Title 24 · California Energy Code

Fenestration U‑factor, SHGC and area limits (prescriptive)

For homeowners: California’s energy code limits how much window area you can have and sets maximum heat‑loss (U‑factor) and solar heat gain (SHGC/RSHGC) values. For multifamily units, total glazing is usually limited to 20% of conditioned floor area and must meet area‑weighted U and SHGC limits; the code spells out how to use labeled ratings or default tables to prove compliance.

Last reviewed: July 6, 2026

What the code requires — short plain English

Installed fenestration (windows, glazed doors and skylights) must meet maximum U‑factor and SHGC (or RSHGC) limits and, for multifamily units, area limits and area‑weighted performance calculations. The prescriptive limits and how to calculate area‑weighted averages are controlled by § 150.1(c)3, § 170.2(a)3, and the methods for determining ratings are specified in § 110.6.

For most residential work you must (1) keep total fenestration within the percent‑of‑area limits, and (2) make the area‑weighted average U‑factor and SHGC/RSHGC of the installed fenestration meet the maxima listed in the applicable table.


Requirements in detail

Key defined terms (bolded on first use)

  • U‑factor — rate of heat transfer through fenestration (lower is better). § 110.6 governs how labeled or calculated U‑factors are determined.
  • SHGC — Solar Heat Gain Coefficient (fraction of solar radiation admitted). RSHGCrelative SHGC accounting for fixed shading (used in some multifamily calculations). § 170.2(a)3 and § 150.1(c)3 refer to SHGC/RSHGC requirements.
  • Area‑weighted average — the installed product performance (U, SHGC or RSHGC) averaged by each product’s glazing area as required by the code. See the referenced sections for the required calculation method. § 110.6(a)2 and § 110.6(a)3 are the methods cited by the fenestration sections.
  • Conditioned Floor Area (CFA) — used in percent‑area limits (see § 170.2(a)3(i)(a)).

Prescriptive decision table — common decision points and values

Decision dimension Typical prescriptive value(s) Code reference
Multifamily — maximum total fenestration (percent of CFA) 20% of conditioned floor area § 170.2(a)3(i)(a)
Multifamily — maximum total fenestration (percent of gross exterior wall) 40% of gross exterior wall area § 170.2(a)3(i)(b)
Area‑weighted U‑factor / RSHGC / VT (multifamily) Meet the values listed in Table 170.2‑A (area‑weighted) § 170.2(a)3(ii) and Table 170.2‑A
Single‑family / dwelling unit fenestration — area‑weighted U & SHGC Must meet values in Table 150.1‑A (see table for climate‑zone specifics) § 150.1(c)3(A) and Table 150.1‑A
Vertical fenestration — area‑weighted performance (example table entries) Typical area‑weighted maxima used by the code: Fixed window U ≤ 0.36; Operable window U ≤ 0.46; Max RSHGC: 0.25 (fixed) / 0.22 (operable) — see fenestration tables in the code document. See fenestration table (vertical, all climate zones)
Skylights (area‑weighted) Example: Max U ranges by type (glass curb 0.58, glass deck 0.46, plastic curb 0.88); Max SHGC 0.25 (glass) See skylight rows in fenestration tables
How to determine U/SHGC values Use labeled ratings or calculation methods in § 110.6; default values available in Table 110.6‑A/B for unrated products § 110.6 and Tables 110.6‑A/B

Note: Table numbers and values vary by occupancy and climate zone. Always confirm the numeric maxima from the applicable table for your project (Table 150.1‑A for the prescriptive single‑family criteria called out in § 150.1(c)3, Table 170.2‑A for multifamily § 170.2(a)3).

How area‑weighted averaging works (short)

  • Calculate each installed product’s glazing area and multiply by its rated U‑factor (or SHGC/RSHGC). Sum the products and divide by the total fenestration area to get the area‑weighted average. The code requires those averages to meet the maxima in the referenced tables. The code text points to § 110.6(a)2 and (a)3 for exactly how labeled and calculated values are used.

Exceptions & special cases

  • Small glazing exceptions: For each dwelling unit, up to 3 ft² of glazing in doors (and up to 3 ft² tubular skylights with dual‑pane diffusers) are not required to meet Table 150.1‑A limits. § 150.1(c)3 exceptions apply.
  • Skylight exception: For each dwelling unit, up to 16 ft² of skylight may be installed with a higher allowed maximum U and/or a specific SHGC cap depending on climate zone; see § 150.1(c)3(A) Exception 3 for climate‑zone specifics.
  • Chromogenic (dynamic) glazing: Chromogenic glazing is treated separately. Use the lower labeled U‑factor and SHGC and automatic controls as required; you may not area‑weight chromogenic glazing together with non‑chromogenic glazing (see exceptions in § 150.1(c)3(A) and § 170.2(a)3).
  • Unrated site‑built fenestration: Where installed fenestration is unrated but meets the maximum area restriction, U and SHGC can be determined using the Nonresidential Reference Appendix NA6 or default values in Table 110.6‑A/B. § 150.1(c)3(A) Exception 5 and § 170.2(a)3 Exception 3.
  • Demising walls: Fenestration in demising walls is not counted in gross exterior wall area for the 40% exterior wall limit, but vertical demising wall glazing must still meet the area‑weighted U‑factor requirement. § 170.2(a)3(i) and (ii).

Common mistakes

  • Treating RSHGC as the same as SHGC. RSHGC is a relative value used when an overhang or fixed shading is present and is specifically defined/calculated in § 170.2(a)3 (Equation 170.2‑A). Don’t confuse the two.
  • Forgetting to use area‑weighted averages — a single product that’s compliant on its own doesn’t make the whole installation compliant unless the overall area‑weighted average meets the table limits (the code repeatedly references area‑weighted calculations). § 150.1(c)3(A) and § 170.2(a)3(ii).
  • Counting demising‑wall glazing in the gross exterior wall area limit (demising walls are excluded). § 170.2(a)3(i) clarifies this.
  • Using unlabeled or manufacturer‑claimed values without confirming they meet the § 110.6 required method (labeled NFRC or approved calculation). Check § 110.6 and the default tables (110.6‑A/B) if using unrated products.

Worked example — multifamily dwelling unit (concrete numbers)

Scenario: A multifamily dwelling unit has 1,000 ft² conditioned floor area. Proposed new vertical fenestration (all exterior) totals 180 ft². The installer proposes:

  • 120 ft² of fixed glazing, rated U = 0.36, SHGC = 0.24
  • 60 ft² of operable windows, rated U = 0.46, SHGC = 0.20

Step 1 — Area limit check:

  • Total fenestration = 180 ft² = 18% of CFA (180 / 1000 = 0.18). The multifamily maximum is 20% of CFA per § 170.2(a)3(i)(a), so area is compliant.

Step 2 — Area‑weighted U‑factor:

  • Area‑weighted U = (120×0.36 + 60×0.46) / 180 = (43.2 + 27.6) / 180 = 70.8 / 180 = 0.393.
  • Compare the area‑weighted U to the applicable maximum in Table 170.2‑A (the code requires the area‑weighted U meet the table value). If Table 170.2‑A requires an area‑weighted U ≤ 0.36 for this product mix/occupancy, the proposed average 0.393 fails and must be improved (e.g., upgrade some units to lower‑U glazing or reduce glazing area). See § 170.2(a)3(ii) and Table 170.2‑A.

Step 3 — Area‑weighted SHGC/RSHGC (if applicable):

  • Area‑weighted SHGC = (120×0.24 + 60×0.20) / 180 = (28.8 + 12) / 180 = 40.8 / 180 = 0.227. For climate zones where RSHGC or SHGC limits apply, compare this area‑weighted value to Table 170.2‑A limits. § 170.2(a)3(iii) specifies RSHGC calculation rules if overhangs are present.

Notes: If chromogenic glazing or unrated site‑built windows are used, follow the special‑case rules in the exceptions (chromogenic uses the lower labeled values and is not area‑weighted with non‑chromogenic glazing; unrated can use Table 110.6 defaults or Appendix NA6).


Related provisions (quick list)

  • § 150.1(c)3 — Vertical fenestration U‑factor and SHGC requirements; Table 150.1‑A.
  • § 170.2(a)3 — Multifamily fenestration area limits and area‑weighted U, RSHGC, VT; Table 170.2‑A.
  • § 110.6 — Methods to determine U‑factor and SHGC; default values (Table 110.6‑A/B) for unrated products.
  • Table 150.1‑A — Prescriptive single‑family fenestration maxima (climate zone columns).
  • Table 170.2‑A — Prescriptive multifamily fenestration maxima (area‑weighted).

Code references

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

  • § 110.0 High relevance — show source text

    SINGLE-FAMILY RESIDENTIAL BUILDINGS—ADDITIONS AND ALTERATIONS TO EXISTING RESIDENTIAL BUILDINGS

    (b) Alterations. Alterations to existing single-family residential buildings or alterations in conjunction with a change in building occupancy to a single-family residential occupancy shall meet either Item 1 or 2 below.

    1. Prescriptive approach. The altered component and any newly installed equipment serving the alteration shall meet the applicable requirements of Sections 110.0 through 110.9, all applicable requirements of Sections 150.0(a) through (l), 150.0(m)1 through 150.0 (m)10, and 150.0(p) through (q); and A. Added fenestration. Alterations that add vertical fenestration and skylight area shall meet the total fenestration area and west facing fenestration area, U -factor, and solar heat gain coefficient requirements of Section 150.1(c)3A and Table 150.1-A.

    Exception 1 to Section 150.2(b)1A: Alterations that increase fenestration area shall have a maximum SHGC value of 0.23 in Climate Zone 15.

    Exception 2 to Section 150.2(b)1A: Alterations that add up to 16 square feet of new fenestration or skylight area shall not be required to meet the total fenestration area and west-facing fenestration area requirements of Sections 150.1(c)3B and C. B. Replacement fenestration. New manufactured fenestration products installed to replace existing fenestration products of the same total area shall meet the U-factor and Solar Heat Gain Coefficient requirements of Sections 150.1(c)3A, and 150.1(c)4. Exception 1 to Section 150.2(b)1B: Replacement of vertical fenestration no greater than 75 square feet with a U factor no greater than 0.40 in Climate Zones 1–16, and a SHGC value no greater than 0.35 in Climate Zones 2, 4 and 6 through 15. Exception 2 to Section 150.2(b)1B: Replaced skylights must meet a U -factor no greater than 0.40, and a SHGC value no greater than 0.30. Exception 3 to Section 150.2(b)1B: Replacement of vertical fenestration shall have a maximum SHGC value not greater than 0.23 in Climate Zone 15. Note: Glass replaced in an existing sash and frame or sashes replaced in an existing frame are considered repairs, provided that the replacement is at least equivalent to the original in performance. C. Entirely new or complete replacement space-conditioning systems installed as part of an alteration, shall include all the system heating or cooling equipment, including but not limited to: condensing unit, cooling or heating coil, and air handler for split systems; or complete replacement of a packaged unit; plus entirely new or replacement duct system [Section 150.2(b)1Diia].

  • § 0.46 High relevance — show source text

    46| |Operable Window (Max_U_-factor)|0.46|0.46|0.46|0.46|0.46|0.46|0.46|0.46|0.46|0.46|0.46|0.46|0.46|0.46|0.46|0.46| |Operable Window (Max RSHGC)|0.22|0.22|0.22|0.22|0.22|0.22|0.22|0.22|0.22|0.22|0.22|0.22|0.22|0.22|0.22|0.22| |Operable Window (Min VT)|0.32|0.32|0.32|0.32|0.32|0.32|0.32|0.32|0.32|0.32|0.32|0.32|0.32|0.32|0.32|0.32| |Glazed Doors (Max_U_-factor)|0.45|0.45|0.45|0.45|0.45|0.45|0.45|0.45|0.45|0.45|0.45|0.45|0.45|0.45|0.45|0.45| |Glazed Doors (Max RSHGC)|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23| |Glazed Doors (Min VT)|0.17|0.17|0.17|0.17|0.17|0.17|0.17|0.17|0.17|0.17|0.17|0.17|0.17|0.17|0.17|0.17| |Fenestration (Max WWR %)|40%|40%|40%|40%|40%|40%|40%|40%|40%|40%|40%|40%|40%|40%|40%|40%|

    FENESTRATION – SKYLIGHTS (all climate zones)
    (area-weighted performance rating)
    GLASS
    CURB MOUNTED
    GLASS
    DECK MOUNTED
    PLASTIC
    CURB MOUNTED
    TUBULAR DAYLIGHTING
    DEVICES (TDDS)
    Max U-factor 0.58 0.46 0.88 0.88
    Max SHGC 0.25 0.25 NR NR
    Min VT (Min VTannual for TDDs) 0.49 0.49 0.64 0.38
    Maximum SRR % 5% 5% 5% 5%
    Note:
    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 capac-
    ity of at least 15.0 Btu/ft2-°F.
    Note:
    1.
  • § 170.2 High relevance — show source text
    1. 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. Exception 2 to Section 170.2(a)3Aii: For fenestration containing chromogenic type glazing:

    a. 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; b. Chromogenic glazing shall be considered separately from other fenestration; and c. 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 3 to Section 170.2(a)3Aii: 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 Nonresidential Reference Appendix NA6 or using default values in Table 110.6-A and Table 110.6-B. Exception 4 to Section 170.2(a)3Aii: Fenestration in dwelling units of buildings in Climate Zones 1, 3, 5 and 16 is not required to comply with the RSHGC requirements. Exception 5 to Section 170.2(a)3Aii: Fenestration in dwelling units is not required to comply with the VT requirements. iii. Shading. Where Table 170.2-A requires a maximum RSHGC, the requirements shall be met with an area-weighted average RSHGC excluding the effects of interior shading, no greater than the applicable value in Table 170.2-A.

  • § 180.2 High relevance — show source text

    i. Fenestration installed to replace existing fenestration of the same total area shall meet either a or b: a. The maximum U- factor, RSHGC and VT requirements of Table 180.2-B, or b. The area-weighted U- factor and RSHGC of Table 170.2-A. Exception 1 to Section 180.2(b)1Ci: In an alteration, where 150 square feet or less of the entire building's vertical fenestration is replaced, RSHGC and VT requirements of Table 180.2-B shall not apply. ii. Alterations that add vertical fenestration and skylight area shall meet the total fenestration area requirements of Section 170.2(a)3 and the RSHGC and VT requirements of Table 180.2-B. Exception 1 to Section 180.2(b)1Cii: Alterations that add vertical fenestration area of up to 50 square feet shall not be required to meet the total fenestration area requirements of Sections 170.2(a)3, nor the RSHGC and VT requirements of Table 180.2-B. Exception 2 to Section 180.2(b)1Cii: Alterations that add up to 16 square feet of new skylight area per dwelling unit with a maximum U- factor of 0.55 and a maximum RSHGC of 0.30 shall not be required to meet the total fenestration area requirements of Section 170.2(a)3. D. Exterior doors. Alterations that add exterior door area shall meet the U- factor requirement of Section 170.2(a)4.

    TABLE 180.2-B—ALTERED FENESTRATION MAXIMUM U-FACTOR AND MAXIMUM SHGC AND RSHGC, MINIMUM VT Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10 Col11 Col12 Col13 Col14 Col15 Col16 Col17 Col18
    BUILDING TYPE FEATURE CZ 1 CZ 2 CZ 3 CZ 4 CZ 5 CZ 6 CZ 7 CZ 8 CZ 9 CZ 10 CZ 11 CZ 12 CZ 13 CZ 14 CZ 15 CZ 16
    Curtainwall/Storefront/
    Window Wall1
    U-factor 0.38 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.38
    Curtainwall/Storefront/
    Window Wall1
    RSHGC NR 0.26 NR 0.26 NR 0.26 0.26 0.26 0.26 0.26 0.26 0.26 0.26 0.26 0.26 NR
    Curtainwall/Storefront/
    Window Wall1
    VT2 0.46 0.46 0.
  • § 150.1 High relevance — show source text

    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. B. The maximum total fenestration area shall not exceed the percentage of conditioned floor area CFA as indicated in Table 150.1-A. Total fenestration includes skylights and west-facing glazing. C. The maximum west-facing fenestration area shall not exceed the percentage of conditioned floor area as indicated in Table 150.1-A. West-facing fenestration area includes skylights tilted in any direction when the pitch is less than 1:12. 4. Shading. Where Table 150.1-A requires a maximum SHGC, the shading requirements shall be met by one of the following: A. Complying with the required maximum SHGC pursuant to Section 150.1(c)3A, or B. An exterior operable shading louver or other exterior shading device that meets the required maximum SHGC; or C. A combination of Items A and B to achieve the same performance as achieved in Section 150.1(c)3A. D. For south-facing glazing only, optimal overhangs shall be installed so that the south-facing glazing is fully shaded at solar noon on August 21 and substantially exposed to direct sunlight at solar noon on December 21. E. Exterior shading devices must be permanently secured with attachments or fasteners that are not intended for removal.

    Exception to Section 150.1(c)4E: Where the California Building Code (CBC) requires emergency egress or where compliance would conflict with health and safety regulations. 5. Doors. Installed swinging door products separating conditioned space from outside or adjacent unconditioned space, but not including glazed door products, shall have an area-weighted average U-factor no greater than the applicable door value in Table 150.1-A and shall be determined in accordance with Section 110.6(a)2.

  • § 0.037 High relevance — show source text

    037
    R-19|U-0.037
    R-19|U-0.037
    R-19|U-0.037
    R-19|U-0.037
    R-19|U-0.037
    R-19|U-0.037
    R-19|U-0.037
    R-19| |Concrete Raised Floors|U-0.092
    R-8.0|U-0.092
    R-8.0|U-0.269
    R-0|U-0.269
    R-0|U-0.269
    R-0|U-0.269
    R-0|U-0.269
    R-0|U-0.269
    R-0|U-0.269
    R-0|U-0.269
    R-0|U-0.092
    R-8.0|U-0.138
    R-4.0|U-0.092
    R-8.0|U-0.092
    R-8.0|U-0.138
    R-4.0|U-0.092
    R-8.0| |Fenestration - Maximum
    U-factor12|0.27|0.27|0.27|0.27|0.27|0.30|0.30|0.30|0.30|0.30|0.27|0.27|0.27|0.27|0.30|0.27| |Fenestration - Maximum
    SHGC|NR|0.23|NR|0.23|NR|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.23|0.203|NR| |Fenestration - Maximum
    Total Area|20%|20%|20%|20%|20%|20%|20%|20%|20%|20%|20%|20%|20%|20%|20%|20%| |Fenestration - Maximum
    West Facing Area|NR|5%|NR|5%|NR|5%|5%|5%|5%|5%|5%|5%|5%|5%|5%|NR| |Door - Maximum_U_-Factor|0.20|0.20|0.20|0.20|0.20|0.20|0.20|0.20|0.20|0.20|0.20|0.20|0.20|0.20|0.20|0.20| |Quality Insulation
    Installation|Yes|Yes|Yes|Yes|Yes|Yes|Yes|Yes|Yes|Yes|Yes|Yes|Yes|Yes|Yes|Yes| |Space Heating - Electric
    Resistance Allowed|No|No|No|No|No|No|No|No|No|No|No|No|No|No|No|No| |Space Heating - If gas,
    AFUE10|NA|NA|NA|NA|NA|NA|NA|NA|NA|NA|NA|NA|NA|NA|NA|NA|

    2025 CALIFORNIA ENERGY CODE 183

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

    SINGLE-FAMILY RESIDENTIAL BUILDINGS—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES

    |TABLE 150.

  • § 170.2 High relevance — show source text

    Exception 2 to Section 170.2(a)3Aii: For fenestration containing chromogenic type glazing:

    a. 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; b. Chromogenic glazing shall be considered separately from other fenestration; and c. 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 3 to Section 170.2(a)3Aii: 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 Nonresidential Reference Appendix NA6 or using default values in Table 110.6-A and Table 110.6-B. Exception 4 to Section 170.2(a)3Aii: Fenestration in dwelling units of buildings in Climate Zones 1, 3, 5 and 16 is not required to comply with the RSHGC requirements. Exception 5 to Section 170.2(a)3Aii: Fenestration in dwelling units is not required to comply with the VT requirements. iii. Shading. Where Table 170.2-A requires a maximum RSHGC, the requirements shall be met with an area-weighted average RSHGC excluding the effects of interior shading, no greater than the applicable value in Table 170.2-A. For the purposes of this paragraph, the RSHGC of a vertical window is: a. The solar heat gain coefficient of the window; or b. Relative solar heat gain coefficient is calculated using Equation 170.2-A, if the window has an overhang that extends beyond each side of the window jamb by a distance equal to the overhang’s horizontal projection. Exception 1 to Section 170.2(a)3Aiiib: An area-weighted average relative solar heat gain coefficient of 0.56 or less shall be used for windows:

    I. That are in the first story of exterior walls that form a display perimeter; and II. For which codes restrict the use of overhangs to shade the windows. Exception 2 to Section 170.2(a)3Aiiib: For vertical glazing containing chromogenic type glazing:

    I. the lower-rate labeled RSHGC shall be used with automatic controls to modulate the amount of heat flow into the space in multiple steps in response to daylight levels or solar intensity; and II. chromogenic glazing shall be considered separately from other glazing; and III. area-weighted averaging with other glazing that is not chromogenic shall not be permitted.

    NOTE: Demising walls are not exterior walls, and therefore fenestration in demising walls is not subject to SHGC requirements. (Equation 170.2-A) RSHGC = SHGC × [1 + a × (2.72 [-PF] – 1) × (sin(b × Az) + c)]

    where:

    COMPONENT a b c
    Overhang 0.150 0.008727 5.67
    Exterior Horizontal Slat 0.144 0.008727 5.13

    RSHGC = Relative solar heat gain coefficient.

    SHGC = Solar heat gain coefficient of the vertical fenestration.

    Az = Azimuth of the vertical fenestration in degrees.

  • § 4.420 High relevance — show source text

    410|≥4.420|NA|AHRI
    550/590| |Water
    source
    electri-
    cally
    operated
    positive
    displace-
    ment|<75|≤0.7885
    FL
    ≤0.6316
    IPLV.IP|≤0.7875
    FL
    ≤0.5145
    IPLV.IP|75/655|NA|NA|NA|≥3.550|NA|NA|NA|6.150|6.150| |Water
    source
    electri-
    cally
    operated
    positive
    displace-
    ment|≥75
    and
    <150|≤0.7579
    FL
    ≤0.5895
    IPLV.IP|≤0.7140
    FL
    ≤0.4620
    IPLV.IP|54/445|≥4.640|≥3.680|≥2.680|NA|≥8.330|≥6.410|≥4.420|NA|NA| |Water
    source
    electri-
    cally
    operated
    positive
    displace-
    ment|≥75
    and
    <150|≤0.7579
    FL
    ≤0.5895
    IPLV.IP|≤0.7140
    FL
    ≤0.4620
    IPLV.IP|75/655|NA|NA|NA|≥3.550|NA|NA|NA|6.150|6.150| |Water
    source
    electri-
    cally
    operated
    positive
    displace-
    ment|≥150
    and
    <300|≤0.6947
    FL
    ≤0.5684
    IPLV.IP|≤0.7140
    FL
    ≤0.4620
    IPLV.IP|54/445|≥4.640|≥3.680|≥2.680|NA|≥8.330|≥6.410|≥4.420|NA|NA| |Water
    source
    electri-
    cally
    operated
    positive
    displace-
    ment|≥150
    and
    <300|≤0.6947
    FL
    ≤0.5684
    IPLV.IP|≤0.7140
    FL
    ≤0.4620
    IPLV.IP|75/655|NA|NA|NA|≥3.550|NA|NA|NA|6.150|6.150| |Water
    source
    electri-
    cally
    operated
    positive
    displace-
    ment|≥300
    and
    <600|≤0.6421
    FL
    ≤0.5474
    IPLV.IP|≤0.6563
    FL
    ≤0.4305
    IPLV.IP|54/445|≥4.930|≥3.960|≥2.970|NA|≥8.900|≥6.

  • § 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

    1. 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.

    2. 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.

  • California Energy Code High relevance — show source text

    (inch)|TYPE B DOUBLE-WALL VENT AND CONNECTOR DIAMETER –****D (inch)|TYPE B DOUBLE-WALL VENT AND CONNECTOR DIAMETER –****D (inch)|TYPE B DOUBLE-WALL VENT AND CONNECTOR DIAMETER –****D (inch)|TYPE B DOUBLE-WALL VENT AND CONNECTOR DIAMETER –****D (inch)|TYPE B DOUBLE-WALL VENT AND CONNECTOR DIAMETER –****D (inch)|TYPE B DOUBLE-WALL VENT AND CONNECTOR DIAMETER –****D (inch)| |||8|8|8|9|9|9|10|10|10| |||APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR| |VENT
    HEIGHT
    _H _
    (feet)|CONNECTOR
    RISE
    _R _
    (feet)|FAN|FAN|NAT|FAN|FAN|NAT|FAN|FAN|NAT| |VENT
    HEIGHT
    _H _
    (feet)|CONNECTOR
    RISE
    _R _
    (feet)**|Min|Max|Max|Min|Max|Max|Min|Max|Max| |6|1
    2
    3|92
    95
    97|296
    333
    363|185
    220
    248|109
    112
    114|376
    424
    463|237
    282
    317|128
    131
    134|466
    526
    575|289
    345
    386| |8|1
    2
    3|100
    103
    105|320
    356
    384|194
    230
    258|118
    121
    123|408
    454
    492|248
    294
    330|138
    141
    143|507
    564
    612|303
    358
    402| |10|1
    2

  • § 0.36 High relevance — show source text
    FENESTRATION – VERTICAL (all climate zones)
    (area-weighted performance rating)
    FIXED
    WINDOW
    OPERABLE
    WINDOW
    CURTAIN WALL
    AND
    STOREFRONT
    GLAZED DOORS2
    Max U-factor 0.36 0.46 0.41 0.45
    Max RSHGC 0.25 0.22 0.26 0.23
    Min VT 0.42 0.32 0.46 0.17
    Maximum WWR % 40% 40% 40% 40%
    FENESTRATION – SKYLIGHTS (all climate zones)
    (area-weighted performance rating)
    GLASS
    CURB MOUNTED
    GLASS
    DECK MOUNTED
    PLASTIC
    CURB MOUNTED
    Max U-factor 0.58 0.46 0.88
    Max SHGC 0.25 0.25 NR
    Min VT 0.49 0.49 0.64
    Maximum SRR % 5% 5% 5%
    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.
    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.

  • California Energy Code High relevance — show source text

    DOUBLE-WALL VENT CONNECTOR DIAMETER –D (inch)|TYPE B DOUBLE-WALL VENT CONNECTOR DIAMETER –****D (inch)|TYPE B DOUBLE-WALL VENT CONNECTOR DIAMETER –D (inch)|TYPE B DOUBLE-WALL VENT CONNECTOR DIAMETER –****D (inch)|TYPE B DOUBLE-WALL VENT CONNECTOR DIAMETER –****D (inch)|TYPE B DOUBLE-WALL VENT CONNECTOR DIAMETER –****D (inch)|TYPE B DOUBLE-WALL VENT CONNECTOR DIAMETER –****D (inch)|TYPE B DOUBLE-WALL VENT CONNECTOR DIAMETER –****D (inch)| |||8|8|8|9|9|9|10|10|10| |||APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR|APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU PER HOUR| |VENT
    HEIGHT
    _H _
    (feet)|CONNECTOR
    RISE
    _R _
    (feet)|FAN|FAN|NAT|FAN|FAN|NAT|FAN|FAN|NAT| |VENT
    HEIGHT
    _H _
    (feet)|CONNECTOR
    RISE
    _R _
    (feet)**|Min|Max|Max|Min|Max|Max|Min|Max|Max| |6|1
    2
    3|104
    107
    109|370
    436
    491|201
    232
    270|124
    127
    129|479
    562
    633|253
    300
    349|145
    148
    151|599
    694
    795|319
    378
    439| |8|1
    2
    3|113
    116
    119|414
    473
    517|210
    240
    276|134
    137
    139|539
    615
    672|267
    311
    358|156
    160
    163|682
    776
    848|335
    394
    452| |10|1
    2

  • § 62.1 Medium relevance — show source text

    [ASHRAE 62.1:Table 5.16.1] Table 120.1-C, Table 160.2-D Airtightness 150.0(k)1C, 160.5(a)1C Aisle Way 130.1(c)6 Allotment 140.6(b)3, 140.6(c), 170.2(e)3-4 Alterations 10-103(a), 10-103(d)2, 10-106(a), 100.0(e), 100.0-A, Table 120.2-A, 120.6(c), 120.6(e), 130.0(a), 130.0(b), 140.0(c), 141.0, 141.0(b), 141.0(d), 141.1(b-c), 150.0, 150.1(a), 150.1(b)2, 150.2(b), 160.0, Table 160.3-C, 160.5(b), 170.0(a), 180.0, 180.2, 180.2(b) Altered 141.0(b)2C Altered Components 141.0(a)2, 150.2(a)2B, 150.2(b)2A, 180.1(b)2, 180.2(a), 180.2(c) Altered Duct System 141.0(b)2D, 150.2(b)1D, 160.3(d)1, 180.2(b)2A Altered Fenestration Maximum U-Factor and

    Maximum RSHGC Table 180.2-B Altered Luminaire 141.0(b)2I, 141.0(b)L, 150.2(b)1K, 180.2(b)4 Altered Ventilation System 150.2(b)1M, 180.2(b)5B Altered Vertical Fenestration

    Maximum U-Factor and

    Maximum RSHGC Table 141.0-A Alternate Lighting Sources 140.8(b), 170.2(e)7B Alternating Current-Output Uninterruptible Power Supplies (UPS) 140.9(a)4 Alternating Current-Output Uninterruptible Power Supply Minimum Average Efficiency Table 140.9-B Alternative Calculation Method (ACM) Approval Manual 150.1(b) Alternative Plumbing 110.10(b)1A , 110.10(b)1B Alternative Procedure 10-109(h), 150.1(c)7 , 150.2(b)1F, 170.2(c)3B, 180.2(b)2A Aluminum-pigmented 110.8(i)4B Ambient Air 120.7(a-c) , 140.3(a)7 , 141.0(b)1 , 141.0(b)1C, 150.0(a), 150.0(c), 150.0(d), 160.1(a), 160.1(b), 160.1(c), 170.2(a)4, 170.2(d)2F, 180.2(a) American National Standards Institute (ANSI) 150.0(m)1 , 150.0(p) ANSI/AHRI 110.

  • California Energy Code Medium relevance — show source text

    10|—|3|30|8|4@25|4@48|4@48|4@48|4@18|4@22|4@18| |130|110|—|3|30|10|4@19|5@36|4@48|4@48|4@14|4@17|4@13| |130|110|—|6|60|10|4@16|5@34|4@48|4@48|4@12|4@17|4@12| |130|110|—|6|30|10|DR|5@19|6@35|4@48|DR|4@9|DR| |130|110|—|6|60|10|DR|5@12|6@24|6@28|DR|DR|DR| |140|119|110|3|30|8|4@22|5@42|4@48|4@48|4@16|4@20|4@16| |140|119|110|3|30|10|4@17|5@34|4@48|4@48|4@21|4@17|4@12| |140|119|110|3|60|10|4@15|5@34|4@48|4@48|4@11|4@17|4@10| |140|119|110|6|30|10|DR|5@18|6@35|6@35|DR|4@48|DR| |140|119|110|6|60|10|DR|5@11|6@23|6@28|DR|DR|DR| |150|127|117|3|30|8|4@20|5@37|4@48|4@48|4@15|4@18|4@14| |150|127|117|3|30|10|4@15|5@34|4@48|4@48|4@11|4@17|4@11| |150|127|117|3|60|10|4@13|5@34|4@48|4@48|4@10|4@16|4@9| |150|127|117|6|30|10|DR|5@17|6@33|6@32|DR|4@8|DR| |150|127|117|6|60|10|DR|DR|6@22|6@28|DR|DR|DR| |160|136|12

  • § 0.59 Medium relevance — show source text

    12|NA| |Metal, thermal break|Glazed doors|NA|0.59|NA| |Metal, thermal break|Skylight|NA|1.11|NA| |Nonmetal|Operable|0.99|0.58|0.60| |Nonmetal|Fixed|1.04|0.55|0.57| |Nonmetal|Greenhouse/garden window|0.99|0.53|NA| |Nonmetal|Glazed doors|1.94|1.06|NA| |Nonmetal|Skylight|1.47|0.84|NA| |1. For all dual-glazed fenestration products, adjust the listed_U_-factors as follows:
    a. Add 0.05 for products with dividers between panes if spacer is less than7/16 inch wide.
    b. Add 0.05 to any product with true divided lite (dividers through the panes).
    2. Translucent or transparent panels shall use glass block values when not rated by NFRC 100.
    3. Visible Transmittance (VT) shall be calculated by using Reference Nonresidential Appendix NA6.
    4. Windows with window film applied that is not rated by NFRC 100 shall use the default values from this table.|1. For all dual-glazed fenestration products, adjust the listed_U_-factors as follows:
    a. Add 0.05 for products with dividers between panes if spacer is less than7/16 inch wide.
    b. Add 0.05 to any product with true divided lite (dividers through the panes).
    2. Translucent or transparent panels shall use glass block values when not rated by NFRC 100.
    3. Visible Transmittance (VT) shall be calculated by using Reference Nonresidential Appendix NA6.
    4. Windows with window film applied that is not rated by NFRC 100 shall use the default values from this table.|1. For all dual-glazed fenestration products, adjust the listed_U_-factors as follows:
    a. Add 0.05 for products with dividers between panes if spacer is less than7/16 inch wide.
    b. Add 0.05 to any product with true divided lite (dividers through the panes).
    2. Translucent or transparent panels shall use glass block values when not rated by NFRC 100.
    3. Visible Transmittance (VT) shall be calculated by using Reference Nonresidential Appendix NA6.
    4. Windows with window film applied that is not rated by NFRC 100 shall use the default values from this table.|1. For all dual-glazed fenestration products, adjust the listed_U_-factors as follows:
    a. Add 0.05 for products with dividers between panes if spacer is less than7/16 inch wide.
    b. Add 0.05 to any product with true divided lite (dividers through the panes).
    2. Translucent or transparent panels shall use glass block values when not rated by NFRC 100.
    3. Visible Transmittance (VT) shall be calculated by using Reference Nonresidential Appendix NA6.
    4. Windows with window film applied that is not rated by NFRC 100 shall use the default values from this table.|1. For all dual-glazed fenestration products, adjust the listed_U_-factors as follows:
    a.

  • § 0.05 Medium relevance — show source text

    Visible Transmittance (VT) shall be calculated by using Reference Nonresidential Appendix NA6.
    4. Windows with window film applied that is not rated by NFRC 100 shall use the default values from this table.|1. For all dual-glazed fenestration products, adjust the listed_U_-factors as follows:
    a. Add 0.05 for products with dividers between panes if spacer is less than7/16 inch wide.
    b. Add 0.05 to any product with true divided lite (dividers through the panes).
    2. Translucent or transparent panels shall use glass block values when not rated by NFRC 100.
    3. Visible Transmittance (VT) shall be calculated by using Reference Nonresidential Appendix NA6.
    4. Windows with window film applied that is not rated by NFRC 100 shall use the default values from this table.|1. For all dual-glazed fenestration products, adjust the listed_U_-factors as follows:
    a. Add 0.05 for products with dividers between panes if spacer is less than7/16 inch wide.
    b. Add 0.05 to any product with true divided lite (dividers through the panes).
    2. Translucent or transparent panels shall use glass block values when not rated by NFRC 100.
    3. Visible Transmittance (VT) shall be calculated by using Reference Nonresidential Appendix NA6.
    4. Windows with window film applied that is not rated by NFRC 100 shall use the default values from this table.|1. For all dual-glazed fenestration products, adjust the listed_U_-factors as follows:
    a. Add 0.05 for products with dividers between panes if spacer is less than7/16 inch wide.
    b. Add 0.05 to any product with true divided lite (dividers through the panes).
    2. Translucent or transparent panels shall use glass block values when not rated by NFRC 100.
    3. Visible Transmittance (VT) shall be calculated by using Reference Nonresidential Appendix NA6.
    4. Windows with window film applied that is not rated by NFRC 100 shall use the default values from this table.|

    TABLE 110.6-B—DEFAULT SOLAR HEAT GAIN COEFFICIENT (SHGC) Col2 Col3 Col4 Col5 Col6
    FRAME TYPE PRODUCT GLAZING FENESTRATION PRODUCT SHGC FENESTRATION PRODUCT SHGC FENESTRATION PRODUCT SHGC
    FRAME TYPE PRODUCT GLAZING Single Pane2, 3
    SHGC
    Double Pane2, 3
    SHGC
    Glass Block1, 2
    SHGC
    Metal Operable Clear 0.80 0.70 0.70
    Metal Fixed Clear 0.83 0.73 0.73
    Metal Operable Tinted 0.67 0.59 NA
    Metal Fixed Tinted 0.68 0.60 NA
    Metal, thermal break Operable Clear NA 0.63 NA
    Metal, thermal break Fixed Clear NA 0.69 NA
    Metal, thermal break Operable Tinted NA 0.
  • § 15.0 Medium relevance — show source text

    Heavy mass walls are walls with a heat capac-
    ity of at least 15.0 Btu/ft2-°F.|Note:
    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 capac-
    ity of at least 15.0 Btu/ft2-°F.|Note:
    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 capac-
    ity of at least 15.0 Btu/ft2-°F.|Note:
    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 capac-
    ity of at least 15.0 Btu/ft2-°F.|

    110 2025 CALIFORNIA ENERGY CODE

    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-C —PRESCRIPTIVE ENVELOPE CRITERIA FOR GUEST ROOMS OF HOTEL/MOTEL BUILDINGS Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10 Col11 Col12 Col13 Col14 Col15 Col16 Col17
    ENVELOPE FEATURE CZ 1 CZ 2 CZ 3 CZ 4 CZ 5 CZ 6 CZ 7 CZ 8 CZ 9 CZ 10 CZ 11 CZ 12 CZ 13 CZ 14 CZ 15 CZ 16
    Roofs and Ceilings – Metal
    Building Max U-Factor
    0.041 0.041 0.041 0.041 0.041 0.041 0.041 0.041 0.041 0.041 0.041 0.041 0.041 0.041 0.041 0.041
    Roofs and Ceilings – Wood-
    Framed and Other
    Max U-Factor
    0.028 0.028 0.034 0.028 0.034 0.034 0.039 0.028 0.028 0.028 0.028 0.028 0.028 0.028 0.028 0.028
    Walls – Metal Building
    Max U-Factor
    0.061 0.061 0.
  • § 25.4 Medium relevance — show source text

    B**|** C**|** D**|** D**|** Topi**|** Sidei**| |115|—|—|8|4@48|4@48| |115|—|—|9|4@48|5@41| |115|—|—|10|4@48|6@48| |120|—|—|8|4@48|4@48| |120|—|—|9|4@48|5@38| |120|—|—|10|5@42|6@48| |130|110|—|8|4@48|5@41| |130|110|—|9|5@44|6@48| |130|110|—|10|5@35|6@48| |140|119|110|8|4@48|5@36| |140|119|110|9|5@38|6@48| |140|119|110|10|6@48|6@48| |150|127|117|8|5@42|6@48| |150|127|117|9|6@48|6@48| |150|127|117|10|6@48|6@42| |160|136|125|8|5@37|6@48| |160|136|125|9|6@48|6@45| |160|136|125|10|6@44|6@38| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 mile per hour = 0.447 m/s, 1 pound per square inch = 6.895 kPa, 1 square foot = 0.0929 m2.
    a. Table is based on ASCE 7 components and cladding wind pressures for an enclosed building using a mean roof height of 35 feet, interior wall area 4, an effective wind area of
    10 square feet, topographic factor,Kzt, equal to 1.0, and Risk Category II.
    b. Table is based on concrete with a minimum specified compressive strength of 2,500 psi.
    c. See Section R608.6.5 for location of reinforcement in wall.
    d. Deflection criterion is_L_/240, where_L_ is the unsupported height of the wall in inches.
    e. Interpolation is not permitted.
    f. Where No. 4 reinforcing bars at a spacing of 48 inches are specified in the table as indicated by shaded cells, use of bars with a minimum yield strength of 40,000 psi or 60,000
    psi is permitted.
    g. Other than for No. 4 bars spaced at 48 inches on center, table values are based on reinforcing bars with a minimum yield strength of 60,000 psi. Maximum spacings shown are
    the values calculated for the specified bar size. Where the bar used is Grade 60 and the size specified in the table, the actual spacing in the wall shall not exceed a whole-
    number multiple of 12 inches such as, 12, 24, 36 and 48, that is less than or equal to the tabulated spacing. Vertical reinforcement with a yield strength of less than 60,000 psi
    or bars of a different size than specified in the table are permitted in accordance with Section R608.5.4.7 and Table R608.5.4(2).
    h. See Table R608.3 for minimum core dimensions and maximum spacing of horizontal and vertical cores.
    i.

  • § 5.5 Medium relevance — show source text

    5|5.5|4.5| |≤ 110||20|NP|17.0|10.0|8.5| |≤ 110||30|NP|24.5|14.0|12.0| |≤ 110||40|NP|32.0|18.5|15.5| |≤ 110||50|NP|39.5|22.5|19.0| |≤ 110||60|NP|46.5|26.5|23.0|

    2025 CALIFORNIA RESIDENTIAL CODE 6-27

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

    WALL CONSTRUCTION

    TABLE R602.10.3(1)—BRACING REQUIREMENTS BASED ON WIND SPEED—continued Col2 Col3 Col4 Col5 Col6 Col7

    EXPOSURE CATEGORY B

    30-FOOT MEAN ROOF HEIGHT

    10-FOOT WALL HEIGHT

    2 BRACED WALL LINES

    EXPOSURE CATEGORY B

    30-FOOT MEAN ROOF HEIGHT

    10-FOOT WALL HEIGHT

    2 BRACED WALL LINES

    EXPOSURE CATEGORY B

    30-FOOT MEAN ROOF HEIGHT

    10-FOOT WALL HEIGHT

    2 BRACED WALL LINES
    MINIMUM TOTAL LENGTH (FEET) OF BRACED
    WALL PANELS REQUIRED ALONG EACH BRACED WALL LINEa
    MINIMUM TOTAL LENGTH (FEET) OF BRACED
    WALL PANELS REQUIRED ALONG EACH BRACED WALL LINEa
    MINIMUM TOTAL LENGTH (FEET) OF BRACED
    WALL PANELS REQUIRED ALONG EACH BRACED WALL LINEa
    MINIMUM TOTAL LENGTH (FEET) OF BRACED
    WALL PANELS REQUIRED ALONG EACH BRACED WALL LINEa
    Ultimate Design
    Wind Speed
    (mph)
    Story Location Braced Wall
    Line Spacingc
    (feet)
    Method
    LIBb
    Method
    GB
    Methods
    DWB, WSP, SFB, PBS,
    PCP, HPS, BV-WSP, ABW,
    PFH, PFG, CS-SFB
    Methods
    CS-WSP, CS-G, CS-PF
    ≤ 115 10 3.5 3.5 2.0 2.0
    ≤ 115 20 6.5 6.5 3.5 3.5
    ≤ 115 30 9.5 9.5 5.5 4.5
    ≤ 115 40 12.5 12.5 7.
  • § 6-120 Medium relevance — show source text

    6-120 2025 CALIFORNIA RESIDENTIAL CODE

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

    WALL CONSTRUCTION

    TABLE R608.6(3)—MINIMUM VERTICAL REINFORCEMENT FOR 6-INCH SCREEN-GRID ABOVE-GRADE WALLSa, b, c, d, e Col2 Col3 Col4 Col5 Col6
    ** MAXIMUM WIND SPEED**
    (mph)
    ** MAXIMUM WIND SPEED**
    (mph)
    ** MAXIMUM WIND SPEED**
    (mph)
    ** MAXIMUM**
    UNSUPPORTED WALL HEIGHT PER STORY
    (feet)
    ** MINIMUM VERTICAL REINFORCEMENT-BAR SIZE AND SPACING**
    (inches)f, g
    ** MINIMUM VERTICAL REINFORCEMENT-BAR SIZE AND SPACING**
    (inches)f, g
    ** MAXIMUM WIND SPEED**
    (mph)
    ** MAXIMUM WIND SPEED**
    (mph)
    ** MAXIMUM WIND SPEED**
    (mph)
    ** MAXIMUM**
    UNSUPPORTED WALL HEIGHT PER STORY
    (feet)
    ** Nominalh wall thickness**
    (inches)
    ** Nominalh wall thickness**
    (inches)
    ** Exposure category** ** Exposure category** ** Exposure category** ** Exposure category** ** 6** ** 6**
    ** B** ** C** ** D** ** D** ** Topi** ** Sidei**
    115 8 4@48 4@48
    115 9 4@48 5@41
    115 10 4@48 6@48
    120 8 4@48 4@48
    120 9 4@48 5@38
    120 10 5@42 6@48
    130 110 8 4@48 5@41
    130 110 9 5@44 6@48
    130 110 10 5@35 6@48
    140 119 110 8 4@48 5@36
    140 119 110 9 5@38 6@48
    140 119 110 10 6@48 6@48
    150 127 117 8 5@42 6@48
    150 127 117 9 6@48 6@48
    150 127 117 10 6@48 6@42
    160 136 125 8 5@37 6@48
    160 136 125 9 6@48 6@45
    160 136 125 10 6@44 6@38
    For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 mile per hour = 0.447 m/s, 1 pound per square inch = 6.895 kPa, 1 square foot = 0.0929 m2.
    a.
  • § 03-25 Medium relevance — show source text

    1 For application guide, see Note 23 on Page 3.

    062000 Page 20 of 26 Rev. #25: 03-25-22

    UG-1: Enclosures Greenbook Primary Electric Underground Enclosures

    4’ 6” x 8’ 6”(#7) Steel Quick-Release Cover Assembly− Full Traffic

    Col1 Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10
    110-13/16”


    110-13/16”


    110-13/16”


    110-13/16”


    110-13/16”


    110-13/16”


    110-13/16”


    110-13/16”


    34-1/8” 34-1/8” 38-5/16” 38-5/16” 38-5/16” 38-5/16” 34-1/8” 34-1/8”
    - 7/8”
    - 7/8”

    4-5/8”

    8-5/8”

    Plan Equipment Frame and Cover Assembly

    Side View

    Col1 Col2 Col3 Col4 Col5 Col6 Col7 Col8
    110-13/16”
    34-1/8”
    34-1/8”
    38-5/16”
    110-13/16”
    34-1/8”
    34-1/8”
    38-5/16”
    110-13/16”
    34-1/8”
    34-1/8”
    38-5/16”
    110-13/16”
    34-1/8”
    34-1/8”
    38-5/16”
    110-13/16”
    34-1/8”
    34-1/8”
    38-5/16”
    110-13/16”
    34-1/8”
    34-1/8”
    38-5/16”
    110-13/16”
    34-1/8”
    34-1/8”
    38-5/16”
    110-13/16”
    34-1/8”
    34-1/8”
    38-5/16”
    38-5/16” 38-5/16” 38-5/16” 34-1/8”
    - 7/8”
    - 7/8”

    Plan Transformer Frame and Cover Assembly

    Isometric View

    Figure 16 4’ 6” x 8’ 6” Steel Quick-Release Cover Assembly − Full Traffic

    Rev. #25: 03-25-22 062000 Page 21 of 26

  • § 18.5 Medium relevance — show source text

    5| |< 95 mph||30|NP|18.5|10.5|9.0| |< 95 mph||40|NP|24.0|13.5|11.5| |< 95 mph||50|NP|29.5|17.0|14.5| |< 95 mph||60|NP|35.0|20.0|17.0| |≤ 110||10|3.5|3.5|2.0|1.5| |≤ 110||20|6.0|6.0|3.5|3.0| |≤ 110||30|8.5|8.5|5.0|4.5| |≤ 110||40|11.5|11.5|6.5|5.5| |≤ 110||50|14.0|14.0|8.0|7.0| |≤ 110||60|16.5|16.5|9.5|8.0| |≤ 110||10|6.5|6.5|3.5|3.0| |≤ 110||20|11.5|11.5|6.5|5.5| |≤ 110||30|16.5|16.5|9.5|8.0| |≤ 110||40|21.5|21.5|12.5|10.5| |≤ 110||50|26.5|26.5|15.5|13.0| |≤ 110||60|31.5|31.5|18.0|15.5| |≤ 110||10|NP|9.5|5.5|4.5| |≤ 110||20|NP|17.0|10.0|8.5| |≤ 110||30|NP|24.5|14.0|12.0| |≤ 110||40|NP|32.0|18.5|15.5| |≤ 110||50|NP|39.5|22.5|19.0| |≤ 110||60|NP|46.5|26.5|23.0|

    2025 CALIFORNIA RESIDENTIAL CODE 6-27

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

    WALL CONSTRUCTION

    TABLE R602.10.3(1)—BRACING REQUIREMENTS BASED ON WIND SPEED—continued Col2 Col3 Col4 Col5 Col6 Col7

    EXPOSURE CATEGORY B

    30-FOOT MEAN ROOF HEIGHT

    10-FOOT WALL HEIGHT

    2 BRACED WALL LINES

    EXPOSURE CATEGORY B

    30-FOOT MEAN ROOF HEIGHT

    10-FOOT WALL HEIGHT

    2 BRACED WALL LINES

    EXPOSURE CATEGORY B

    **30-FOOT MEAN ROOF
  • § 0.25 Medium relevance — show source text

    e|(125)d, e|(125)d, e|125d|(125)d|(125)d|25d|(25)d| |Organic
    peroxide|IV|NA|NL|NL|NL|NL|NL|NL|NL|NL| |Organic
    peroxide|V|NA|NL|NL|NL|NL|NL|NL|NL|NL| |Oxidizer|4|H-1|1g|(1)e, g|NA|0.25g|(0.25)g|NA|0.25g|(0.25)g| |Oxidizer|3j|H-2 or H-3|10d, e|(10)d, e|(10)d, e|2d|(2)d|(2)d|2d|(2)d| |Oxidizer|2|H-3|250d, e|(250)d, e|(250)d, e|250d|(250)d|(250)d|50d|(50)d| |Oxidizer|1|NA|4,000e, f|(4,000)e, f|(4,000)e, f|4,000f|(4,000)f|(4,000)f|1,000f|(1,000)f| |Oxidizing gas|Gaseous|H-3|NA|NA|1,500d, e|NA|NA|1,500d, e|NA|NA| |Oxidizing gas|Liquefied|Liquefied|Liquefied|(150)d, e|NA|NA|(150)d, e|NA|NA|NA| |Pyrophoric|NA|H-2|4e, g|(4)e, g|50e, g|1g|(1)g|10e, g|0|0| |Unstable
    (reactive)|4|H-1|1e, g|(1)e, g|10e, g|0.25g|(0.25)g|2e, g|0.25g|(0.25)g| |Unstable
    (reactive)|3|H-1 or H-2|5d, e|(5)d, e|50d, e|1d|(1)d|10d, e|1d|(1)d| |Unstable
    (reactive)|2|H-3|50d, e|(50)d, e|750d, e|50d|(50)d|750d, e|10d|(10)d| |Unstable
    (reactive)|1|NA|NL|NL|NL|NL|NL|NL|NL|NL| |Water reactive|3|H-2|5d, e|(5)d, e|NA|5d|(5)d|NA|1d|(1)d| |Water reactive|2|H-3|50d, e|(50)d, e|(50)d, e|50d|(50)d|(50)d|10d|(10)d| |Water reactive|1|NA|NL|NL|NL|NL|NL|NL|NL|NL| |For SI: 1 cubic foot = 0.028 m3, 1 pound = 0.454 kg, 1 gallon = 3.785 L.
    NL = Not Limited; NA = Not Applicable; UD = Unclassified Detonable.
    a. For use of control areas, see Section 414.2.
    b. The aggregate quantity in use and storage shall not exceed the maximum allowable quantity for storage, including applicable increases.
    c._ Reserved._
    d.

  • § 15-11 Medium relevance — show source text

    COMPLIANCE FORMS, WORKSHEETS AND REFERENCE MATERIAL

    FOR REFERENCE ONLY: The following table has been reprinted from the IES TM-15-11 Reference standard, see Section 5.106.8.

    IES TM-15-11 TABLE A-1—BACKLIGHT RATINGS (Maximum Zonal Lumens) Col2 Col3 Col4 Col5 Col6
    SECONDARY SOLID ANGLE MAXIMUM ZONAL LUMENS PER OUTDOOR LIGHTING ZONE MAXIMUM ZONAL LUMENS PER OUTDOOR LIGHTING ZONE MAXIMUM ZONAL LUMENS PER OUTDOOR LIGHTING ZONE MAXIMUM ZONAL LUMENS PER OUTDOOR LIGHTING ZONE MAXIMUM ZONAL LUMENS PER OUTDOOR LIGHTING ZONE
    SECONDARY SOLID ANGLE LZ 0 LZ 1 LZ 2 LZ 3 LZ 4
    Backlight High (BH)
    60 to 80 degrees
    110 500 1,000 2,500 5,000
    Backlight Medium (BM)
    30 to < 60 degrees
    220 1,000 2,500 5,000 8,500
    Backlight Low (BL)
    0 to < 30 degrees
    110 500 1,000 2,500 5,000

    FOR REFERENCE ONLY: The following table has been reprinted from the California Energy Code, Part 6, Title 24, see Section 5.106.8.

    TABLE 130.2-A—UPLIGHT RATINGS (Maximum Zonal Lumens) Col2 Col3 Col4 Col5 Col6
    SECONDARY SOLID ANGLE MAXIMUM ZONAL LUMENS PER OUTDOOR LIGHTING ZONE MAXIMUM ZONAL LUMENS PER OUTDOOR LIGHTING ZONE MAXIMUM ZONAL LUMENS PER OUTDOOR LIGHTING ZONE MAXIMUM ZONAL LUMENS PER OUTDOOR LIGHTING ZONE MAXIMUM ZONAL LUMENS PER OUTDOOR LIGHTING ZONE
    SECONDARY SOLID ANGLE LZ 0 LZ 1 LZ 2 LZ 3 LZ 4
    Uplight High (UH)
    100 to 180 degrees
    0 10 50 500 1,000
    Uplight Low (UL)
    90 to < 100 degrees
    0 10 50 500 1,000

    FOR REFERENCE ONLY: The following table has been reprinted from the California Energy Code, Part 6, Title 24, see Section 5.106.8.

    TABLE 130.2-B—GLARE RATINGS (Maximum Zonal Lumens) Col2 Col3 Col4 Col5 Col6
    GLARE RATING FOR ASYMMETRICAL LUMINAIRE TYPES
    (Type I, Type II, Type III, Type IV)
    GLARE RATING FOR ASYMMETRICAL LUMINAIRE TYPES
    **(Type I, Type II, Type III,

Frequently asked questions

Can I mix labeled and unrated windows when calculating the area‑weighted U‑factor?

Yes — but unrated, site‑built products must use the methods in Nonresidential Reference Appendix NA6 or the default values in Table 110.6‑A/B; you cannot simply invent ratings. § 150.1(c)3(A) Exception 5 and § 170.2(a)3 Exception 3 explain this.

What is the difference between SHGC and RSHGC?

SHGC is the product’s rated solar heat gain coefficient. RSHGC is a relative SHGC that accounts for fixed exterior shading (the code provides Equation 170.2‑A to compute RSHGC for overhangs). Use RSHGC where the table or method requires it. § 170.2(a)3(iii).

Do skylights count toward the same area limits?

Yes — skylights are included in the total fenestration area and in some west‑facing area counts. However small skylight area exceptions (e.g., up to 16 ft²) and different skylight U/SHGC caps may apply (see § 150.1(c)3 exceptions).

How do I prove compliance for fenestration ratings?

Use labeled ratings or the calculation procedures specified in § 110.6. If you rely on default values for unrated products, use Table 110.6‑A/B or Appendix NA6 as allowed by the exceptions.

If I have overhangs, can I claim a lower RSHGC?

Yes — the code allows calculation of RSHGC using Equation 170.2‑A for fenestration with overhangs that project beyond the jambs; follow the equation and the parameters defined in § 170.2(a)3.

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