance with Sections 110.6(a)2 and 110.6(a)3. Exception 1 to Section 150.1(c)3A: New dwelling units with a conditioned floor area of 500 square feet or less in Climate Zone 5 may comply with a maximum U -factor of 0.30.

• § 1404.3.1 High relevance — show source text

  The exterior continuous insulation shall be permitted to serve as the vapor control layer where, at its
  installed thickness or with a facer on its interior face, the exterior continuous insulation is a Class I or II vapor retarder.
  c. The requirements of this table apply only to continuous insulation used to control moisture in order to allow walls without a Class I, II or III interior vapor retarder. The insula-
  tion materials used to satisfy this option also contribute to but do not supersede the_building_ thermal envelope requirements of the_California Energy Code_.|a. The total insulating value of materials to the interior side of the exterior continuous insulation, including any cavity insulation, shall not exceed R-5. Where the_R_-value of
  materials to the interior side of the exterior continuous insulation exceeds R-5, an_approved_ design shall be required.
  b. A water vapor control material layer having a permeance of not greater than 1 perm in accordance with ASTM E96, Procedure A (dry cup) shall be placed on the exterior side
  of the wall and to the interior side of the exterior continuous insulation. The exterior continuous insulation shall be permitted to serve as the vapor control layer where, at its
  installed thickness or with a facer on its interior face, the exterior continuous insulation is a Class I or II vapor retarder.
  c. The requirements of this table apply only to continuous insulation used to control moisture in order to allow walls without a Class I, II or III interior vapor retarder. The insula-
  tion materials used to satisfy this option also contribute to but do not supersede the_building_ thermal envelope requirements of the_California Energy Code_.|

  �

  EXTERIOR WALLS

  1404.3.1 Spray foam plastic insulation for moisture control with Class II and III vapor retarders. For purposes of compliance with Tables 1404.3(3) and 1404.3(4), spray foam with a maximum permeance of 1.5 perms at the installed thickness applied to the interior side of wood structural panels, fiberboard, insulating sheathing or gypsum shall be deemed to meet the continuous insulation moisture control requirement in accordance with one of the following conditions:

  1. The spray foam R -value meets or exceeds the specified continuous insulation R-value.
  2. The combined R -value of the spray foam and continuous insulation is equal to or greater than the specified continuous insulation R -value.

  1404.3.2 Vapor retarder installation. Vapor retarders shall be installed in accordance with the manufacturer’s instructions or an approved design. Where a vapor retarder also functions as a component of a continuous air barrier, the vapor retarder shall be installed as an air barrier in accordance with the California Energy Code . 1404.3.3 California Energy Code and International Energy Conservation Code Climate Zones. The IECC climate zones used by this section differ from those used by the California Energy Code to determine applicability of energy efficiency measures. Comparison of IECC and California Energy Code climate zones is shown in Chapter 12, Table 1202.3.1. 1404.4 Flashing. Flashing shall be installed in such a manner so as to prevent moisture from entering the exterior wall or to redirect that moisture to the surface of the exterior wall covering or to a water-resistive barrier complying with Section 1403.2 and that is part of a means of drainage complying with Section 1402.2.

• § 4.3.1 High relevance — show source text

  Use Reference Joint Appendices JA4 Table 4.3.1, 4.3.1(a), or Table 4.3.4 to determine alternative insu-
  lation products to be less than or equal to the required maximum U-factor.
  4. Mass wall has a heat capacity greater than or equal to 7.0 Btu/h-ft2.
  5. Product must be certified to meet the North American Fenestration Standard/Specification for an Architectural Window (AW).
  6. Glazed doors must meet the fenestration requirements.
  7. Requirements apply to doors included in the curtain wall/storefront construction assembly.
  8. If using_F_-factor to comply, use Reference Joint Appendices JA4, Table 4.4.7 to determine alternate depth and R-value to be less than or equal to the required maximum_F_-
  factor.
  9. Option B meets §170.2(a)1Bii.
  10. Option C meets §170.2(a)1BIiii.
  11. Option D meets §170.2(a)1Biv.|1. Install the specified_R_-value with an airspace present between the roofing and the roof deck. Such as standard installation of concrete or clay tile.
  2._ R_-values shown for below roof deck insulation are for wood-frame construction with insulation installed between the framing members. Alternatives including insulation
  above rafters or above roof deck shall comply with the performance standards.
  3. Assembly_U_-factors for exterior framed walls can be met with cavity insulation alone or with continuous insulation alone, or with both cavity and continuous insulation that
  results in an assembly_U_-factor equal to or less than the_U_-factor shown. Use Reference Joint Appendices JA4 Table 4.3.1, 4.3.1(a), or Table 4.3.4 to determine alternative insu-
  lation products to be less than or equal to the required maximum U-factor.
  4. Mass wall has a heat capacity greater than or equal to 7.0 Btu/h-ft2.
  5. Product must be certified to meet the North American Fenestration Standard/Specification for an Architectural Window (AW).
  6. Glazed doors must meet the fenestration requirements.
  7. Requirements apply to doors included in the curtain wall/storefront construction assembly.
  8. If using_F_-factor to comply, use Reference Joint Appendices JA4, Table 4.4.7 to determine alternate depth and R-value to be less than or equal to the required maximum_F_-
  factor.
  9. Option B meets §170.2(a)1Bii.
  10. Option C meets §170.2(a)1BIiii.
  11. Option D meets §170.2(a)1Biv.|

  242 2025 CALIFORNIA ENERGY CODE

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  MULTIFAMILY BUILDINGS—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES

  TABLE 170.2-B—SUPPLY FAN POWER ALLOWANCES (watts/cfm)	Col2	Col3	Col4	Col5	Col6	Col7
  	MULTI-ZONE VAV SYSTEMS ≤ **5,

• § 170.2 High relevance — show source text

  Exception 2 to Section 170.2(a)1A: Roof constructions with a weight of at least 25 lb/ft2 are not required to comply with the minimum requirements for solar reflectance and thermal emittance or SRI. B. Roof insulation. roofs shall have an overall assembly U -factor no greater than the applicable value in Table 170.2-A, meeting i, ii, iii or iv below. Where required by Sections 110.8 and 160.1(a), insulation shall be placed in direct contact with a continuous roof or drywall ceiling. i. Option A: Reserved. ii. Option B: A minimum R -value of insulation installed between the roof rafters in contact with the roof deck and an additional layer of ceiling insulation located between the attic and the conditioned space when meeting Section 170.2(c)3Biia; or iii. Option C: A minimum R -value of ceiling insulation located between the attic and the conditioned space when meeting Section 170.2(c)3Biib. iv. Option D: A minimum U -factor for roof assemblies above conditioned space without attic space. C. Radiant barrier. A radiant barrier required in Table 170.2-A shall meet the requirements specified in Section 110.8(j), and shall meet the installation criteria specified in Reference Residential Appendix RA4 .

  2. Wall insulation.

  A. Exterior walls shall have an overall assembly U -factor no greater than the applicable value in Table 170.2-A. B. Demising walls shall meet the requirements of Section 160.1(b)7. Vertical windows in demising walls between conditioned and unconditioned spaces shall have an area-weighted average U -factor no greater than the applicable value in Table 170.2-A.

  3. Fenestration.

  A. Vertical fenestration and glazed doors in exterior walls shall comply with Subsections i, ii and iii:

  238 2025 CALIFORNIA ENERGY CODE

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  MULTIFAMILY BUILDINGS—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES

  i. Percent fenestration area shall be limited in accordance with the applicable requirements of a and b below: a. A total fenestration area no greater than 20 percent of the conditioned floor area; and b. A total fenestration area no greater than 40 percent of the gross exterior wall area. NOTE: Demising walls are not exterior walls, and therefore demising wall area is not part of the gross exterior wall area, and fenestration in demising walls is not part of the fenestration area limitation. ii. Fenestration properties. Installed fenestration products, including glazed doors, shall have an area-weighted average U -factor, relative solar heat gain coefficient (RSHGC) and visible transmittance (VT) meeting the applicable fenestration values in Table 170.2-A and shall be determined in accordance with Sections 110.6(a)2 and 110.6(a)3. Vertical fenestration in demising walls between conditioned and unconditioned spaces is only required to comply with the area-weighted average U -factor requirement in Table 170.2-A. Exception 1 to Section 170.2(a)3Aii: For each dwelling unit, up to 3 square feet of new glazing area installed in doors shall not be required to meet the U -factor and RSHGC requirements of Table 170.2-A.

• § 0.269. High relevance — show source text

  (c) Floor and soffit insulation. The opaque portions of floors and soffits that separate conditioned spaces from unconditioned spaces or ambient air shall meet the applicable requirements of Items 1 through 3 below:

  1. Raised mass floors shall have a minimum of 3 inches of lightweight concrete over a metal deck or the area-weighted average U- factor of the floor assembly shall not exceed 0.269.

  2025 CALIFORNIA ENERGY CODE 199

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  MULTIFAMILY BUILDINGS—MANDATORY REQUIREMENTS

  2. Raised wood floor shall have an overall assembly U- factor not exceeding 0.037. In a wood framed assembly, compliance with the U- factor may be demonstrated by installing insulation with an R- value of 19 or greater.
  3. Other floors—The area-weighted average U- factor of the floor assembly shall not exceed 0.071.
  4. Heated slab on grade floor—A heated slab on grade floor shall be insulated to meet the requirements of Section 110.8(g). Exception to Section 160.1(c): A building with a controlled ventilation or unvented crawl space may omit raised floor insulation if all of the following are met: A. The foundation walls are insulated to meet the wall insulation minimums as shown in Table 170.2-A; and

  B. A Class I or Class II vapor retarder is placed over the entire floor of the crawl space; and C. Vents between the crawl space and outside air are fitted with automatically operated louvers that are temperature actuated; and

  D. The requirements in Reference Residential Appendix RA4.5.1.

  (d) Vapor retarder.

  1. In Climate Zones 1–16, the earth floor of unvented crawl space shall be covered with a Class I or Class II vapor retarder. This requirement shall also apply to controlled ventilation crawl space for buildings complying with the Exception to Section 160.1(c).

  2. In Climate Zones 14 and 16, a Class I or Class II vapor retarder shall be installed on the conditioned space side of all insulation in all exterior walls, vented attics and unvented attics with air-permeable insulation.

  (e) Fenestration products. Fenestration separating conditioned space from unconditioned space or outdoors shall meet the requirements of either Item 1 or 2 below:

  1. Fenestration, including skylight products, must have a maximum U- factor of 0.58. Exception 1 to Section 160.1(e)1: Up to 0.5 percent of the conditioned floor area is not required to comply with the maximum U- factor requirement. Exception 2 to Section 160.1(e)1: For dual-glazed greenhouse or garden windows, up to 30 square feet of fenestration area per dwelling unit is not required to comply with the maximum U- factor requirement.
  2. The area-weighted average U- factor of all fenestration, including skylight products, shall not exceed 0.58.

  Exception to Section 160.1(e): Fenestration installed in buildings meeting Part 7 of the California Building Code, California Wild- land-Urban Interface Code, where the building is located in Fire Hazard Severity Zones or Wildland-Urban Interface (WUI) Fire Areas as designated by the local enforcement agency.

  (f) **Installation of fireplaces, decorative gas appliances and gas logs.

• § 14-7 High relevance — show source text

  Vented cladding shall include vinyl lap siding, polypropylene, horizontal aluminum siding, brick veneer with airspace as specified in this code, rainscreen systems and other
  approved vented claddings.
  b. The requirements in this table apply only to insulation used to control moisture in order to permit the use of Class III vapor retarders. The insulation materials used to satisfy
  this option also contribute to but do not supersede the building thermal envelope requirements of the_California Energy Code_.|

  2025 CALIFORNIA BUILDING CODE 14-7

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  TABLE 1404.3(4)—CONTINUOUS INSULATION WITH A CLASS I OR II RESPONSIVE VAPOR RETARDER	Col2
  CLIMATE ZONE	PERMITTED CONDITIONSa
  3	Continuous insulation with_R_-value ≥ R-2
  4, 5, 6	Continuous insulation with_R_-value ≥ R-3 over 2 × 4 wall Continuous insulation with_R_-value ≥ R-5 over 2 × 6 wall
  7	Continuous insulation with_R_-value ≥ R-5 over 2 × 4 wall Continuous insulation with_R_-value ≥ R-7.5 over 2 × 6 wall
  8	Continuous insulation with_R_-value ≥ R-7.5 over 2 × 4 wall Continuous insulation with_R_-value ≥ R-10 over 2 × 6 wall
  a. The requirements in this table apply only to insulation used to control moisture in order to permit the use of Class I or II vapor retarders. The insulation materials used to satisfy this option also contribute to but do not supersede the building thermal envelope requirements of the_California Energy Code_.	a. The requirements in this table apply only to insulation used to control moisture in order to permit the use of Class I or II vapor retarders. The insulation materials used to satisfy this option also contribute to but do not supersede the building thermal envelope requirements of the_California Energy Code_.

  TABLE 1404.3(5)—CONTINUOUS INSULATION ON WALLS WITHOUT A CLASS I, II, OR III INTERIOR VAPOR RETARDERa	Col2
  CLIMATE ZONE	PERMITTED CONDITIONSb,c
  4	Continuous insulation with_R_-value ≥ 4.5
  5	Continuous insulation with_R_-value ≥ 6.5
  6	Continuous insulation with_R_-value ≥ 8.5
  7	Continuous insulation with_R_-value ≥ 11.5
  8	Continuous insulation with_R_-value ≥ 14
  a. The total insulating value of materials to the interior side of the exterior continuous insulation, including any cavity insulation, shall not exceed R-5. Where the_R_-value of materials to the interior side of the exterior continuous insulation exceeds R-5, an_approved_ design shall be required. b. A water vapor control material layer having a permeance of not greater than 1 perm in accordance with ASTM E96, Procedure A (dry cup) shall be placed on the exterior side of the wall and to the interior side of the exterior continuous insulation. The exterior continuous insulation shall be permitted to serve as the vapor control layer where, at its installed thickness or with a facer on its interior face, the exterior continuous insulation is a Class I or II vapor retarder. c.

• § 1404.3 High relevance — show source text

  The requirements in this table apply only to insulation used to control moisture in order to permit the use of Class I or II vapor retarders. The insulation materials used to
  satisfy this option also contribute to but do not supersede the building thermal envelope requirements of the_California Energy Code_.|

  TABLE 1404.3(5)—CONTINUOUS INSULATION ON WALLS WITHOUT A CLASS I, II, OR III INTERIOR VAPOR RETARDERa	Col2
  CLIMATE ZONE	PERMITTED CONDITIONSb,c
  4	Continuous insulation with_R_-value ≥ 4.5
  5	Continuous insulation with_R_-value ≥ 6.5
  6	Continuous insulation with_R_-value ≥ 8.5
  7	Continuous insulation with_R_-value ≥ 11.5
  8	Continuous insulation with_R_-value ≥ 14
  a. The total insulating value of materials to the interior side of the exterior continuous insulation, including any cavity insulation, shall not exceed R-5. Where the_R_-value of materials to the interior side of the exterior continuous insulation exceeds R-5, an_approved_ design shall be required. b. A water vapor control material layer having a permeance of not greater than 1 perm in accordance with ASTM E96, Procedure A (dry cup) shall be placed on the exterior side of the wall and to the interior side of the exterior continuous insulation. The exterior continuous insulation shall be permitted to serve as the vapor control layer where, at its installed thickness or with a facer on its interior face, the exterior continuous insulation is a Class I or II vapor retarder. c. The requirements of this table apply only to continuous insulation used to control moisture in order to allow walls without a Class I, II or III interior vapor retarder. The insula- tion materials used to satisfy this option also contribute to but do not supersede the_building_ thermal envelope requirements of the_California Energy Code_.	a. The total insulating value of materials to the interior side of the exterior continuous insulation, including any cavity insulation, shall not exceed R-5. Where the_R_-value of materials to the interior side of the exterior continuous insulation exceeds R-5, an_approved_ design shall be required. b. A water vapor control material layer having a permeance of not greater than 1 perm in accordance with ASTM E96, Procedure A (dry cup) shall be placed on the exterior side of the wall and to the interior side of the exterior continuous insulation. The exterior continuous insulation shall be permitted to serve as the vapor control layer where, at its installed thickness or with a facer on its interior face, the exterior continuous insulation is a Class I or II vapor retarder. c. The requirements of this table apply only to continuous insulation used to control moisture in order to allow walls without a Class I, II or III interior vapor retarder. The insula- tion materials used to satisfy this option also contribute to but do not supersede the_building_ thermal envelope requirements of the_California Energy Code_.

  �

  EXTERIOR WALLS

• § 150.1 High relevance — show source text

  The minimum depth of concrete-slab floor perimeter insulation shall be 16 inches or the depth of the footing of the building, whichever is less. Exception to Section 150.1(c)1: The insulation requirements of Table 150.1-A may also be met by ceiling, roof deck, wall, or floor assemblies that meet the required maximum U -factors using a U -factor calculation method that considers the thermal effects of all elements of the assembly and is approved by the executive director. E. All buildings shall comply with the quality insulation installation (QII) requirements shown in Table 150.1-A. When QII is required, insulation installation shall meet the criteria specified in Reference Appendix RA3.5.

  178 2025 CALIFORNIA ENERGY CODE

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  SINGLE-FAMILY RESIDENTIAL BUILDINGS—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES

  2. Radiant barrier. A radiant barrier required in Table 150.1-A shall meet the requirements specified in Section 110.8(j) and shall meet the installation criteria specified in the Reference Residential Appendix RA4.

  3. Fenestration.

  A. Installed fenestration products, including glazed doors, shall have an area weighted average U -factor and Solar Heat Gain Coefficient (SHGC) meeting the applicable fenestration value in Table 150.1-A and shall be determined in accordance with Sections 110.6(a)2 and 110.6(a)3. Exception 1 to Section 150.1(c)3A: New dwelling units with a conditioned floor area of 500 square feet or less in Climate Zone 5 may comply with a maximum U -factor of 0.30. Exception 2 to Section 150.1(c)3A: For each dwelling unit, up to 3 square feet of new glazing area installed in doors and up to 3 square feet of tubular skylights area with dual-pane diffusers shall not be required to meet the U -factor and SHGC requirements of Table 150.1-A. Exception 3 to Section 150.1(c)3A: In Climate Zones 2, 4, and 6 through 15, for each dwelling unit up to 16 square feet of skylight area with a maximum U -factor of 0.40 and a maximum SHGC of 0.30. In Climate Zones 1, 3, 5, and 16, there is no SHGC requirement. Exception 4 to Section 150.1(c)3A: For fenestration containing chromogenic type glazing:

  i. The lower-rated labeled U -factor and SHGC shall be used with automatic controls to modulate the amount of solar gain and light transmitted into the space in multiple steps in response to daylight levels or solar intensity; ii. Chromogenic glazing shall be considered separately from other fenestration; and iii. Area-weighted averaging with other fenestration that is not chromatic shall not be permitted and shall be determined in accordance with Section 110.6(a). Exception 5 to Section 150.1(c)3A: For dwelling units containing unrated site-built fenestration that meets the maximum area restriction, the U -factor and SHGC can be determined in accordance with the Nonresidential Reference Appendix NA6 or use default values in Table 110.6-A and Table 110.6-B.

• § 7-8 High relevance — show source text

  The insulation materials used to satisfy
  this option also contribute to but do not supersede the thermal envelope requirements of Chapter 11.|

  7-8 2025 CALIFORNIA RESIDENTIAL CODE

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  WALL COVERING

  TABLE R702.7(4)—CONTINUOUS INSULATION WITH CLASS I OR II RESPONSIVE VAPOR RETARDER	Col2
  CLIMATE ZONE	PERMITTED CONDITIONSa
  3	Continuous insulation with_R_-value ≥ 2.
  4, 5 and 6	Continuous insulation with_R_-value ≥ 3 over 2 × 4 wall. Continuous insulation with_R_-value ≥ 5 over 2 × 6 wall.
  7	Continuous insulation with_R_-value ≥ 5 over 2 × 4 wall. Continuous insulation with_R_-value ≥ 7.5 over 2 × 6 wall.
  8	Continuous insulation with_R_-value ≥ 7.5 over 2 × 4 wall. Continuous insulation with_R_-value ≥ 10 over 2 × 6 wall.
  a. The requirements in this table apply only to insulation used to control moisture in order to permit the use of Class II vapor retarders. The insulation materials used to satisfy this option also contribute to but do not supersede the thermal envelope requirements of Chapter 11.	a. The requirements in this table apply only to insulation used to control moisture in order to permit the use of Class II vapor retarders. The insulation materials used to satisfy this option also contribute to but do not supersede the thermal envelope requirements of Chapter 11.

  TABLE R702.7(5)—CONTINUOUS INSULATION ON WALLS WITHOUT A CLASS I, II OR III INTERIOR VAPOR RETARDERa	Col2
  CLIMATE ZONE	PERMITTED CONDITIONSb, c
  4	Continuous insulation with_R_-value ≥ 4.5
  5	Continuous insulation with_R_-value ≥ 6.5
  6	Continuous insulation with_R_-value ≥ 8.5
  7	Continuous insulation with_R_-value ≥ 11.5
  8	Continuous insulation with_R_-value ≥ 14
  a. The total insulating value of materials to the interior side of the exterior continuous insulation, including any cavity insulation, shall not exceed R-5. Where the R-value of materials to the interior side of the exterior continuous insulation exceeds R-5, an approved design shall be required. b. A water vapor control material layer having a permeance not greater than 1 perm in accordance with ASTM E96 Procedure A (dry cup) shall be placed on the exterior side of the wall and to the interior side of the exterior continuous insulation. The exterior continuous insulation shall be permitted to serve as the vapor control layer where, at its installed thickness or with a facer on its interior face, the exterior continuous insulation is a Class I or II vapor retarder. c. The requirements in this table apply only to insulation used to control moisture in order to allow walls without a Class I, II or III interior vapor retarder. The insulation materi- als used to satisfy this option also contribute to but do not supersede the thermal envelope requirements of the_California Energy Code_.	a. The total insulating value of materials to the interior side of the exterior continuous insulation, including any cavity insulation, shall not exceed R-5.

• § 205.1.1.4 High relevance — show source text

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  APPENDIX A6.1 — VOLUNTARY STANDARDS FOR HEALTH FACILITIES [OSHPD 1, 2 & 4]

  A6.205.1.1.4 Labeling. Fenestration products shall:

  1. Have a temporary label (or label certificate for site- built fenestration) meeting the requirements of Section 10111(a)1 of Title 24, Part 1 not to be removed before inspection by the enforcement agency, listing the certified U factor and SHGC and certifying that the air leakage requirements of Section A6.205.1.1.1 are met for each product line; and
  2. Have a permanent label (or label certificate for site-built fenestration) meeting the requirements of Section 10111(a)2 of Title 24, Part 1 if the product is rated using NFRC procedures.

  A6.205.1.1.5 Fenestration acceptance requirements. Before an occupancy permit is granted, site-built fenestration products in other than low-rise residential buildings shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified by the Reference Nonresidential Appendix NA7 of the California Energy Commission 2008 Building Energy Efficiency Standards for Residential and Nonresidential Buildings to ensure that site-built fenestration meet Standards requirements, including a matching label certificate for each product installed and be readily accessible at the project location. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the fenestration product meets the acceptance requirements.

  Exception: Fenestration products removed and reinstalled as part of a building alteration or addition.

  A6.205.1.2 Installation of field-fabricated fenestration and exterior doors. Field-fabricated fenestration and field-fabricated exterior doors may be installed only if the compliance documentation has demonstrated compliance for the installation using U factors from Table A6.205.1-A and SHGC values from Table A6.205.1-B. Field-fabricated fenestration and field-fabricated exterior doors shall be caulked between the fenestration products or exterior door and the building and shall be weatherstripped.

  Exception: Unframed glass doors and fire doors need not be weatherstripped or caulked.

  A6.205.2 Joints and other openings. Joints and other openings in the building envelope that are potential sources of air leakage shall be caulked, gasketed, weatherstripped or otherwise sealed to limit infiltration and exfiltration.

  A6.205.3 Insulation and roofing products.

  A6.205.3.1 Certification by manufacturers. Any insulation shall be certified by Department of Consumer Affairs, Bureau of Household Good and Services that the insulation conductive thermal performance is approved pursuant to the California Code of Regulations, Title 24, Part 12, Chapters 12-13, Article 3,“Standards for Insulating Material.”

  A6.205.3.2 Installation of urea formaldehyde foam insulation. Urea formaldehyde foam insulation may be applied or installed only if:

  1. It is installed in exterior side walls; and

  2. A four-mil-thick plastic polyethylene vapor barrier or equivalent plastic sheathing vapor barrier is installed between the urea formaldehyde foam insulation and the interior space in all applications.

• § 0.280. High relevance — show source text

  Spandrel panels and glass curtain walls. A minimum of R-4, or the area-weighted average U -factor of the wall assembly shall not exceed U-0.280. Exception to Section 141.0(b)1B: Light and heavy mass walls. C. Floor insulation. For the altered portion of raised floors that separate conditioned spaces from unconditioned spaces or ambient air shall meet the applicable requirements of Items 1 through 3 below:

  1. Raised framed floors. A minimum of R-11 insulation between framing members, or the area-weighted average U -factor of the floor assembly shall not exceed the U -factor of U-0.071.
  2. Raised mass floors in hotel/motel guest rooms. A minimum of R-6 insulation, or the area-weighted average U -factor of the floor assembly shall not exceed the U -factor of U-0.111.
  3. Raised mass floors in other occupancies. No minimum U -factor requirement. D . Fan energy index: New fan systems serving an existing building shall meet the requirements of Section 120.10. E. Exterior windows. Fenestration alterations other than repairs shall meet the following requirements:
  4. Vertical fenestration alterations. Where over 150 square feet of the entire building’s vertical fenestration is replaced, the maximum U -factor of the replaced units shall not exceed U-0.58.
  5. Added vertical fenestration. Where over 50 square feet of vertical fenestration is added, it shall meet the requirements of Section 120.7(d). Where 50 square feet or less of vertical fenestration is added, this requirement shall not apply.
  6. Prescriptive approach. The altered components of the envelope, or space conditioning, lighting, electrical power distribution and water heating systems, and any newly installed equipment serving the alteration, shall meet the applicable requirements of Sections 110.0 through 110.9, Sections 120.0 through 120.6, and Sections 120.9 through 130.5.

  Exception to Section 141.0(b)2: The requirements of Section 120.2(i) shall not apply to alterations of spaceconditioning systems or components. A. Fenestration alterations other than repair and those subject to Section 141.0(b)2 shall meet the requirements below: i. Vertical fenestration alterations shall meet the requirements in Table 141.0-A. ii. Added vertical fenestration shall meet the requirements of Table 140.3-B, C or D. iii. All altered or newly installed skylights shall meet the requirements of Table 140.3-B, C or D. Exception 1 to Section 141.0(b)2Ai: In an alteration, where 150 square feet or less of the entire building's vertical fenestration is replaced, RSHGC and VT requirements of Table 141.0-A shall not apply. Exception 2 to Section 141.0(b)2Aii: In an alteration, where 50 square feet or less of vertical fenestration is added, RSHGC and VT requirements of Table 140.3-B, C or D shall not apply. Exception 3 to Section 141.0(b)2Aiii: In an alteration, where 50 square feet or less of skylight is added, SHGC and VT requirements of Table 140.3-B, C or D shall not apply. NOTE: Glass replaced in an existing sash and frame or sashes replaced in an existing frame are considered repairs.