Title 24 · California Energy Code

Quality Insulation Installation (QII) requirements and where to find acceptance criteria

If the prescriptive tables or your chosen compliance path mark an assembly “QII required,” the California Energy Code (see **§ 150.1(c)E**) requires that insulation be installed and field‑verified per the acceptance criteria in **Reference Residential Appendix RA3.5**; consult RA3.5 itself for the exact test procedures and pass/fail thresholds. file

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

The California Energy Code requires that when the prescriptive tables or a chosen compliance path call for Quality Insulation Installation (QII), the installed insulation must meet the QII requirements shown in the applicable prescriptive table and be installed to the acceptance criteria in Reference Residential Appendix RA3.5. The controlling prescriptive statement is § 150.1(c)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.”

The single most important rule: if Table 150.1‑A (or the applicable prescriptive table) marks an element “QII required,” you must follow the field‑verification and installation acceptance procedures in Reference Appendix RA3.5.

Requirements in detail

Scope — which projects/elements must comply

  • All buildings/elements flagged as “QII required” in the prescriptive tables must meet QII. The prescriptive trigger is the entry in Table 150.1‑A (single‑family prescriptive) or the comparable multifamily table (e.g., Table 170.2‑A) that shows QII is required for a given envelope component and climate zone. § 150.1(c)E sets this general requirement.
  • When the performance compliance path relies on improved installed insulation (above the standard design) and that path requires field‑verification of QII, the insulation system must be field‑verified per Reference Appendix RA3.5.

What “QII required” means (process-level)

  • The prescriptive table entry tells the designer/installer whether QII is required for a given assembly or climate zone; compliance is accomplished by: (a) installing the insulation to the acceptance criteria in RA3.5, and (b) completing the associated field verification/documentation required by the code and reference appendices.
  • When compliance is by the performance path and QII field verification is required, the code cross‑references the same RA3.5 procedure for inspection and testing.

Decision‑relevant dimensions and where the code points you

Decision / question What the code requires / value Code Reference
Which assemblies require QII? Assemblies marked QII required in Table 150.1‑A (or Table 170.2‑A for multifamily) § 150.1(c)E; see Table 150.1‑A
If using performance compliance, when is QII verified? When the performance compliance approach depends on field‑verified QII, the building insulation system must be field‑verified per RA3.5 § 150.1(b) (field verification requirements) and § 150.1(c)E
Multifamily (up to 3 stories) QII trigger Multifamily prescriptive tables show QII; where QII is required, installations must meet RA3.5 § 170.2(a)6
Are additions always subject to QII? Small additions may be exempt — see exceptions for additions in the additions/alterations section Exception language in the additions/alterations sections (see § 150.2 and related notes) — example: small additions ≤ 700 ft²: QII of §150.1(c)1E does not apply to some small additions
Where are the QII acceptance criteria detailed? In Reference Residential Appendix RA3.5 (installation criteria, field‑verification procedures) § 150.1(c)E (direct cross‑reference to RA3.5)

(If you need the exact Table 150.1‑A entries for a particular climate zone or assembly, consult Table 150.1‑A in the code document. The code text explicitly ties the table entries to the QII requirement.)

What RA3.5 controls (summary — based on code cross‑reference)

  • The Code requires you to use RA3.5 for both the installation acceptance criteria and field verification procedures whenever QII is required by the prescriptive table or by the performance path. The Energy Code text repeatedly cross‑references RA3.5 for QII field verification for residential and small‑multifamily buildings. file

Note: the exact acceptance tests, sample rates, measurement procedures and pass/fail thresholds are contained in Reference Appendix RA3.5 itself. The copy of RA3.5 was not included among the uploaded files I searched, so I cannot quote or list RA3.5’s numeric thresholds here — you must consult the RA3.5 appendix in the full code or the residential appendices to get the step‑by‑step acceptance criteria.

Exceptions & special cases

  • Additions and alterations: Some smaller additions are explicitly exempt from the QII requirement for new construction; for example, additions 700 ft² or less have modified rules and in some places the QII requirement does not apply — check the additions/alterations subsection for the applicable exception in Section 150.2 (see the additions discussion referencing QII).
  • Multifamily buildings: The multifamily prescriptive section includes its own table (Table 170.2‑A) and QII triggers; multi‑family references to QII are handled in § 170.2(a)6 and also point to RA3.5 for acceptance criteria.
  • Performance path: When meeting the energy budget requires installed insulation performance better than the standard design, the performance path may require field verification of QII (per RA3.5) rather than the prescriptive table alone.

Common mistakes

  • Assuming “QII required” is optional. If Table 150.1‑A or the applicable prescriptive table flags QII, you must follow RA3.5. § 150.1(c)E makes this mandatory.
  • Looking only at R‑values/U‑factors and ignoring QII. The prescriptive tables can require both R‑value minimums and QII field verification as separate obligations — both must be met where shown.
  • Failing to schedule field verification early. QII field verification (per RA3.5) is an on‑site process; failing to coordinate inspections can delay final compliance documentation. (The code requires field verification procedures to be followed where QII is required.)
  • Citing RA3.5 acceptance numbers from memory. The specific pass/fail criteria, sample sizes, and measurement methods live in RA3.5; don’t rely on recollection — consult the appendix.

Worked example — new single‑family house using the prescriptive path

Scenario

  • New single‑family dwelling in Climate Zone X (example). The designer selects the prescriptive envelope from Table 150.1‑A. The table shows ceiling insulation = R‑38 and a QII flag = required for the ceiling entry.

What the code requires (process steps)

  1. The installer must install ceiling insulation that meets the R‑value (R‑38) and also install it to the QII acceptance criteria referenced by the prescriptive table. The prescriptive requirement is stated in § 150.1(c)E which cross‑references Reference Appendix RA3.5 for acceptance.
  2. Because the table flagged the assembly as QII required, the builder schedules field verification per RA3.5 before the project is signed off. That verification typically includes on‑site inspection(s) and any measurement or sampling that RA3.5 prescribes (sample sizes, inspection points, documentation). The code text directs you to RA3.5 for the exact procedures and pass/fail criteria; the prescriptive section itself requires using RA3.5 when QII is required. file
  3. The installer (or verified agent) completes the RA3.5 checklists and the required Certificate(s) of Verification as described elsewhere in the code and appendices, and those certificates are included with the permit/inspection package for final compliance. (The field‑verification framework and certificates are addressed by the Residential Reference Appendices.)

Numbers note: the prescriptive table gives R‑values; the code requires following RA3.5 for sampling/acceptance — the specific sample sizes and pass thresholds are in RA3.5, which must be consulted directly (RA3.5 text was not in the uploaded files I searched).

Related provisions

  • § 150.1(c)E — QII requirement and cross‑reference to Reference Appendix RA3.5 (prescriptive tables).
  • § 150.1(b) — Field verification rules and when installed features must be field‑verified (QII field verification is handled under the field‑verification rules and RA3.5).
  • § 170.2(a)6 — Multifamily prescriptive requirement referencing QII and RA3.5 for buildings up to three habitable stories.
  • Additions / alterations sections in Part 150.2 — contain exceptions for small additions and state when QII does not apply to additions (see the additions/alterations text and exceptions).

Code references

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

  • § 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.

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    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.

  • § 150.1 High relevance — show source text

    viii. Building enclosure air leakage. When performance compliance requires a building enclosure leakage rate that is lower than the standard design, the building enclosure shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.8. ix. Quality Insulation Installation (QII). When performance compliance requires field verification of QII, the building insulation system shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.5.

    (c) Prescriptive standards/component packages. Buildings that comply with the prescriptive standards shall be designed, constructed and equipped to meet all of the requirements for the appropriate climate zone shown in Table 150.1-A. In Table 150.1-A, an NA (not allowed) means that feature is not permitted in a particular climate zone and an NR (no requirement) means that there is no prescriptive requirement for that feature in a particular climate zone. Installed components shall meet the following requirements:

    1. Insulation.

    A. Roof and ceiling insulation shall be installed with an R -value equal to or greater than that shown in Table 150.1-A meeting Option i, ii or iii below. i. Option A: Reserved. ii. Option B: A minimum R -value of insulation in a ventilated attic 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 150.1(c)9A; or iii. Option C: A minimum R -value of ceiling insulation located between a ventilated attic and the conditioned space or within a cathedral ceiling assembly shall comply with Section 150.1(c)9B.

    B. Walls.

    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.

  • § 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.

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    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.

  • § 170.2 High relevance — show source text
    1. Floors shall meet the following requirements: A. Raised floors shall be insulated such that the floor assembly has an assembly U -factor equal to or less than shown in Table 170.2-A, or shall be insulated between wood framing with insulation having an R -value equal to or greater than shown in Table 170.2-A.

    B. Slab floors shall have perimeter insulation installed with a U -factor equal to or less than or R -value equal to or greater than shown in Table 170.2-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 170.2(a)5: Raised-floor insulation may be omitted if the foundation walls are insulated to meet the wall insulation minimums shown in Table 170.2-A.

    1. All buildings up to three habitable stories shall comply with the quality insulation installation (QII) requirements shown in Table 170.2-A. When QII is required, insulation installation shall meet the criteria specified in Reference Appendix RA3.5. Exception to Section 170.2(a): The insulation requirements of Table 170.2-A and Table 170.2-B may 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.

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    TABLE 170.2-A—ENVELOPE COMPONENT PACKAGE-MULTIFAMILY STANDARD BUILDING DESIGN Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10 Col11 Col12 Col13 Col14 Col15 Col16 Col17
    BUILDING COMPONENT -
    ROOFS AND CEILINGS    		 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
    Option B9 Below Roof Deck
    Insulation1,
  • § 4.4.3. High relevance — show source text

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    Reference Manual, the system shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.4.4.3. iii. Low leakage air handler. When performance compliance requires installation of a low leakage air-handling unit, the installed air-handling unit shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.1.4.3.9.

    iv. Reserved.

    v. Heat pump — rated heating capacity. When performance compliance requires installation of a heat pump system, the heating capacity values at 47°F and 17°F shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.4. vi. Whole-house fan. When performance compliance requires installation of a whole-house fan, the whole-house fan ventilation airflow rate and fan efficacy shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.9. vii. Central fan ventilation cooling system. When performance compliance requires installation of a central fan ventilation cooling system, the installed system shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.3.4. viii. Building enclosure air leakage. When performance compliance requires a building enclosure leakage rate that is lower than the standard design, the building enclosure shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.8. ix. Quality Insulation Installation (QII). When performance compliance requires field verification of QII, the building insulation system shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.5.

    (c) Prescriptive standards/component packages. Buildings that comply with the prescriptive standards shall be designed, constructed and equipped to meet all of the requirements for the appropriate climate zone shown in Table 150.1-A. In Table 150.1-A, an NA (not allowed) means that feature is not permitted in a particular climate zone and an NR (no requirement) means that there is no prescriptive requirement for that feature in a particular climate zone. Installed components shall meet the following requirements:

    1. Insulation.

    A. Roof and ceiling insulation shall be installed with an R -value equal to or greater than that shown in Table 150.1-A meeting Option i, ii or iii below. i. Option A: Reserved. ii. Option B: A minimum R -value of insulation in a ventilated attic 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 150.1(c)9A; or iii. Option C: A minimum R -value of ceiling insulation located between a ventilated attic and the conditioned space or within a cathedral ceiling assembly shall comply with Section 150.1(c)9B.

    B. Walls.

  • § 170.2 High relevance — show source text

    iv. Haze value. Have a glazing material or diffuser that has a measured haze value greater than 90 percent, determined according to ASTM D1003 or other test method approved by the Energy Commission. Exception to Section 170.2(a)3Biv: Skylights designed and installed to exclude direct sunlight entering the occupied space by the use of fixed or automated baffles or the geometry of the skylight and light well. 4. All exterior doors, excluding glazed doors, that separate conditioned space from unconditioned space or from ambient air shall have a U -factor not greater than the applicable value in Table 170.2-A. Glazed doors must comply with the requirements of Section 170.2(a)3A. Exception to Section 170.2(a)4: Swinging doors that are required to have fire protection are not required to meet the applicable door value in Table 170.2-A. 5. Floors shall meet the following requirements: A. Raised floors shall be insulated such that the floor assembly has an assembly U -factor equal to or less than shown in Table 170.2-A, or shall be insulated between wood framing with insulation having an R -value equal to or greater than shown in Table 170.2-A.

    B. Slab floors shall have perimeter insulation installed with a U -factor equal to or less than or R -value equal to or greater than shown in Table 170.2-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 170.2(a)5: Raised-floor insulation may be omitted if the foundation walls are insulated to meet the wall insulation minimums shown in Table 170.2-A.

    1. All buildings up to three habitable stories shall comply with the quality insulation installation (QII) requirements shown in Table 170.2-A. When QII is required, insulation installation shall meet the criteria specified in Reference Appendix RA3.5. Exception to Section 170.2(a): The insulation requirements of Table 170.2-A and Table 170.2-B may 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.

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    |TABLE 170.

  • § 4.4.2. High relevance — show source text

    When performance compliance requires installation of a heat pump system, the heating capacity values at 47°F and 17°F shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.4.4.2. F. Dwelling unit enclosure air leakage. When performance compliance requires a building enclosure leakage rate that is lower than the standard design, the building enclosure shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.8. G. Quality insulation installation (QII). When performance compliance requires field verification of QII, the building insulation system shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.5.

    NOTE: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code . Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5, 25402.8 and 25943, Public Resources Code .

    SECTION 170.2—PRESCRIPTIVE APPROACH

    Multifamily buildings, including both dwelling units and common use areas, that comply with the prescriptive standards shall be designed, constructed and equipped to meet all of the requirements for the appropriate climate zone shown in Table 170.2-A. In Table 170.2-A, NA (not allowed) means that feature is not permitted in a particular climate zone and NR (no requirement) means that there is no prescriptive requirement for that feature in a particular climate zone. Installed components shall meet the following requirements:

    (a) Envelope component requirements .

    1. Exterior roofs and ceilings . Exterior roofs and ceilings shall comply with each of the applicable requirements in this subsection:

    A. Roofing products. All roofing products shall meet the requirements of Section 110.8 and the applicable minimum aged solar reflectance and thermal emittance requirements of Table 170.2-A. Exception 1 to Section 170.2(a)1A: Roof area covered with building integrated photovoltaic panels and building integrated solar thermal panels are not required to comply with the minimum requirements for solar reflectance and thermal emittance or SRI.

    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 .

    1. Wall insulation.
  • § 150.0 High relevance — show source text

    Exception to Section 150.0(i)2A, B, and C: Where supplementary heat is locked out above 35°F by another control device in accordance with Section 150.0(h)7.

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    Exception 1 to Section 150.0(i)2: Systems compliant with Exception 1 to Section 150.0(h)7.

    Exception 2 to Section 150.0(i)2: Room air-conditioner heat pumps.

    (j) Insulation for piping and tanks.

    1. Water piping, solar water-heating system piping, and space-conditioning system line insulation thickness and conductivity. Piping shall be insulated as follows: A. All domestic hot water piping shall be insulated as specified in Section 609.12 of the California Plumbing Code . B. Piping for space-conditioning systems, solar water-heating system collector loop, and distribution piping for steam and hydronic heating system shall meet the requirements of Section 120.3(a). Exception 1 to Section 150.0(j)1: Factory-installed piping within space-conditioning equipment certified under Section 110.1 or 110.2.

    Exception 2 to Section 150.0(j)1: Piping that penetrates framing members shall not be required to have pipe insulation for the distance of the framing penetration. Piping that penetrates metal framing shall use grommets, plugs, wrapping or other insulating material to assure that no contact is made with the metal framing. Insulation shall butt securely against all framing members. Exception 3 to Section 150.0(j)1: Piping installed in interior or exterior walls shall not be required to have pipe insulation if all of the requirements are met for compliance with quality insulation installation (QII) as specified in the Reference Residential Appendix RA3.5. Exception 4 to Section 150.0(j)1: Piping surrounded with a minimum of 1 inch of wall insulation, 2 inches of crawlspace insulation, or 4 inches of attic insulation shall not be required to have pipe insulation. 2. Insulation protection. Pipe insulation shall meet the insulation protection requirements of Section 120.3(b).

    (k) Residential lighting.

    1. Luminaire requirements. A. Luminaire efficacy. All installed luminaires and light sources shall comply with Reference Joint Appendix JA8 and shall be certified and marked as required by JA8. Exception 1 to Section 150.0(k)1A: Integrated device lighting. Lighting integral to exhaust fans, kitchen range hoods, bath vanity mirrors, garage door openers, and ceiling fan kits that are subject to DOE’s Appliance and Equipment Standards Program. Exception 2 to Section 150.0(k)1A: Navigation lighting rated less than 5 watts, such as night lights, step lights, and path lights. Exception 3 to Section 150.0(k)1A: Lighting with an efficacy of 45 lumens per watt or greater and located internal to drawers, cabinetry, or linen closets. Exception 4 to Section 150.0(k)1A: Light sources as follows: i. LED light sources installed outdoors; ii. Inseparable solid state lighting (SSL) luminaires containing colored light sources that are installed to provide decorative lighting; iii.
  • § 170.2 High relevance — show source text

    A. EER2/SEER2/CEER/HSPF2 Rating. When performance compliance requires installation of a space-conditioning system with a rating that is greater than the minimum rating required by Table 170.2-K or specified for the standard

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    MULTIFAMILY BUILDINGS—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES

    design, the installed system shall be field verified in accordance with the procedures specified in the applicable sections of Reference Residential Appendix RA3. B. Variable capacity heat pump (VCHP) compliance option. When performance compliance requires installation of a heat pump system that meets all the requirements of the VCHP compliance option specified in the ACM Reference Manual, the system shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.4.4.3.

    C. Low leakage air handler. When performance compliance requires installation of a low leakage air-handling unit, the installed air handling unit shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.1.4.3.9. D. Thermal balancing valve. When performance compliance requires installation of thermal balancing valves with variable speed circulation pump(s), the installation shall meet the procedures specified in Reference Residential Appendix RA4.4.3. E. Heat pump—rated heating capacity. When performance compliance requires installation of a heat pump system, the heating capacity values at 47°F and 17°F shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.4.4.2. F. Dwelling unit enclosure air leakage. When performance compliance requires a building enclosure leakage rate that is lower than the standard design, the building enclosure shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.8. G. Quality insulation installation (QII). When performance compliance requires field verification of QII, the building insulation system shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.5.

    NOTE: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code . Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5, 25402.8 and 25943, Public Resources Code .

    SECTION 170.2—PRESCRIPTIVE APPROACH

    Multifamily buildings, including both dwelling units and common use areas, that comply with the prescriptive standards shall be designed, constructed and equipped to meet all of the requirements for the appropriate climate zone shown in Table 170.2-A. In Table 170.2-A, NA (not allowed) means that feature is not permitted in a particular climate zone and NR (no requirement) means that there is no prescriptive requirement for that feature in a particular climate zone. Installed components shall meet the following requirements:

    (a) Envelope component requirements .

    1. Exterior roofs and ceilings . Exterior roofs and ceilings shall comply with each of the applicable requirements in this subsection:
  • § 10-103 High relevance — show source text
    1. Compliance demonstration requirements for performance standards. A. Certificate of compliance and application for a building permit. The application for a building permit shall include documentation pursuant to Sections 10-103(a)1 and 10-103(a)2 which demonstrates, using an approved calculation method, that the building has been designed so that its energy consumption does not exceed the standard design energy budgets for the applicable climate zone. Exception to Section 150.1(b)2A Multiple orientation: A permit applicant may demonstrate compliance with the energy budget requirements of Section 150.1(a) and (b) for any orientation of the same building model if the documentation demonstrates that the building model with its proposed designs and features would comply in each of the four cardinal orientations.

    B. Field verification. When performance of installed features, materials, components, manufactured devices or systems above the minimum specified in Section 150.1(c) is necessary for the building to comply with Section 150.1(b), or is necessary to achieve a more stringent local ordinance, field verification shall be performed in accordance with the applicable requirements in the following subsections, and the results of the verification(s) shall be documented on applicable certificates of installation pursuant to Section 10-103(a)3 and applicable certificates of verification pursuant to Section 10-103(a)5. i. EER2/SEER2/CEER/HSPF2 Rating. When performance compliance requires installation of a space-conditioning system with a rating that is greater than the minimum rating required by Table 150.1-A or specified for the standard design, the installed system shall be field verified in accordance with the procedures specified in the applicable sections of Reference Residential Appendix RA3.4. ii. Variable capacity heat pump (VCHP) compliance option. When performance compliance requires installation of a heat pump system that meets all the requirements of the VCHP compliance option specified in the ACM

    2025 CALIFORNIA ENERGY CODE 177

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    SINGLE-FAMILY RESIDENTIAL BUILDINGS—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES

    Reference Manual, the system shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.4.4.3. iii. Low leakage air handler. When performance compliance requires installation of a low leakage air-handling unit, the installed air-handling unit shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.1.4.3.9.

    iv. Reserved.

    v. Heat pump — rated heating capacity. When performance compliance requires installation of a heat pump system, the heating capacity values at 47°F and 17°F shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.4. vi. Whole-house fan. When performance compliance requires installation of a whole-house fan, the whole-house fan ventilation airflow rate and fan efficacy shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.9. vii. Central fan ventilation cooling system. When performance compliance requires installation of a central fan ventilation cooling system, the installed system shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.3.4. viii. Building enclosure air leakage. When performance compliance requires a building enclosure leakage rate that is lower than the standard design, the building enclosure shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.8. ix. **Quality Insulation Installation (QII).

  • § 0.23 High relevance — show source text

    iii. Alterations that add fenestration area shall have a maximum SHGC value of 0.23 in Climate Zone 15.

    iv. When existing siding of a wood-framed wall is not being removed or replaced, cavity insulation of R-15 in a 2 × 4 framing and R-21 in a 2 × 6 framing shall be installed and continuous insulation is not required. v. Additions that consist of the conversion of existing spaces from unconditioned to conditioned space shall not be required to perform the following as part of QII: a. Existing window and door headers shall not be required to be insulated. b. Air sealing shall not be required when the existing air barrier is not being removed or replaced. B. Additions that are 700 square feet or less shall meet the requirements of Section 150.1(c), with the following modifications: i. Roof and ceiling insulation in a ventilated attic shall meet one of the following requirements: a. In Climate Zones 1, 2, 4, and 8 through 16, achieve an overall assembly U -factor not exceeding 0.025. In wood framed assemblies, compliance with U -factors may be demonstrated by installing insulation with an R -value of R-38 or greater. b. In Climate Zones 3, and 5 through 7, achieve an overall assembly U -factor not exceeding 0.031. In wood framed assemblies, compliance with U -factors may be demonstrated by installing insulation with an R value of R-30 or greater.

    ii. Radiant barriers shall be installed in Climate Zones 2-15.

    iii. Extensions of existing wood-framed walls may retain the dimensions of the existing walls and shall install cavity insulation of R-15 in a 2 × 4 framing and R-21 in a 2 × 6 framing. iv. In Climate Zones 2, 4 and 6-15; the maximum allowed west-facing fenestration area shall not be greater than 60 square feet; and shall also comply with either a or b below: a. For additions that are 700 square feet or less but greater than 400 square feet, the maximum allowed fenestration area limit is the greater of 120 square feet or 25 percent of the conditioned floor area of the addition. b. For additions that are 400 square feet or less, the maximum allowed fenestration area is the greater of 75 square feet or 30 percent of the conditioned floor area of the addition. v. Quality Insulation Installation (QII) requirements of Section 150.1(c)1E do not apply. vi. When existing siding of a wood-framed wall is not being removed or replaced, cavity insulation of R-15 in a 2 × 4 framing and R-21 in a 2 × 6 framing shall be installed and continuous insulation is not required.

    2025 CALIFORNIA ENERGY CODE 187

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

    Exception to Section 150.2(a)1B: Insulation in an enclosed rafter ceiling shall meet the requirements of Section 150.0. C. Mechanical ventilation for indoor air quality. Additions to existing buildings shall comply with Section 150.0(o) subject to the requirements specified in Subsections i and ii below. i. **Whole-dwelling unit mechanical ventilation.

  • § 0.025. High relevance — show source text

    i. Roof and ceiling insulation in a ventilated attic shall meet one of the following requirements: a. In Climate Zones 1, 2, 4, and 8 through 16, achieve an overall assembly U -factor not exceeding 0.025. In wood framed assemblies, compliance with U -factors may be demonstrated by installing insulation with an R -value of R-38 or greater.

    2025 CALIFORNIA ENERGY CODE 271

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

    MULTIFAMILY BUILDINGS—ADDITIONS, ALTERATIONS AND REPAIRS TO EXISTING MULTIFAMILY BUILDINGS

    b. In Climate Zones 3 and 5 through 7, achieve an overall assembly U- factor not exceeding 0.031. In wood framed assemblies, compliance with U- factors may be demonstrated by installing insulation with an R- value of R-30 or greater. ii. Radiant barrier. For buildings three habitable stories or less, radiant barriers shall be installed in attics with exposed attic deck undersides in Climate Zones 2–15. iii. Extensions of existing wood-framed walls may retain the dimensions of the existing walls and shall install cavity insulation of R-15 in a 2x4 framing and R-21 in a 2x6 framing; and iv. Fenestration products must meet the U- factor, RSGHC and VT requirements of Table 180.2-B. v. Quality insulation installation (QII) requirements of Section 170.2(a)6 do not apply. Exception to Section 180.1(a)1B: Insulation in an enclosed rafter ceiling shall meet the requirements of Section 160.1(a). Exception to Section 180.1(a)1: Additions that increase the area of the roof by 2,000 square feet or less are not required to comply with the solar ready requirements of Section 160.8. 2. Mechanical ventilation for indoor air quality. Additions to existing buildings shall comply with Section 160.2 subject to the requirements specified in Subsections A and B below. When field verification and diagnostic testing are required by Section 180.1(a)2, buildings with three habitable stories or fewer shall use the applicable procedures in the Residential Appendices, and buildings with four or more habitable stories shall use the applicable procedures in Nonresidential Appendices NA1 and NA2.

    Exception to Section 180.1(a)2: A dwelling unit air leakage test is not required for additions. A. Whole-dwelling unit mechanical ventilation . i. Dwelling units that meet the conditions in Subsection a or b below shall not be required to comply with the whole-dwelling unit ventilation airflow specified in Section 160.2(b)2Aiv or 160.2(b)2Av. a. Additions to an existing dwelling unit that increase the conditioned floor area of the existing dwelling unit by less than or equal to 1,000 square feet. b. Junior accessory dwelling units (JADU) that are additions to an existing building. ii. Additions to an existing dwelling unit that increase conditioned floor area by more than 1,000 square feet shall have mechanical ventilation airflow in accordance with Section 160.2(b)2Aiv or 160.2(b)2Av, as applicable. The mechanical ventilation airflow rate shall be based on the conditioned floor area of the entire dwelling unit comprising the existing dwelling unit conditioned floor area plus the addition conditioned floor area.

  • § 110.8 High relevance — show source text
    1. Insulation installation must:

    A. Be covered with a solid guard that protects against damage from ultraviolet radiation, moisture, landscaping operation, equipment maintenance and wind; and B. Include a rigid plate, which penetrates the slab and blocks the insulation from acting as a conduit for insects from the ground to the structure above the foundation.

    TABLE 110.8-A—SLAB INSULATION REQUIREMENTS FOR HEATED SLAB-ON-GRADE Col2 Col3 Col4 Col5
    INSULATION
    LOCATION    		 INSULATION
    ORIENTATIO
    N    		 INSTALLATION REQUIREMENTS CLIMATE
    ZONE    		 INSULATION
    R-VALUE
    Outside edge of
    heated slab,
    either inside or
    outside the
    foundation wall    		 Vertical From the level of the top of the slab, down 16 inches or to the frost line,
    whichever is greater. Insulation may stop at the top of the footing where this
    is less than the required depth. For below grade slabs, vertical insulation shall
    be extended from the top of the foundation wall to the bottom of the
    foundation (or the top of the footing) or to the frost line, whichever is greater.    		 1–15 5
    Outside edge of
    heated slab,
    either inside or
    outside the
    foundation wall    		 Vertical From the level of the top of the slab, down 16 inches or to the frost line,
    whichever is greater. Insulation may stop at the top of the footing where this
    is less than the required depth. For below grade slabs, vertical insulation shall
    be extended from the top of the foundation wall to the bottom of the
    foundation (or the top of the footing) or to the frost line, whichever is greater.    		 16 10
    Between heated
    slab and outside
    foundation wall    		 Vertical and
    horizontal    		 Vertical insulation from top of slab at inside edge of outside wall down to
    the top of the horizontal insulation. Horizontal insulation from the outside
    edge of the vertical insulation extending 4 feet toward the center of the slab
    in a direction normal to the outside of the building in plan view.    		 1–15 5
    Between heated
    slab and outside
    foundation wall    		 Vertical and
    horizontal    		 Vertical insulation from top of slab at inside edge of outside wall down to
    the top of the horizontal insulation. Horizontal insulation from the outside
    edge of the vertical insulation extending 4 feet toward the center of the slab
    in a direction normal to the outside of the building in plan view.    		 16 10 vertical
    and
    7 horizontal

    2025 CALIFORNIA ENERGY CODE 57

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    ALL OCCUPANCIES—MANDATORY REQUIREMENTS FOR THE MANUFACTURE, CONSTRUCTION AND INSTALLATION OF SYSTEMS, EQUIPMENT AND BUILDING COMPONENTS

    (h) Wet insulation systems. When insulation is installed on roofs above the roofing membrane or layer used to seal the roof from water penetration, the effective R -value of the insulation shall be as specified in Reference Joint Appendix JA4.

  • § 1.1 Medium relevance — show source text

    1/2″ thick gypsum wall-
    board on both faces; insulated cavities.|See
    Note 17|45 min||1||17, 18,
    23|3/4| |W-4-W-35|41/2″|2″ × 4″ stud wall;1/2″ thick gypsum wall-
    board on both faces; insulated cavities.|N/A|1 hr||1||17, 18,
    24|1| |W-4-W-36|41/2″|2″ × 4″ stud wall;1/2″ thick, 1.1 lbs/ft2 wood
    fiberboard sheathing on both faces.|See
    Note 23|15 min||1||17, 23|1/4| |W-4-W-37|41/2″|2″ × 4″ stud wall;1/2″ thick, 0.7 lb./ft2 wood
    fiberboard sheathing on both faces.|See
    Note 23|10 min||1||17, 23|1/6| |W-4-W-38|41/2″|2″ × 4″ stud wall;1/2″ thick, flameproofed
    1.6 lbs/ft2 wood fiberboard sheathing on
    both faces.|See
    Note 23|30 min||1||17, 23|1/2| |W-4-W-39|41/2″|2″ × 4″ stud wall;1/2″ thick gypsum wall-
    board on both faces; insulated cavities.|See
    Note 23|1 hr||1||17, 18,
    23|1| |W-4-W-40|41/2″|2″ × 4″ stud wall;1/2″ thick, 1:2; 1:3 gypsum
    plaster on wood lath on both faces.|See
    Note 23|30 min||1||17, 21,
    23|1/2| |W-4-W-41|41/2″|2″ × 4″ stud wall;1/2″ thick, 1:2; 1:3 gypsum
    plaster on wood lath on both faces; insu-
    lated cavities.|See
    Note 23|1 hr||1||17, 18,
    21, 23|1| |W-4-W-42|41/2″|2″ × 4″ stud wall;1/2″, 1:5; 1:7.5 lime plas-
    ter on wood lath on both wall faces.|See
    Note 23|30 min||1||17, 21,
    23|1/2| |W-4-W-43|41/2″|2″ × 4″ stud wall;1/2″ thick 1:5; 1:7.5 lime
    plaster on wood lath on both faces; insu-
    lated cavities.|See
    Note 23|45 min||1||17, 18,
    21, 23|3/4| |W-4-W-44|45/8″|2″ × 4″ stud wall;3/16″ thick cement-asbes-
    tos over3/8″ thick gypsum board on both
    faces.|See
    Note 23|1 hr||1||23, 25,
    26,

  • § 2.95 Medium relevance — show source text

    00|2.95|2.20|1.45|3.00|2.35|1.25|DR| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#8 screw into 33 mil steel or
    thicker|8|3.00|2.55|1.60|0.60|3.00|1.80|DR|DR| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#8 screw into 33 mil steel or
    thicker|12|3.00|1.80|DR|DR|3.00|0.65|DR|DR| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 33 mil steel|6|4.00|3.50|2.70|1.95|4.00|2.90|1.70|0.55| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 33 mil steel|8|4.00|3.10|2.05|1.00|4.00|2.25|0.70|DR| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 33 mil steel|12|4.00|2.25|0.70|DR|3.70|1.05|DR|DR| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 43 mil steel or
    thicker|6|4.00|4.00|4.00|3.60|4.00|4.00|3.45|2.70| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 43 mil steel or
    thicker|8|4.00|4.00|3.70|3.00|4.00|3.85|2.80|1.80| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 43 mil steel or
    thicker|12|4.00|3.85|2.80|1.80|4.00|3.05|1.50|DR| |For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
    DR = design required, o.c. = on center.
    a. Cold-formed steel framing shall be minimum 33 ksi steel for 33 mil and 43 mil steel and 50 ksi steel for 54 mil steel or thicker.
    b. Screws shall comply with the requirements of AISI S240.
    c. Foam sheathing shall have a minimum compressive strength of 15 pounds per square inch in accordance with ASTM C578 or ASTM C1289.|For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
    DR = design required, o.c. = on center.
    a. Cold-formed steel framing shall be minimum 33 ksi steel for 33 mil and 43 mil steel and 50 ksi steel for 54 mil steel or thicker.
    b.

  • § 160.3 Medium relevance — show source text

    ii. For duct wrap, installed thickness shall be assumed to be 75 percent (25 percent compression) of nominal thickness.

    iii. For factory-made flexible air ducts, the installed thickness shall be determined by dividing the difference between the actual outside diameter and nominal inside diameter by two. F. Duct labeling. Insulated flexible duct products installed to meet this requirement shall include labels, in maximum intervals of 3 feet, showing the thermal performance R- value for the duct insulation itself (excluding air films, vapor retarder or other duct components), based on the tests in Section 160.3(b)5D and the installed thickness determined by Section 160.3(b)5Eiii. G. Backdraft dampers. All fan systems, regardless of volumetric capacity, that exchange air between the building conditioned space and the outside of the building shall be provided with backdraft or automatic dampers to prevent unintended air leakage through the fan system when the fan system is not operating. H. Gravity ventilation dampers. All gravity ventilating systems that serve conditioned space shall be provided with either automatic or readily accessible, manually operated dampers in all openings to the outside except combustion inlet and outlet air openings and elevator shaft vents. I. Protection of insulation. Insulation shall be protected from damage, including that due to sunlight, moisture, equipment maintenance and wind but not limited to the following: Insulation exposed to weather shall be suitable for outdoor service (e.g., protected by aluminum, sheet metal, painted canvas or plastic cover). Cellular foam insulation shall be protected as above or painted with a coating that is water retardant and provides shielding from solar radiation that can cause degradation of the material. J. Porous inner core flex duct. Flexible ducts having porous inner cores shall have a nonporous layer or air barrier between the inner core and the outer vapor barrier. K. Duct system sealing and leakage testing. When space-conditioning systems utilize forced air duct systems to supply conditioned air to an individual dwelling unit, the ducts shall be sealed, as confirmed through field verification and diagnostic testing, in accordance with all applicable procedures specified in Reference Residential Appendix RA3.1. Air handler airflow for calculation of duct leakage rate compliance targets shall be determined according to methods specified in Reference Residential Appendix RA3.1.4.2. For multifamily dwellings with the air-handling unit installed and the ducts connected directly to the air handler, regardless of duct system location: i. The total leakage of the duct system shall not exceed 12 percent of the air handler airflow as determined utilizing the procedures in Reference Residential Appendix Section RA3.1.4.3.1; or ii. The duct system leakage to outside shall not exceed 6 percent of the air handler airflow as determined utilizing the procedures in Reference Residential Appendix Section RA3.1.4.3.4.

    • Exception 1 to Section 160.3(b)5K: The field verification and ECC-Provider data registry requirements of Reference Residential Appendix RA2 and RA3 are not required for multifamily dwelling units in buildings four

    216 2025 CALIFORNIA ENERGY CODE

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    MULTIFAMILY BUILDINGS—MANDATORY REQUIREMENTS

    habitable stories and greater. The installer shall certify that diagnostic testing was performed in accordance with the applicable procedures. Exception 2 to Section 160.3(b)5K: Multifamily dwelling units in buildings four habitable stories and greater in Climate Zones 1, 3, 5 and 7. L.

  • § 1.1.4 Medium relevance — show source text

    see Notes 2, 18, 26, 34, 40;
    facings: side 1; see Note 38.|80 psi|5 hrs||1||1, 20|5| |W-8-M-91|81/2″|Cored concrete masonry; see Notes 2, 19, 26, 31, 40;
    facings: fire side only; see Note 38.|80 psi|1 hr
    45 min||1||1, 20|13/4| |W-8-M-92|81/2″|Cored concrete masonry; see Notes 2, 18, 26, 31, 40;
    facings: one side; see Note 38.|80 psi|4 hrs||1||1, 20|4|

    2025 CALIFORNIA EXISTING BUILDING CODE RESOURCE A-37

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

    RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

    TABLE 1.1.4—continued
    MASONRY WALLS
    8″ TO LESS THAN 10″ THICK    		 Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10
    ITEM CODE THICKNESS CONSTRUCTION DETAILS PERFORMANCE PERFORMANCE REFERENCE NUMBER REFERENCE NUMBER REFERENCE NUMBER NOTES REC.
    HOURS
    ITEM CODE THICKNESS CONSTRUCTION DETAILS LOAD TIME PRE-
    BMS-92    		 BMS-92 POST-
    BMS-92    		 POST-
    BMS-92    		 POST-
    BMS-92
    W-8-M-93 81/2″ Cored concrete masonry; see Notes 2, 19, 26, 36, 41;
    facings: fire side only; see Note 38.    		 80 psi 2 hrs 1 1, 20 2
    W-8-M-94 81/2″ Cored concrete masonry; see Notes 2, 18, 26, 36, 41;
    facings: fire side only; see Note 38.    		 80 psi 4 hrs 1 1, 20 4
    W-8-M-95 81/2″ Cored concrete masonry; see Notes 2, 19, 26, 34, 41;
    facings: fire side only; see Note 38.    		 80 psi 1 hr
    30
    min    		 1 1, 20 11/2
    W-8-M-96 81/2″ Cored concrete masonry; see Notes 2, 18, 26, 34, 41;
    facings: one side; see Note 38.    		 80 psi 3 hrs 1, 20 3
    W-8-M-97 81/2″ Cored concrete masonry; see Notes 2, 19, 26, 29, 41;
    facings: fire side only; see Note 38.

Frequently asked questions

What document contains the step‑by‑step acceptance tests for QII?

The acceptance tests, sample sizes and field procedures are in Reference Residential Appendix RA3.5; the prescriptive sections in § 150.1(c)E and the multifamily section § 170.2(a)6 explicitly point you to RA3.5 for the criteria. file

If Table 150.1‑A shows an R‑value but no QII flag, do I still need RA3.5?

No — RA3.5 applies when the prescriptive table or the compliance path specifically requires QII or when the performance path requires field verification of insulation. If the table entry does not flag QII, follow the normal installation and documentation requirements in the body of the code.

Do additions always need QII?

Not always. The additions and alterations sections include exceptions for some small additions (for example, some provisions for additions ≤ 700 ft²) where QII requirements of §150.1(c)1E may not apply — check the additions wording in the code.

Where do I record the QII field verification?

Field verification and the results are documented on the applicable certificates of installation and verification required by the code and the Residential Reference Appendices; RA3.5 describes the verification procedures you must follow when QII is required.

I need the numeric sampling thresholds in RA3.5 — can you list them here?

I cannot list RA3.5 numeric thresholds because the RA3.5 appendix text was not present in the uploaded files I searched. To get exact sampling rates, acceptance thresholds and measurement procedures, consult the full Reference Residential Appendix RA3.5 in the official code document.

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