CRC · California Residential Code
Key Title 24 Part 6 references cited by residential code
If you take the performance route for a California residence, use Energy Commission‑certified compliance software (see **§ 100.1**) and demonstrate your design meets the Part 6 energy budget / LSC rules (see **§ 150.1(b)**). Appendices in the CRC/CalGreen point back to these two Part 6 sections for computing LSC margins, field verification, and required documentation.
Last reviewed: July 6, 2026
What the code requires — plain English (controlling §)
Residential projects in California must follow the California Energy Code (Title 24, Part 6) for energy conservation whenever the Residential Code defers energy rules to Part 6. In particular, when the residential code or related local voluntary measures use the performance approach they require use of Commission‑certified compliance software as defined in § 100.1, and they rely on the performance (energy budget / LSC) rules in § 150.1(b) of Part 6 for demonstrating compliance. The Residential Code notes that Part IV (energy) is not adopted in the CRC and directs users to Part 6 for mandatory energy rules.
The single most important rule: use Energy Commission‑certified compliance software for any performance approach submittal (see § 100.1) and meet the energy budget / LSC requirements (see § 150.1(b)).
Requirements in detail
1) Which Part 6 rules the Residential Code points to
- The CRC explicitly defers energy conservation mandatory requirements to the California Energy Code (Title 24, Part 6) — Part IV of the CRC is not adopted and users are told to use Part 6. (CRC: Part IV—Energy Conservation — note).
- Voluntary residential measures that are codified in the Green Building Standards (Appendix A4) also require that LSC ratings be computed by compliance software certified under § 100.1, and that the energy performance demonstration follow § 150.1(b). See Appendix A4 references to Part 6 Sections 100.1 and 150.1(b).
2) What § 100.1 (Compliance software / definitions) controls
- § 100.1 (definitions / scope around compliance tools) identifies and links the term COMPLIANCE SOFTWARE and the approval pathway for software used to demonstrate performance compliance. The CRC/Appendices require that performance demonstrations use Commission‑approved software per § 100.1.
3) What § 150.1(b) (Performance approach: Energy budget and LSC) controls
- § 150.1(b) defines the performance approach, the energy budget (expressed in source energy and Long‑Term System Cost — LSC) and describes how to demonstrate compliance with the performance standard. It also requires documentation, permit submittal rules, and when field verification is required for installed features that perform above the minimums.
Decision-relevant table
| Decision / item | When it applies | Required value / action | Code Reference |
|---|---|---|---|
| Use of compliance software | Any performance‑approach submittal | Use Commission‑certified compliance software approved per § 100.1 | § 100.1 — see Commission software definition and approval rules |
| Energy budget method (performance) | Applicant elects performance approach instead of prescriptive | Demonstrate proposed design ≤ standard design energy budget (source energy and LSC); compute via certified software | § 150.1(b) — performance approach, energy budget and LSC defined |
| LSC margin for voluntary A4 performance (example) | When using Appendix A4 performance margins | Reduce required LSC in the certified software by the climate‑zone margin in Table A4.203.1.1 (e.g., CZ 3 = 1.10) and include rating in Certificate of Compliance | Appendix A4 — Table A4.203.1.1 and A4.203.1.1 text referencing § 100.1 and § 150.1(b) |
| Field verification | When installed features above minima are needed to meet performance target | Perform field verification and document results per the referenced RA (Residential Appendices) procedures (e.g., RA3.x as identified in § 150.1(b)) | § 150.1(b) — field verif. and RA references |
| Duct & envelope measures cited in Appendix A4 | Voluntary prerequisites / alterations | Options include R‑19 below roof deck, R‑8 continuous above-deck, or ducts/air handlers in conditioned space; or meet the RA3.1 duct criteria | Appendix A4 (A4.203.1.2.1) citing § 150.1(c)9A/B and RA3.1 |
Exceptions & special cases
- Community/shared options (community solar, community BESS) approved under Part 1 (Section 10‑115) may be used to meet some performance goals — Part 6 recognizes a Commission‑approved community shared offset option as an exception in § 150.1(b).
- Appendix A4 voluntary measures are optional local adoptions; if a local jurisdiction makes them mandatory it must follow the Energy Commission filing process (Part 1 rules). The appendix text explicitly ties its LSC computation back to § 100.1 and § 150.1(b) and requires the rating be shown on the Certificate of Compliance.
- Field verification is required only when installed performance above Part 6 minimums is necessary to meet the energy budget (see § 150.1(b)2B); otherwise standard documentation from the compliance software may suffice.
Common mistakes
- Using non‑certified or unapproved software for a performance demonstration — always confirm the software is Commission‑certified per § 100.1.
- Forgetting field verification when the performance case depends on higher‑than‑minimum installed performance (leads to failed inspections) — § 150.1(b) requires field verification and RA procedures in that circumstance.
- Misapplying Appendix A4 LSC margins as automatic credits in the compliance software without documenting the LSC rating on the Certificate of Compliance (Appendix A4 requires the rating be included).
- Applying prescriptive Part 6 requirements from other occupancies (non‑residential tables) to low‑rise residential without checking Part 6 scope and the residential RA appendices. Always use the residential RA references when the CRC or appendices call them out.
Worked example — concrete scenario with numbers (illustrative)
Scenario: New single‑family home in Climate Zone 3 elects the Appendix A4 performance pathway.
Appendix A4 Table A4.203.1.1 gives a Total LSC compliance margin = 1.10 for Climate Zone 3. The appendix requires the LSC rating be computed in Commission‑certified compliance software as specified in § 100.1, and that the rating reduce the minimum performance‑based LSC requirement by the margin.
Suppose the compliance software reports the minimum LSC for the standard design is 10.00 LSC units (software output — hypothetical for illustration). The Appendix requires reducing that minimum by the margin 1.10:
- Required Proposed Design LSC ≤ 10.00 − 1.10 = 8.90 (LSC units). (This arithmetic follows the Appendix A4 instruction to reduce the LSC required by the margin; the actual units and software output are from the certified compliance tool.)
If the proposed design relies on higher‑efficiency HVAC or special envelope features above Part 6 minimums to reach 8.90, then per § 150.1(b) the installer must perform the applicable field verification tests (and document them using the RA procedures) before final compliance can be accepted.
Note: the numerical “10.00” is an example. Actual LSC values come from the Commission‑certified compliance software; the required step is to reduce the software’s minimum LSC by the climate‑zone margin from Appendix A4 and document the rating on the Certificate of Compliance.
Related provisions (CRC / adjacent code sections)
- Part IV — Energy Conservation (CRC note: Part IV is not adopted; users must use the California Energy Code, Title 24, Part 6).
- Appendix A4 (Residential Voluntary Measures) — A4.203.1.1 (LSC / performance approach referencing § 100.1 and § 150.1(b)) — see Appendix A4 text and Table A4.203.1.1.
- Appendix A4 — A4.203.1.2.1 (roof deck insulation / ducts in conditioned space options that point back to Part 6 § 150.1(c)9A/B and RA3.1).
- California Energy Code — § 150.1(b) (performance approach / energy budget / LSC rules and field verification requirements).
- California Energy Code — definition of COMPLIANCE SOFTWARE and the software approval mechanism (associated with § 100.1 definitions).
(These related items are cited because the Residential Code and the Green Building Appendix refer directly to Part 6 § 100.1 and § 150.1(b) for performance compliance and software requirements.)
Code references
Grounded in the retrieved California Residential Code — click a citation to read the verbatim passage:
CRC § 203.1.2 High relevance — show source text
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APPENDIX A4 — RESIDENTIAL VOLUNTARY MEASURES
A4.203.1.2 Prerequisite options. In addition, a minimum of TWO of the efficiency measures specified in Sections A4.203.1.2.1 through A4.203.1.2.7 must be met.
A4.203.1.2.1 Roof deck insulation, or ducts in conditioned space. Meet one of the three options for the location of ducts and air handlers as well as insulation R -values and installation of a radiant barrier as specified in Title 24, Part 6, Section 150.1(c)9A or B:
Below roof deck insulation with a minimum R -value of 19; or,
Continuous above deck insulation with a minimum R-8 and with an air space present between the roofing and the roof deck; or,
All ducts and air handlers in conditioned space as specified in the Title 24, Part 6, Reference Appendix RA3.1.
A4.203.1.2.2 High performance walls. Meet the climate zone dependent U -factor or insulation R -value for either 2x6 or 2x4 framing as specified in Title 24, Part 6, Section 150.1(c)1B: maximum U -factor of 0.048.
A4.203.1.2.3 Compact hot water distribution system. Meet the requirements for installation of Compact Hot Water Distribution Systems specified in the Title 24, Part 6, Reference Appendix RA3.6.5.
A4.203.1.2.4 Drain water heat recovery. Meet the requirements for installation of Drain Water Heat Recovery specified in Title 24, Part 6, Reference Appendix RA4.4.21.
A4.203.1.2.5 High performance vertical fenestration. Meet the climate zone dependent U -factor and Solar Heat Gain Coefficient (SHGC) as rated in accordance with Title 24, Part 6, Section 110.6, and shall have a maximum U -factor of 0.21 in Climate Zones 1 − 16, maximum SHGC of 0.23 in Climate Zones 2, 4, and 6 − 14, and maximum SHGC of 0.20 in Climate Zone 15.
Exception to A4.203.1.2.5: Fenestration in Climate Zones 1, 3, 5, and 16 is not required to comply with the maximum SHGC requirements.
A4.203.1.2.6 Heat pump water heater demand management. For buildings with heat pump water heating, meet the requirements for installation of controls specified by Title 24, Part 6, Reference Appendix JA13.3.3.
A4.203.1.2.7 Battery storage system controls. For buildings with battery storage systems, meet the requirements for installation of controls specified by Title 24, Part 6, Reference Appendix JA12 for either the Time-of-Use Control or Advanced Demand Flexibility Control option.
CRC § 204.1.1 High relevance — show source text
A4.204.1.1 Altered space-conditioning system serving existing single-family dwelling units – mechanical cooling. When a space-conditioning system serving an existing single-family dwelling unit is altered in Climate Zones 1 through 14 and 16 by installation or replacement of an air conditioner, the altered system shall comply with either a or b below in addition to the requirements for installation specified by Title 24, Part 6, Sections 150.2(b)1E and 150.2(b)1F: a. A heat pump shall be the primary heating source and sized according to the system selection requirements specified by Title 24, Part 6 of Section 150.0(h)5. Supplemental heating may be provided by an existing gas furnace or existing electric resistance heating; or b. An air conditioner shall meet the following requirements: i. R-8 duct insulation for ducts located in unconditioned space; and ii. The duct system measured air leakage shall be equal to or less than 5 percent of the system air handler airflow as confirmed through field verification and diagnostic testing, per the requirements in Title 24, Part 6, Reference Residential Appendix Section RA3.1.4.3.1; and iii. Demonstrate, in every control mode, airflow greater than or equal to 400 CFM per ton of nominal cooling capacity through the return grilles, and an air-handling unit fan efficacy less than or equal to 0.35 W/CFM. The airflow rate and fan efficacy requirements in this section shall be confirmed through field verification and diagnostic testing, following the procedures outlined in Title 24, Part 6, Reference Residential Appendix RA3.3; and iv. In all climate zones refrigerant charge verification requirements shall meet the requirements in Title 24, Part 6 Section 150.2(b)1Fiib; and v. Vented attics shall have insulation installed to achieve a U -factor of 0.020 or insulation installed at the ceiling level shall result in an insulated thermal resistance of R-49 or greater for the insulation alone; and vi. Air seal all accessible areas of the ceiling plane between the attic and the conditioned space in accordance with the requirements in Title 24, Part 6 Section 150.2(b)1Jii.
Exception 1 to Section A4.204.1.1: Where the capacity of the existing main electrical service panel is insufficient to supply the electrical capacity of a heat pump and where the existing main electrical service panel is sufficient to supply a new or replacement air conditioner, as calculated according to the requirements of California Electrical Code Article 220.83 or 220.87. Documentation of electrical load calculations in accordance with Article 220 must be submitted to the enforcement agency prior to permitting for both the heat pump and proposed air conditioner.
Exception 2 to Section A4.204.1.1: Where the required capacity of a heat pump to meet the system selection requirements of Section 150.0(h)5 is greater than or equal to 12,000 Btu/h more than the required capacity of an air conditioner to meet the design cooling load. Documentation of heating and cooling load calculations in accordance with 150.0(h) must be submitted to the enforcement agency prior to permitting for both the heat pump and proposed air conditioner.
A4.204.1.2 Altered pool and/or spa heating for existing multifamily buildings. Alteration of an existing multifamily pool and/or spa heating system shall meet the following:
Heating source sizing. Heating systems or equipment for pools or spas shall meet one of the sizing requirements of Items 1 through 5 below: 1.
CRC § 203.1.1 High relevance — show source text
A4.203.1.1 Long-term system cost (LSC). LSC rating for the building’s Proposed Design shall be computed by Compliance Software certified by the Energy Commission as specified in Title 24, Part 6, Section 100.1 and 150.1(b), and shall reduce the LSC required in the Compliance Software for minimum performance-based compliance with the California Energy Code by the compliance margin specified in Table A4.203.1.1. The rating shall be included in the Certificate of Compliance documentation.
TABLE A4.203.1.1—RECOMMENDED LSC MARGINS BY CLIMATE ZONES Col2 CALIFORNIA ENERGY CODE CLIMATE ZONE TOTAL LSC COMPLIANCE MARGIN 1 2.70 2 1.62 3 1.10 4 1.11 5 1.01 6 0.24 7 0.24 8 0.21 9 0.20 10 0.18 11 1.11 12 1.05 13 0.96 14 1.21 15 0.59 16 1.68 Note: Community shared options complying with Title 24, Part 1, Section 10-115 may be used to achieve LSC targets. Note: Community shared options complying with Title 24, Part 1, Section 10-115 may be used to achieve LSC targets. 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A4-9
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APPENDIX A4 — RESIDENTIAL VOLUNTARY MEASURES
A4.203.1.2 Prerequisite options. In addition, a minimum of TWO of the efficiency measures specified in Sections A4.203.1.2.1 through A4.203.1.2.7 must be met.
A4.203.1.2.1 Roof deck insulation, or ducts in conditioned space. Meet one of the three options for the location of ducts and air handlers as well as insulation R -values and installation of a radiant barrier as specified in Title 24, Part 6, Section 150.1(c)9A or B:
Below roof deck insulation with a minimum R -value of 19; or,
Continuous above deck insulation with a minimum R-8 and with an air space present between the roofing and the roof deck; or,
All ducts and air handlers in conditioned space as specified in the Title 24, Part 6, Reference Appendix RA3.1.
A4.203.1.2.2 High performance walls. Meet the climate zone dependent U -factor or insulation R -value for either 2x6 or 2x4 framing as specified in Title 24, Part 6, Section 150.1(c)1B: maximum U -factor of 0.048.
A4.203.1.2.3 Compact hot water distribution system. Meet the requirements for installation of Compact Hot Water Distribution Systems specified in the Title 24, Part 6, Reference Appendix RA3.6.5.
CRC § 100.1 Medium relevance — show source text
(d) Track lighting supplementary overcurrent protection panel. A Track Lighting Supplementary Overcurrent Protection Panel shall be used only for line-voltage track lighting and shall be recognized for compliance with Part 6 only if it meets all of the following requirements:
Shall be listed as defined in Section 100.1; and
Shall have a permanently installed label that is prominently located stating the following: “NOTICE: This Panel for Track Lighting Energy Code Compliance Only.” The overcurrent protection devices in this panel shall only be replaced with the same or lower amperage. No other overcurrent protective device shall be added to this panel. Adding to, or replacement of, existing overcurrent protective device(s) with higher continuous ampere rating will void the panel listing and require resubmittal of compliance documentation to the enforcement agency responsible for compliance with the California Title 24, Part 6 Building Energy Efficiency Standards.
SECTION 110.10—MANDATORY REQUIREMENTS FOR SOLAR READINESS
(a) Covered occupancies.
- Single-family residences. Single-family residences located in subdivisions with ten or more single-family residences and where the application for a tentative subdivision map for the residences has been deemed complete or approved by the enforcement agency, which do not have a photovoltaic system installed, shall comply with the requirements of Sections 110.10(b) through 110.10(e)
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ALL OCCUPANCIES—MANDATORY REQUIREMENTS FOR THE MANUFACTURE, CONSTRUCTION AND INSTALLATION OF SYSTEMS, EQUIPMENT AND BUILDING COMPONENTS
- Low-rise multifamily buildings. Low-rise multifamily buildings that do not have a photovoltaic system installed shall comply with the requirements of Sections 110.10(b) through 110.10(d).
- Hotel/motel occupancies and high-rise multifamily buildings. Hotel/motel occupancies and high-rise multifamily buildings with ten habitable stories or fewer, that do not have a photovoltaic system installed, shall comply with the requirements of Sections 110.10(b) through 110.10(d).
- Nonresidential buildings. Nonresidential buildings with three habitable stories or fewer, other than I-2 and I-2.1 buildings, that do not have a photovoltaic system installed, shall comply with the requirements of Sections 110.10(b) through 110.10(d).
(b) Solar zone.
- Minimum solar zone area. The solar zone shall have a minimum total area as described below. The solar zone shall comply with access, pathway, smoke ventilation and spacing requirements as specified in Title 24, Part 9 or other Parts of Title 24 or in any requirements adopted by a local jurisdiction. The solar zone total area shall be comprised of areas that have no dimension less than five feet and are no less than 80 square feet each for buildings with roof areas less than or equal to 10,000 square feet or no less than 160 square feet each for buildings with roof areas greater than 10,000 square feet. A. Single-family residences. The solar zone shall be located on the roof or overhang of the building and have a total area no less than 250 square feet. Exception 1 to Section 110.10(b)1A: Single-family residences with a permanently installed domestic solar waterheating system meeting the installation criteria specified in the Reference Residential Appendix RA4 and with a minimum solar savings fraction of 0.50.
CRC § 25218.5 Medium relevance — show source text
(b) Certification Requirements for Manufactured Systems, Equipment, Appliances and Building Components.
- Appliances that are within the scope of Section 1601 of the Appliance Efficiency Regulations shall only be installed if they have been certified to the Energy Commission by the manufacturer, pursuant to the provisions of Title 20 California Code of Regulations, Section 1606; or
- Systems, equipment, appliances and building components that are required by Part 6 or the Reference Appendices to be certified to the Energy Commission, which are not appliances that are within the scope of Section 1601 of the Appliance Efficiency Regulations, shall only be installed if they are certified by the manufacturer in a declaration, executed under penalty of perjury under the laws of the State of California, that: A. All the information provided pursuant to the certification is true, complete, accurate and in compliance with all applicable requirements of Part 6; and B. The equipment, product, or device was tested using the test procedure specified in Part 6 if applicable
- The certification status of any system, equipment, appliance or building component shall be confirmed only by reference to: A. A directory published or approved by the Commission; or B. A copy of the application for certification from the manufacturer and the letter of acceptance from the Commission staff; or C. Written confirmation from the publisher of a Commission-approved directory that a device has been certified; or D. A Commission-approved label on the device.
Note: Part 6 does not require a builder, designer, owner, operator, or enforcing agency to test any certified device to determine its compliance with minimum specifications or efficiencies adopted by the Commission.
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 110.1—MANDATORY REQUIREMENTS FOR APPLIANCES
(a) Any appliance regulated by the Appliance Efficiency Regulations, Title 20 California Code of Regulations, Section 1601 et seq., may be installed only if the appliance fully complies with Section 1608(a) of those regulations.
(b) Except for those circumstances described in Section 110.1(c), conformance with efficiency levels required to comply with Part 6 mandatory, prescriptive and performance standards shall be verified utilizing data from either:
- The Energy Commission’s database of certified appliances maintained pursuant to Title 20 California Code of Regulations Section 1606, and which is available at: www.energy.ca.gov/appliances/database/ ; or
- An equivalent directory published by a federal agency; or
- An approved trade association directory as defined in Title 20 California Code of Regulations Section 1606(h).
(c) Conformance with efficiency levels required to comply with Part 6 mandatory, prescriptive and performance standards shall be demonstrated either by default to the mandatory efficiency levels specified in Part 6 or by following procedures approved by the Commission pursuant to Section 10-109 of Title 24, Part 1, when:
- Data to verify conformance with efficiency levels required to comply with Part 6 mandatory, prescriptive and performance standards is not available pursuant to subdivision (b); or
- Field verification and diagnostic testing is required for compliance with Part 6 and the Energy Commission has not approved a field verification and diagnostic test protocol that is applicable to the appliance; or
CRC § 204.1 Medium relevance — show source text
- Lighting for industrial sites, including but not limited to, rail yards, maritime shipyards and docks, piers and marinas, chemical and petroleum processing plants, and aviation facilities.
- Lighting of tunnels, bridges, stairs, wheelchair elevator lifts for American with Disabilities Act (ADA) compliance, and ramps that are not parking garage ramps.
- In theme parks: outdoor lighting only for themes and special effects.
- Lighting for outdoor theatrical and other outdoor live performances, provided that these lighting systems are additions to area lighting systems and are controlled by a multi-scene or theatrical cross-fade control station accessible only to authorized operators.
- Outdoor lighting systems for qualified historical buildings, as defined in the California Historical Building Code (Title 24, Part 8), if they consist solely of historical lighting components or replicas of historical lighting components. If lighting systems for qualified historical buildings contain some historical lighting components or replicas of historical components, combined with other lighting components, only those historical or historical replica components are exempt. All other outdoor lighting systems for qualified historical buildings shall not be exempted.
APPENDIX A4-10 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE
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APPENDIX A4 — RESIDENTIAL VOLUNTARY MEASURES
SECTION A4.204 — REQUIREMENTS FOR ALTERATIONS TO EXISTING BUILDINGS
A4.204.1 Energy efficiency. Alterations to existing residential buildings shall comply with Sections A4.204.1.1 and A4.204.1.2.
A4.204.1.1 Altered space-conditioning system serving existing single-family dwelling units – mechanical cooling. When a space-conditioning system serving an existing single-family dwelling unit is altered in Climate Zones 1 through 14 and 16 by installation or replacement of an air conditioner, the altered system shall comply with either a or b below in addition to the requirements for installation specified by Title 24, Part 6, Sections 150.2(b)1E and 150.2(b)1F: a. A heat pump shall be the primary heating source and sized according to the system selection requirements specified by Title 24, Part 6 of Section 150.0(h)5. Supplemental heating may be provided by an existing gas furnace or existing electric resistance heating; or b. An air conditioner shall meet the following requirements: i. R-8 duct insulation for ducts located in unconditioned space; and ii. The duct system measured air leakage shall be equal to or less than 5 percent of the system air handler airflow as confirmed through field verification and diagnostic testing, per the requirements in Title 24, Part 6, Reference Residential Appendix Section RA3.1.4.3.1; and iii. Demonstrate, in every control mode, airflow greater than or equal to 400 CFM per ton of nominal cooling capacity through the return grilles, and an air-handling unit fan efficacy less than or equal to 0.35 W/CFM. The airflow rate and fan efficacy requirements in this section shall be confirmed through field verification and diagnostic testing, following the procedures outlined in Title 24, Part 6, Reference Residential Appendix RA3.3; and iv.
CRC § 0.099 Medium relevance — show source text
3(1)—continued Col2 Col3 Col4 NOMINAL MATE-
RIAL THICKNESS
(inches)DESCRIPTIONa, b OF FASTENER AND LENGTH
(inches)SPACINGc OF FASTENERS SPACINGc OF FASTENERS NOMINAL MATE-
RIAL THICKNESS
(inches)DESCRIPTIONa, b OF FASTENER AND LENGTH
(inches)Edges
(inches)Body of paneld
(inches)Floor underlayment; plywood-hardboard-particleboardf-fiber-cementh Floor underlayment; plywood-hardboard-particleboardf-fiber-cementh Floor underlayment; plywood-hardboard-particleboardf-fiber-cementh Floor underlayment; plywood-hardboard-particleboardf-fiber-cementh Fiber-cement Fiber-cement Fiber-cement Fiber-cement 1/4 11/4 long × 0.099″ corrosion-resistant, ring shank nails (finished flooring other than tile) 3 6 1/4 Staple 18 ga.7/8 long,1/4 crown (finished flooring other than tile) 3 6 1/4 11/4 long × .121 shank × .375 head diameter corrosion-resistant
(galvanized or stainless steel) roofing nails (for tile finish)8 8 1/4 11/4 long, No. 8 × .375 head diameter, ribbed wafer-head screws (for tile finish) 8 8 Plywood Plywood Plywood Plywood 1/4 and5/16 11/4 ring or screw shank nail-minimum 121/2 ga. (0.099″) shank diameter 3 6 1/4 and5/16 Staple 18 ga.,7/8, 3/16 crown width 2 5 11/32, 3/8, 15/32 and1/2 11/4 ring or screw shank nail-minimum 121/2 ga. (0.099″) shank diameter 6 8e 19/32, 5/8, 23/32 and3/4 11/2 ring or screw shank nail-minimum 121/2 ga. (0.099″) shank diameter 6 8 19/32, 5/8, 23/32 and3/4 Staple 16 ga. CRC § 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 degrees110 500 1,000 2,500 5,000 Backlight Medium (BM)
30 to < 60 degrees220 1,000 2,500 5,000 8,500 Backlight Low (BL)
0 to < 30 degrees110 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 degrees0 10 50 500 1,000 Uplight Low (UL)
90 to < 100 degrees0 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,CRC § 5.503 Medium relevance — show source text
SECTION 5.503—FIREPLACES
5.503.1 Fireplaces. Install only a direct-vent sealed-combustion gas or sealed wood-burning fireplace, or a sealed woodstove or pellet stove, and refer to residential requirements in the California Energy Code, Title 24, Part 6, Subchapter 7, Section 150. Woodstoves, pellet stoves and fireplaces shall comply with applicable local ordinances.
5.503.1.1 Woodstoves. Woodstove and pellet stoves shall comply with US EPA New Source Performance Standards (NSPS) emission limits as applicable, and shall have a permanent label indicating they are certified to meet the emission limits.
SECTION 5.504—POLLUTANT CONTROL
5.504.1 Temporary ventilation. The permanent HVAC system shall only be used during construction if necessary to condition the building or areas of addition or alteration within the required temperature range for material and equipment installation. If the HVAC system is used during construction, use return air filters with a Minimum Efficiency Reporting Value (MERV) of 13, based on ASHRAE 52.2. Replace all filters immediately prior to occupancy, or, if the building is occupied during alteration, at the conclusion of construction.
5.504.2 Reserved.
5.504.3 Covering of duct openings and protection of mechanical equipment during construction. At the time of rough installation and during storage on the construction site until final startup of the heating, cooling and ventilating equipment, all duct and
2025 CALIFORNIA GREEN BUILDING STANDARDS CODE 5-31
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NONRESIDENTIAL MANDATORY MEASURES
other related air distribution component openings shall be covered with tape, plastic, sheet metal or other methods acceptable to the enforcing agency to reduce the amount of dust, water and debris which may enter the system.
5.504.4 Finish material pollutant control. Finish materials shall comply with Sections 5.504.4.1 through 5.504.4.6.
5.504.4.1 Adhesives, sealants and caulks. Adhesives, sealants and caulks used on the project shall meet the requirements of the following standards:
- Adhesives, adhesive bonding primers, adhesive primers, sealants, sealant primers and caulks shall comply with local or regional air pollution control or air quality management district rules where applicable, or SCAQMD Rule 1168 VOC limits, as shown in Tables 5.504.4.1 and 5.504.4.2. Such products also shall comply with the Rule 1168 prohibition on the use of certain toxic compounds (chloroform, ethylene dichloride, methylene chloride, perchloroethylene and trichloroethylene), except for aerosol products as specified in subsection 2, below.
- Aerosol adhesives, and smaller unit sizes of adhesives, and sealant or caulking compounds (in units of product, less packaging, which do not weigh more than one pound and do not consist of more than 16 fluid ounces) shall comply with statewide VOC standards and other requirements, including prohibitions on use of certain toxic compounds, of Califor- nia Code of Regulations, Title 17, commencing with Section 94507.
|TABLE 5.504.4.1—ADHESIVE VOC LIMIT1,2—Less Water and Less Exempt Compounds in Grams Per
CRC § 204.1 Medium relevance — show source text
** Buildings complying with the second level of advanced energy efficiency shall have an Energy Budget that is no greater than indicated below, depending on building type and the type of energy systems included in the building project. If the newly constructed building or addition does not include indoor lighting or mechanical systems, then no additional performance requirements above Title 24, Part 6 are required.
- For nonresidential building projects that include indoor lighting or mechanical systems, but not both: No greater than 90 percent of the Title 24, Part 6, Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
- For nonresidential building projects that include indoor lighting and mechanical systems: No greater than 85 percent of the Title 24, Part 6, Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
- For high-rise residential and hotel/motel building projects: No greater than 95 percent of the Title 24, Part 6, Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
Note: For Energy Budget calculations, high-rise residential and hotel/motel buildings are considered nonresidential buildings.
SECTION A5.204—MANDATORY REQUIREMENTS FOR ALTERATIONS TO EXISTING BUILDINGS
A5.204.1 Energy efficiency . Alterations to existing nonresidential buildings shall comply with Section A5.204.1.1.
A5.204.1.1 Altered pool and/or spa heating for existing nonresidential buildings . Alteration of existing nonresidential pool and/or spa heating system shall meet the following.
Heating source sizing. Heating systems or equipment for pools or spas shall meet one of the sizing requirements of Items 1 through 5 below:
- Solar pool heating system with a solar collector surface area that is equivalent to 65 percent or greater of the surface areas of the pool or spa or a combination of both respectively; or
- A heat pump pool heater as the primary heating system that meets the sizing requirements of Reference Joint Appendix JA16.3. The control for the heat pump pool heater shall meet the requirements specified in Section 110.4(d). The supplementary heater can be of any energy source; or
- A heating system that derives at least 60 percent of the annual heating energy from on-site renewable energy or on-site recovered energy; or
- A combination of a solar pool heating system and heat pump pool heater without any additional supplementary heater;
or
- A pool heating system determined by the Energy Commission Executive Director to use no more energy than the systems specified in Item 1, 2, 3, or 4 above.
Exception 1 to A5.204.1.1: Portable electric spas compliant with 20 CCR, Section 1605.3(g)(7) of the Appliance Efficiency Regulations.
Exception 2 to A5.204.1.1: A pool or spa that is heated solely by a solar pool heating system without any supplementary heater.
Exception 3 to A5.204.1.1: An existing building with inadequate Solar Access Roof Area (SARA) as specified in Section 140.10(a) for a solar pool heating system to be installed.
Exception 4 to A5.204.1.1: Heating systems which are used exclusively for permanent spa applications in existing buildings with gas availability.
SECTION A5.211—RESERVED
SECTION A5.212—ELEVATORS, ESCALATORS AND OTHER EQUIPMENT
CRC § 8-32 Medium relevance — show source text
(g) Grounding. Cabinets, metalware enclosures and noncurrent carrying metal parts shall be grounded as required by the Califor- nia Electrical Code . Equipment grounded by a multiple-conductor cord shall have a fixed contacting member in the attachment plug for connection of the grounding conductor. The grounding conductor shall be green-identified and shall not be used as a circuit conductor.
(h) Operating mechanisms.
- Parts and motors shall be suitable for the particular applications and shall be of sufficient mechanical strength and capacity to withstand the stresses to which they will be subjected in operation without introducing any hazard.
- Cams, signaling wheels and similar parts shall be fastened to prevent loosening or independent turning. Adjustable parts and adjusting screws shall have provisions to prevent loosening under conditions of use.
- Electromagnetic devices shall be designed to provide positive electrical and mechanical performance under all conditions of use.
(i) Current-carrying parts.
- Current-carrying parts shall be of nonferrous metal recognized as suitable and of sufficient mechanical strength for the particular application.
- Except for grounded signaling wheels, bearings, hinges, etc., shall not be used for carrying current between interrelated fixed and moving parts.
(j) Supply connections. Control units and combination signaling systems shall be provided with wiring terminals for the connection of conductors of at least the size required by the California Electrical Code, for the electrical rating of the equipment.
(k) Terminal connections.
- Wiring terminals shall ensure thorough connections under hard usage. Terminals shall be a suitable pressure wire connector, firmly bolted or held by a screw, except that for No. 8 AWG and smaller wires, a wire binding screw having upturned lugs or the equivalent may be used. Alternate: Binding screws without upturned lugs may be recognized when conductors are fitted with mechanically and electrical secure ring connectors.
- Wire-binding screws not less than 8-32 may be used at terminal strips, except that a 6-32 screw may be used for No. 14 AWG and smaller wires. Terminal plates shall be not less than 0.050 inch (1 mm) in thickness to provide not less than two full threads in the metal. Terminal plates of less thickness may be recognized when the resistance to stripping of the threads is equal to or greater than two full threads in 0.050-inch-thick (1 mm) terminal plates.
(l) Raceways and power-supply cord.
- Control units shall have provisions for connection of armored cable or conduit. Combination signaling systems may be provided with a flexible cord and attachment cap. The power-supply cord serving the fire alarm signal generator or tone oscillator shall be Type SJ or equivalent. Strain relief shall be provided so that mechanical stress on a flexible cord will not be transmitted to terminals, splices or interior wiring. Power-supply for the signal generator or tone oscillator provided by a cord shall have an attachment cap with a device to prevent its easy removal from the receptacle.
- Power-supply for clock, communication or program systems shall not be supplied from the fire alarm control unit.
(m) Internal wiring.
- Internal wiring of a control unit or combination signaling system shall consist of suitably insulated conductors for the voltage and temperature attained, and of adequate current-carrying capacity for the service.
- All conductors in an enclosure or raceway shall be insulated for the maximum voltage of any conductor in the enclosure or
CRC § 44-18 Medium relevance — show source text
R303.4
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REFERENCED STANDARDS
276—23: Standard Method of Fire Test for Determining the Heat Release Rate of Roofing Assemblies with Combustible Above- Deck Roofing Components
R906.1
286— 24 : Standard Methods of Fire Tests for Evaluating Contribution of Wall and Ceiling Interior Finish to Room Fire Growth
R302.9.4, R303.6
501—22: Standard on Manufactured Housing
R202
720—15: Standard for the Installation of Carbon Monoxide (CO) Detection and Warning Equipment
R311.7.1, R311.7.2
PCA Portland Cement Association 5420 Old Orchard Road Skokie, IL 60077
100—17: Prescriptive Design of Exterior Concrete Walls for One- and Two-family Dwellings (Pub. No. PCA 100.3)
R301.2.2.5, R404.1.3, R404.1.3.2.1, R404.1.3.2.2, R404.1.3.4, R404.1.4.2, R608.1, R608.2, R608.5.1, R608.9.2, R608.9.3
PTI Post-Tensioning Institute 38800 Country Club Drive Farmington Hills, MI 48331
PTIDC10.5—19: Standard Requirements for Design and Analysis of Shallow Concrete Foundations on Expansive and Stable Soils
R506.2
SBCA Structural Building Components Association 6300 Enterprise Lane Madison, WI 53719
BCSI—2018: Building Component Safety Information—Guide to Good Practice for Handling, Installing, Restraining & Bracing of Metal Plate Connected Wood Trusses
R502.12.2, R802.10.3
CFS-BCSI—(updated June 2016): Cold-formed Steel Building Component Safety Information (CFSBCSI)—Guide to Good Practice for Handling, Installing & Bracing of Cold-formed Steel Trusses
R505.1.3, R804.3.6
SFM State of California Department of Forestry and Fire Protection, Office of the State Fire Marshal, P.O. Box 944246, Sacramento, CA
944246-2460
SFM—12-3: Releasing Systems for Security Bars in Dwellings
SFM 12-7A-1: Exterior Wall Siding and Sheathing
SFM 12-7A-2: Exterior Window
SFM 12-7A-3: Horizontal Protection Underside
SFM 12-7A-4: Decking
SFM 12-7A-4A: Decking Alternate Method A
(The Office of the State Fire Marshal standards referred to above are found in the California Code of Regulations, Title 24, Part 12.)
TMS The Masonry Society 105 South Sunset Street, Suite Q Longmont, CO 80501
402—2022: Building Code Requirements for Masonry Structures
CRC § 201.1 Medium relevance — show source text
SECTION A4.201—GENERAL
A4.201.1 Scope. For the purposes of mandatory energy efficiency standards in the California Building Standards Code (Title 24), the California Energy Commission will continue to adopt mandatory standards in the California Energy Code (Title 24, Part 6). It is the intent of these voluntary provisions to encourage local jurisdictions through codification to achieve exemplary performance in the area of building energy efficiency. Local jurisdictions adopting these voluntary provisions as mandatory local energy efficiency standards shall submit the required application and receive the required approval of the California Energy Commission in compliance with Title 24, Part 1, Section 10-106 prior to enforcement. Once the required filing has been verified and finding has been made by the Energy Commission, local jurisdictions shall file an ordinance expressly marking the local modification along with findings and receive the required acceptance from the California Building Standards Commission in compliance with Section 101.7 of this code, prior to enforcement. (Title 24, Part 1, Section 10-106 is available at https://www.energy.ca.gov/programs-and-topics/programs/build- ing-energy-efficiency-standards/2025-building-energy-efficiency
SECTION A4.202—DEFINITIONS
A4.202.1 Definitions. The following terms are defined in Chapter 2.
ENERGY BUDGET.
LONG-TERM SYSTEM COST (LSC).
RECOVERED ENERGY, ON-SITE.
SOLAR POOL HEATING SYSTEM.
SECTION A4.203—PERFORMANCE APPROACH FOR NEWLY CONSTRUCTED BUILDINGS
A4.203.1 Energy efficiency. Newly constructed low-rise residential buildings shall comply with Sections A4.203.1.1 through A4.203.1.4.
A4.203.1.1 Long-term system cost (LSC). LSC rating for the building’s Proposed Design shall be computed by Compliance Software certified by the Energy Commission as specified in Title 24, Part 6, Section 100.1 and 150.1(b), and shall reduce the LSC required in the Compliance Software for minimum performance-based compliance with the California Energy Code by the compliance margin specified in Table A4.203.1.1. The rating shall be included in the Certificate of Compliance documentation.
TABLE A4.203.1.1—RECOMMENDED LSC MARGINS BY CLIMATE ZONES Col2 CALIFORNIA ENERGY CODE CLIMATE ZONE TOTAL LSC COMPLIANCE MARGIN 1 2.70 2 1.62 3 1.10 4 1.11 5 1.01 6 0.24 7 0.24 8 0.21 9 0.20 10 0.18 11 1.11 12 1.05 13 0.96 14 1.21 15 0.59 16 1.68 Note: Community shared options complying with Title 24, Part 1, Section 10-115 may be used to achieve LSC targets. Note: Community shared options complying with Title 24, Part 1, Section 10-115 may be used to achieve LSC targets. 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A4-9
CRC § 10-109 Medium relevance — show source text
COMPLIANCE SOFTWARE is software that has been approved pursuant to Section 10-109 of Part 1 of Title 24 of the California Code of Regulations, to demonstrate compliance with the performance approach of Part 6.
COMPRESSED AIR SYSTEM is a system of at least one compressor providing compressed air at 40 psig or higher.
COMPUTER ROOM is a room within a building whose primary function is to house electronic equipment and that has a design information technology equipment (ITE) equipment power density exceeding 20 watts/ft [2] (215 watts/m [2] ) of conditioned floor area.
CONDENSER is a refrigeration component that condenses refrigerant vapor by rejecting heat to air mechanically circulated over its heat transfer surface.
CONDENSER, ADIABATIC is a condenser that has the ability to use two heat transfer processes in series as accomplished by a single factory-made unit. The first heat transfer process is the precooling of the entering air by lowering the entering air drybulb temperature. The second heat transfer process is forced-air circulation cooling over the heat transfer surface of the condenser.
DRY MODE is an operating condition of an adiabatic condenser wherein the only means of heat transfer is accomplished through forced-air circulation over the heat transfer surface of the condenser without any precooling of the entering air.
PRECOOL MODE is an operating condition of an adiabatic condenser wherein the entering air is precooled.
CONDENSER SPECIFIC EFFICIENCY is the full load condenser Total Heat of Rejection (THR) capacity at standardized conditions divided by the fan input electric power (including but not limited to spray pump electric input power for evaporative condensers) at 100 percent rated fan speed.
CONDITIONED FLOOR AREA (CFA) is the floor area (in square feet) of enclosed conditioned space on all floors of a building, as measured at the floor level of the exterior surfaces of exterior walls enclosing the conditioned space.
CONDITIONED GREENHOUSE is a greenhouse that is provided with wood heating, mechanical heating that has a capacity exceeding 10 Btu/hr-ft2, or mechanical cooling that has a capacity exceeding 5 Btu/hr-ft2.
CONDITIONED SPACE is an enclosed space within a building that is directly conditioned or indirectly conditioned.
CONDITIONED SPACE, DIRECTLY is an enclosed space that is provided with wood heating, mechanical heating that has a capacity exceeding 10 Btu/hr-ft [2] ) or mechanical cooling that has a capacity exceeding 5 Btu/hr-ft [2] . Directly conditioned space does not include process space. (See “process space.”)
CONDITIONED SPACE, INDIRECTLY is enclosed space that (1) is not directly conditioned space; and (2) either (a) has a thermal transmittance area product (UA) to directly conditioned space exceeding that to the outdoors or to unconditioned space and does not have fixed vents or openings to the outdoors or to unconditioned space, or (b) is a space through which air from directly conditioned spaces is transferred at a rate exceeding three air changes per hour.
CONDITIONED VOLUME is the total volume (in cubic feet) of the conditioned space within a building.
CONTINUOUS INSULATION (c.i.) is insulation that is continuous across all assemblies that separate conditioned from unconditioned space. It is installed on the exterior or interior or is integral to any opaque surface of the building envelope and has no thermal bridges other than fasteners and necessary service openings.
CRC § 203.1.1.3 Medium relevance — show source text
A5.203.1.1.3 Warehouse dock seal doors. Exterior loading dock doors that are adjacent to conditioned or indirectly conditioned spaces shall have dock seals or dock shelters installed at the time of permitting. This requirement shall apply to newly constructed buildings and to loading dock doors added to existing buildings.
A5.203.1.1.4 Daylight Design Power Adjustments Factors (PAFs). Daylighting devices shall be installed as specified in Title 24, Part 6, Section 140.3(d).
A5.203.1.1.5 Exhaust air heat recovery. Heat recovery requirements based on ASHRAE 90.1, Section 6.5.6.1 are adapted and modified for California climate zones as described below.
- Systems with minimum design outdoor air fraction of 80 percent or greater and supply air flow of 200 cfm or greater in climate zones 2, 9, 10, 11, 12, 13, 14, 15 shall have a heat recovery system.
- Heat recovery systems required by this section shall result in a net sensible energy recovery ratio of at least 60 percent for both heating and cooling as tested using AHRI 1060-2014 or 1061-2014 and certified by AHRI. A 60 percent sensible energy recovery ratio shall mean a change in the dry-bulb of the outdoor air supply equal to 60 percent of the difference between the outdoor air and exhaust air dry-bulb at design conditions. Provisions shall be made to bypass or control the energy recovery system to permit air economizer operation as required by Title 24, Part 6, Section 140.4(e), Economizers.
Exceptions:
Systems serving spaces that are not cooled and that are heated to less than 60°F.
Where more than 60 percent of the outdoor air heating energy is provided from site-recovered energy.
Where the sum of the airflow rates exhausted and relieved within 20 feet of each other is less than 75 percent of the design outdoor airflow rate, excluding exhaust air that is:
Used for another energy recovery system;
Not allowed by ASHRAE Standard 170 for use in energy recovery systems with leakage potential; or
Of Class 4 as defined in ASHRAE Standard 62.1.
Systems expected to operate less than 20 hours per week.
A5.203.1.2 Performance standard. Comply with one of the advanced efficiency levels indicated below.
A5.203.1.2.1 Tier 1. Buildings complying with the first level of advanced energy efficiency shall have an Energy Budget that is no greater than indicated below, depending on building type and the type of energy systems included in the building project. If the newly constructed building or addition does not include indoor lighting or mechanical systems, then no additional performance requirements above Title 24, Part 6 are required.
- For nonresidential building projects that include indoor lighting or mechanical systems, but not both: No greater than 95 percent of the Title 24, Part 6, Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
- For nonresidential building projects that include indoor lighting and mechanical systems: No greater than 90 percent of the Title 24, Part 6 Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
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CRC § 62.1. Medium relevance — show source text
Of Class 4 as defined in ASHRAE Standard 62.1.
Systems expected to operate less than 20 hours per week.
A5.203.1.2 Performance standard. Comply with one of the advanced efficiency levels indicated below.
A5.203.1.2.1 Tier 1. Buildings complying with the first level of advanced energy efficiency shall have an Energy Budget that is no greater than indicated below, depending on building type and the type of energy systems included in the building project. If the newly constructed building or addition does not include indoor lighting or mechanical systems, then no additional performance requirements above Title 24, Part 6 are required.
- For nonresidential building projects that include indoor lighting or mechanical systems, but not both: No greater than 95 percent of the Title 24, Part 6, Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
- For nonresidential building projects that include indoor lighting and mechanical systems: No greater than 90 percent of the Title 24, Part 6 Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
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APPENDIX A5 — NONRESIDENTIAL VOLUNTARY MEASURES
- For high-rise residential and hotel/motel building projects: No greater than 95 percent of the Title 24, Part 6, Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
A5.203.1.2.2 Tier 2. Buildings complying with the second level of advanced energy efficiency shall have an Energy Budget that is no greater than indicated below, depending on building type and the type of energy systems included in the building project. If the newly constructed building or addition does not include indoor lighting or mechanical systems, then no additional performance requirements above Title 24, Part 6 are required.
- For nonresidential building projects that include indoor lighting or mechanical systems, but not both: No greater than 90 percent of the Title 24, Part 6, Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
- For nonresidential building projects that include indoor lighting and mechanical systems: No greater than 85 percent of the Title 24, Part 6, Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
- For high-rise residential and hotel/motel building projects: No greater than 95 percent of the Title 24, Part 6, Energy Budget for the Standard Design Building as calculated by compliance software certified by the Energy Commission.
Note: For Energy Budget calculations, high-rise residential and hotel/motel buildings are considered nonresidential buildings.
SECTION A5.204—MANDATORY REQUIREMENTS FOR ALTERATIONS TO EXISTING BUILDINGS
A5.204.1 Energy efficiency . Alterations to existing nonresidential buildings shall comply with Section A5.204.1.1.
A5.204.1.1 Altered pool and/or spa heating for existing nonresidential buildings . Alteration of existing nonresidential pool and/or spa heating system shall meet the following.
Heating source sizing. Heating systems or equipment for pools or spas shall meet one of the sizing requirements of Items 1 through 5 below: 1.
CRC § 10-109 Medium relevance — show source text
(b) Performance approach. A building complies with the performance approach if the energy consumption calculated for the proposed design building is no greater than the energy budget calculated for the standard design building using Commission-certified compliance software as specified by Sections 10-109(c) and 10-116.
- Energy budget. The energy budget is expressed in terms of source energy and long-term system cost (LSC). A. Long-term system cost (LSC). The LSC energy budget is determined by applying the mandatory and prescriptive requirements of the standard design to the proposed design building and has two components, the Efficiency LSC and the Total LSC.
i. The Efficiency LSC energy is the sum of the LSC energy for space-conditioning, water heating, mechanical ventilation, and the self-utilization credit.
ii. The Total LSC energy is the sum of the Efficiency LSC energy and LSC energy from the photovoltaic system, battery energy storage systems (BESS), lighting, demand flexibility, and other plug loads. B. Source energy. The source energy budget is determined by applying the mandatory and prescriptive requirements of the standard design to the proposed design building. The source energy is the total annual source energy. Exception to Section 150.1(b)1. A community shared solar electric generation system, or other renewable electric generation system, or community shared BESS, which provides dedicated power, utility energy reduction credits, or payments for energy bill reductions to the permitted building and is approved by the Energy Commission as specified in Title 24, Part 1, Section 10-115, may offset part or all of the solar electric generation system and demand flexibility Energy Design Rating required to comply with the Standards, as calculated according to methods established by the Commission in the Residential ACM Reference Manual.
- 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.
CRC § 10-109 Medium relevance — show source text
- The standard design shall assume the same geometry and orientation as the proposed design.
- The “existing efficiency level” modeling rules, including situations where nameplate data are not available, are described in Sections 10-109(c) and 10-116. Exception 1 to Section 150.2(b): Any dual- glazed greenhouse or/garden window installed as part of an alteration complies with the U -factor requirements in Section 150.1(c)3. Exception 2 to Section 150.2(b): Where the space in the attic or rafter area is not large enough to accommodate the required R -value, the entire space shall be filled with insulation, provided such installation does not violate Section 1203.2 of Title 24, Part 2.
(c) Whole building. Any addition or alteration may comply with the requirements of Title 24, Part 6 by meeting the requirements for the entire building.
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, 25910, and 25943, Public Resources Code .
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CALIFORNIA MECHANICAL CODE, CALIFORNIA CODE OF REGULATIONS, TITLE 24, PART 4, CHAPTER 6, DUCT SYSTEMS
CALIFORNIA MECHANICAL CODE, CALIFORNIA CODE OF REGULATIONS, TITLE 24, PART 4, CHAPTER 6, DUCT SYSTEMS
TABLE P4-A ADOPTION TABLE Col2 Col3 CODE SECTION AGENCY Adopt entire Chapter as amended (amended sections listed below)1 CEC 601.0 X 602.0 X 603.0 X 604.0 X 605.0 X 1. Adopted by reference for Occupancies A, B, E, F, H, M, R, S, and U; see Sections 110.8(d)3, 120.4 and 150.0(m). 1. Adopted by reference for Occupancies A, B, E, F, H, M, R, S, and U; see Sections 110.8(d)3, 120.4 and 150.0(m). 1. Adopted by reference for Occupancies A, B, E, F, H, M, R, S, and U; see Sections 110.8(d)3, 120.4 and 150.0(m). 2025 CALIFORNIA ENERGY CODE 197
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10 MULTIFAMILY BUILDINGS—MANDATORY REQUIREMENTS
SECTION 160.0—GENERAL
CRC § 1.1 Medium relevance — show source text
SECTION R313—CEILING HEIGHT
R313.1 Minimum height. Habitable space, hallways and portions of basements containing these spaces shall have a ceiling height of not less than 7 feet (2134 mm). Bathrooms, toilet rooms and laundry rooms shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).
Exceptions:
- For rooms with sloped ceilings, the required floor area of the room shall have a ceiling height of not less than 5 feet (1524 mm) and not less than 50 percent of the required floor area shall have a ceiling height of not less than 7 feet (2134 mm).
- The ceiling height above bathroom and toilet room fixtures shall be such that the fixture is capable of being used for its intended purpose. A shower or tub equipped with a showerhead shall have a ceiling height of not less than 6 feet 8 inches (2032 mm) above an area of not less than 30 inches (762 mm) by 30 inches (762 mm) at the showerhead.
- Beams, girders, ducts or other obstructions in basements containing habitable space shall be permitted to project to within 6 feet 4 inches (1931 mm) of the finished floor.
- Beams and girders spaced apart not less than 36 inches (914 mm) in clear finished width shall project not more than 78 inches (1981 mm) from the finished floor.
R313.1.1 Basements. Portions of basements that do not contain habitable space or hallways shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).
Exception: At beams, girders, ducts or other obstructions, the ceiling height shall be not less than 6 feet 4 inches (1931 mm) from the finished floor.
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BUILDING PLANNING
R313.1.2 Habitable attics and basements in existing buildings. Where a habitable attic or habitable space in a basement is created in an existing building, ceiling height shall not be less than 6 feet 8 inches (2032 mm). Bathrooms, toilet rooms and laundry rooms shall have a ceiling height of not less than 6 feet 4 inches (1930 mm).
Exceptions:
- For rooms with sloped ceilings, the required floor area of the room shall have a ceiling height of not less than 5 feet (1524 mm) and not less than 50 percent of the required floor area shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).
- At beams, girders, ducts or other obstructions, the ceiling height shall be not less than 6 feet 4 inches (1930 mm) from the finished floor.
SECTION R314—MEZZANINES
R314.1 General. Mezzanines shall comply with Sections R314.2 through R314.5.
Exception: Sleeping lofts in dwelling units and sleeping units shall be permitted to comply with Section R315, subject to the limitations in Section R315.2.
R314.2 Mezzanines. The clear height above and below mezzanine floor construction shall be not less than 7 feet (2134 mm).
CRC § 2.5 Medium relevance — show source text
iv. Attic ventilation shall comply with the California Residential Code, Title 24, Part 2.5, Section R806. Exception 1 to Section 150.2(b)1J: Dwelling units with at least R-38 existing insulation installed at the ceiling level. Exception 2 to Section 150.2(b)1J: Dwelling units where the alteration would directly cause the disturbance of asbestos.
Exception 3 to Section 150.2(b)1J: Dwelling units with knob and tube wiring located in the vented attic.
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on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
SINGLE-FAMILY RESIDENTIAL BUILDINGS—ADDITIONS AND ALTERATIONS TO EXISTING RESIDENTIAL BUILDINGS
Exception 4 to Section 150.2(b)1J: Where the accessible space in the attic is not large enough to accommodate the required R -value, the entire accessible space shall be filled with insulation provided such installation does not violate Section 806.3 of Title 24, Part 2.5. Exception 5 to Section 150.2(b)1J: Where the attic space above the altered dwelling unit is shared with other dwelling units and the requirements of Section 150.2(b)1J are not triggered for the other dwelling units. K. Lighting. The altered lighting system shall meet the lighting requirements of Section 150.0(k). The altered luminaires shall meet the luminaire efficacy requirements of Section 150.0(k). Where existing screw-base sockets are present in ceiling-recessed luminaires, removal of these sockets is not required provided that new JA8-compliant trim kits or lamps designed for use with recessed downlights or luminaires are installed. L. Mechanical ventilation for indoor air quality—entirely new or complete replacement ventilation systems. Entirely new or complete replacement ventilation systems shall comply with all applicable requirements in Section 150.0(o). An entirely new or complete replacement ventilation system includes a new ventilation fan component and an entirely new duct system. An entirely new or complete replacement duct system is constructed of at least 75 percent new duct material, and up to 25 percent may consist of reused parts from the dwelling unit's existing duct system, including but not limited to registers, grilles, boots, air filtration devices and duct material, if the reused parts are accessible and can be sealed to prevent leakage. M. Mechanical ventilation for indoor air quality—altered ventilation systems. Altered ventilation system components or newly installed ventilation equipment serving the alteration shall comply with Section 150.0(o) as applicable subject to the requirements specified in Subsections i and ii below. i. Whole-dwelling unit mechanical ventilation. a. Whole-dwelling unit airflow. If the whole-dwelling ventilation fan is altered or replaced, then one of the following Subsections 1 or 2 shall be used for compliance as applicable.
- Dwellings that were required by a previous building permit to comply with the whole-dwelling unit airflow requirements in Section 150.0(o) shall meet or exceed the whole-dwelling unit mechanical ventilation airflow specified in Section 150.0(o)1C, 150.0(o)1E or 150.0(o)1F as confirmed through field verification and diagnostic testing in accordance with the applicable procedures specified in Reference Residential Appendix RA3.7.
Frequently asked questions
What exactly is “compliance software” and who approves it?
Compliance software is the Energy Commission‑approved program used to run the Part 6 performance approach. The software must be certified/approved by the Energy Commission per the Part 6 approval process described around § 100.1 and related Part 1 rules.
When do I need field verification?
When your performance compliance depends on installed features that perform above Part 6 minimums (for example, a higher‑efficiency HVAC or verified duct tightness), § 150.1(b) requires field verification per the referenced Residential Appendices (RA) and documentation on the Certificate of Compliance.
Where do the Appendix A4 LSC margins get entered?
Appendix A4 instructs that the LSC rating for the Proposed Design be computed in Commission‑certified compliance software (per § 100.1) and that the software’s minimum LSC be reduced by the climate‑zone margin from Table A4.203.1.1; the LSC rating must be included on the Certificate of Compliance.
If Part IV of the Residential Code is “not adopted,” does that mean the home has no energy rules?
No. The CRC’s Part IV note points you to the California Energy Code (Title 24, Part 6) — that is the enforceable energy code for residential projects in California. See the CRC Part IV note and Part 6 §§ cited.
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