Title 24 · California Energy Code

Compliance paths and the standard‑design/proposed‑design concept

Title 24 Part 6 lets you comply by meeting prescriptive rules or by modeling a proposed design that does not exceed a standard‑design energy budget.

Last reviewed: July 6, 2026

Overview

This part of the California Energy Code (Title 24, Part 6) explains the two principal compliance paths—performance and prescriptive—and the standard‑design / proposed‑design comparison used when a project follows the performance approach. The performance path requires that the proposed design’s energy use not exceed the energy budget set by the standard design; those energy budgets are expressed in long‑term system cost (LSC) and source energy terms and are calculated with Commission‑certified compliance software (see §140.1 and §150.1).

Why this matters: the choice of path determines what you must submit with a permit application (certificates, software outputs, and field verification when higher‑than‑minimum performance is credited) and how alterations or additions are modeled. The code sets prescriptive rules in §140.2 (envelope, lighting, systems) and the performance rules in §140.1, and it specifies how existing vs. altered components are treated in additions/alterations (see §141.0 and the modeling rules for altered components).

In this section

Code references

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

  • § 10-109 High 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.

    1. 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.

    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.

  • § 62.1. Medium relevance — show source text
    1. Of Class 4 as defined in ASHRAE Standard 62.1.

    2. 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.

    1. 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.
    2. 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 A5NONRESIDENTIAL VOLUNTARY MEASURES

    1. 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.

    1. 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.
    2. 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.
    3. 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.

  • § 203.1.1 Medium 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.

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    APPENDIX A4RESIDENTIAL 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:

    1. Below roof deck insulation with a minimum R -value of 19; or,

    2. Continuous above deck insulation with a minimum R-8 and with an air space present between the roofing and the roof deck; or,

    3. 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.

  • § 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.

    1. 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.
    2. 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:

    1. Systems serving spaces that are not cooled and that are heated to less than 60°F.

    2. Where more than 60 percent of the outdoor air heating energy is provided from site-recovered energy.

    3. 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:

    4. Used for another energy recovery system;

    5. Not allowed by ASHRAE Standard 170 for use in energy recovery systems with leakage potential; or

    6. Of Class 4 as defined in ASHRAE Standard 62.1.

    7. 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.

    1. 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.
    2. 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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  • § 120.0 Medium relevance — show source text

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    ALL OCCUPANCIES—GENERAL PROVISIONS

    ii. Compliance approaches. In order to comply with Part 6, newly constructed nonresidential buildings and hotels/motels that are mechanically heated or mechanically cooled must meet the requirements of: a. Mandatory measures: The applicable provisions of Sections 120.0 through 130.5; and

    b. Either:

    (i) Performance approach: Section 140.1; or (ii) Prescriptive approach: Sections 140.2 through 140.10. C. Unconditioned nonresidential buildings and process space. Sections 110.9, 110.10, 120.6, 130.0 through 130.5, 140.3(c), 140.6, 140.7 and 140.8 apply to all newly constructed unconditioned buildings and for process spaces within the scope of Section 100.0(a). D. Single-family buildings. i. Sections applicable. Sections 150.0 through 150.1 apply to newly constructed single-family buildings. ii. Compliance approaches. In order to comply with Part 6, newly constructed single-family buildings must meet the requirements of: a. Mandatory measures: The applicable provisions of Sections 110.0 through 110.10 and 150.0; and

    b. Either:

    (i) Performance approach: Sections 150.1(a) and (b); or (ii) Prescriptive approach: Sections 150.1(a) and (c). Exception to Section 100.0(e)2Diib: Seasonally occupied agricultural housing limited by state or federal agency contract to occupancy not more than 180 days in any calendar year. E. Multifamily Buildings . i. Sections applicable. Sections 160.0 through 170.2 apply to newly constructed multifamily buildings. ii. Compliance approaches. In order to comply with Part 6, newly constructed multifamily buildings must meet the requirements of: a. Mandatory measures: The applicable provisions of Sections 110.0 through 110.10, and 160.0; and

    b. Either:

    (i) Performance approach: Section 170.1; or (ii) Prescriptive approach: Section 170.2(a) through (f).

    F. Covered processes.

    i. Sections applicable. Sections 110.2, 120.3, 120.6, 140.9, and 141.1 apply to covered processes. ii. Compliance approaches. In order to comply with Part 6, covered processes must meet the requirements of: a. The applicable mandatory measures in Sections 110.2, 120.3 and 120.6; and

    b. Either:

    (i) The performance approach requirements of Section 140.1; or (ii) The prescriptive approach requirements of Section 140.9. 3. New construction in existing buildings (additions, alterations and repairs). A. Nonresidential and hotel/motel buildings. Section 141.0 applies to new construction in existing nonresidential, high-rise residential and hotel/motel buildings. New construction in existing buildings includes additions, alterations and repairs. Section 141.0 specifies requirements that uniquely apply to additions, alterations or repairs to existing buildings, and specify which requirements in other sections also apply. For alterations that change the occupancy classification of the building, the requirements specified in Section 141.0 apply to the occupancy after the alterations. B. **Single-family buildings.

  • § 140.1 Medium relevance — show source text

    A. The Efficiency LSC energy is the sum of the LSC energy for space-conditioning, water heating, mechanical ventilation, and lighting. B. The Total LSC energy is the sum of the Efficiency LSC energy and LSC energy from the photovoltaic system, battery energy storage systems (BESS) and demand flexibility. 2. Source energy . The source energy budget is determined by applying the mandatory and prescriptive requirements of the standard design to the proposed design building.

    Exception to Section 140.1(a). A community shared solar electric generation system, or other renewable electric generation system, and/or community shared BESS, that 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 or BESS LSC energy required to comply with the standards, as calculated according to methods established by the Commission in the Nonresidential ACM Reference Manual.

    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 140.2—PRESCRIPTIVE APPROACH

    To comply using the prescriptive approach a building shall be designed with and shall have constructed and installed systems and components meeting the applicable requirements of Sections 140.3 through 140.10.

    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 140.3—PRESCRIPTIVE REQUIREMENTS FOR BUILDING ENVELOPES

    A building complies with this section by being designed with and constructed to meet all prescriptive requirements in Subsection (a) and the requirements of Subsection (c) and (d) where they apply.

    (a) Envelope component requirements.

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

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    NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES—PERFORMANCE AND PRESCRIPTIVE

    COMPLIANCE APPROACHES FOR ACHIEVING ENERGY EFFICIENCY

    A. Roofing products. Shall meet the requirements of Section 110.8 and the applicable requirements of Subsections i through ii: i. Nonresidential buildings: a. Low-sloped roofs in climate zones 1 through 16 shall have:

    1. A minimum aged solar reflectance of 0.63 and a minimum thermal emittance of 0.75; or
    2. A minimum solar reflectance index (SRI) of 75.
  • § 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.

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  • § 150.1 Medium relevance — show source text

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    8 SINGLE-FAMILY RESIDENTIAL BUILDINGS—PERFORMANCE

    AND PRESCRIPTIVE COMPLIANCE APPROACHES

    SECTION 150.1—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES FOR SINGLE-FAMILY RESIDENTIAL BUILDINGS

    (a) Basic requirements. Single-family residential buildings shall meet all of the following:

    1. The applicable requirements of Sections 110.0 through 110.10.
    2. The applicable requirements of Section 150.0 (mandatory features).
    3. Either the performance standards or the prescriptive standards set forth in this section for the climate zone in which the building is located. Climate zones are shown in Reference Joint Appendix JA2–Weather/Climate Data. Exception to Section 150.1(a)3: If a single contiguous subdivision or tract falls in more than one climate zone, all buildings in the subdivision or tract may be designed to meet the performance or prescriptive standards for the climate zone that contains 50 percent or more of the dwelling units. Note: The Commission periodically updates, publishes, and makes available to interested persons and local enforcement agencies precise descriptions of the climate zones, as specified in Reference Joint Appendix JA2–Weather/Climate Data.

    Note: The requirements of Sections 150.0(a) through 150.0(r) apply to newly constructed buildings and Sections 150.2(a) and 150.2(b) specifies changes to the requirements of Sections 150.1(a) through 150.1(c) that apply to additions or alterations.

    (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.

    1. 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.

  • § 160.0 Medium relevance — show source text
    1. Dwellings that were required by a previous building permit to install a vented kitchen range hood or other kitchen exhaust fan shall install a replacement fan that meets or exceeds the airflow required by the previous building permit, or 100 cfm, whichever is greater.
    2. Dwellings that were not required to have a kitchen local ventilation exhaust system according to the conditions in either Subsection 1 or 2 above shall not be required to comply with the requirements of Section 160.0(b)2Avi.

    c. Replacement ventilation fans. New or replacement local mechanical exhaust fans shall be rated for airflow and sound in accordance with the requirements of ASHRAE 62.2 Section 7.1 and Title 24, Part 6, Section 160.0(b)2Avif. Additionally, when compliance with a specified exhaust airflow rate is required, the replacement fan shall be rated at no less than the airflow rate required for compliance.

    (c) Performance approach. The altered component(s) and any newly installed equipment serving the alteration shall meet the applicable requirements of Subsections 1, 2 and 3 below. The energy budget for alterations is expressed in terms of long-term system cost (LSC) energy.

    1. The altered components shall meet the applicable requirements of Sections 110.0 through 110.9, 160.0, 160.1, 160.2(c) and (d), 160.3(a) through 160.3(b)5J, 160.3(b)6, 160.3(c), and 160.5. Entirely new or complete replacement mechanical ventilation systems as these terms are used in Section 180.2(b)5A shall comply with the requirements in Section 180.2(b)5A. Altered mechanical ventilation systems shall comply with the requirements of Sections 180.2(b)5B. Entirely new or complete replacement space-conditioning systems, and entirely new or complete replacement duct systems, as these terms are used in Sections 180.2(b)2Ai and 180.2(b)2Aiia, shall comply with the requirements of Sections 160.2(a)1 and 160.3(b)5L.

    2. The standard design for an altered component shall be the higher efficiency of existing conditions or the requirements of Section 180.2(b). For components not being altered, the standard design shall be based on the unaltered existing conditions such that the standard and proposed designs for these components are identical. When the third-party verification option is specified, all components proposed for alteration for which the additional credit is taken must be verified by a certified ECC-Rater.

    3. The proposed design shall be based on the actual values of the altered components. NOTES TO SECTION 180.2(c):

    4. If an existing component must be replaced with a new component, that component is considered an altered component for the purpose of determining the standard design altered component energy budget and must meet the requirements of Section 180.2(c)2.

    5. The standard design shall assume the same geometry and orientation as the proposed design.

    6. The “existing efficiency level” modeling rules, including situations where nameplate data is not available, are described in Section 10-109(c) and Section 10-116.

    EXCEPTION 1 to Section 180.2(c): Any dual-glazed greenhouse or garden window installed as part of an alteration complies with the U- factor requirements in Section 170.2.

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  • § 170.0 Medium relevance — show source text

    Exception to Section 170.0 (a)3: If a single development falls in more than one climate zone, all buildings in the subdivision or tract may be designed to meet the performance or prescriptive standards for the climate zone that contains 50 percent or more of the dwelling units.

    NOTE: The Commission periodically updates, publishes and makes available to interested persons and local enforcement agencies precise descriptions of the climate zones, as specified in Reference Joint Appendix JA2—Weather/Climate Data.

    NOTE: The requirements of Sections 170.1(a) through 170.2(e) apply to newly constructed buildings and Sections 180.1 and 180.2 specify changes to the requirements of Sections 170.1(a) through 170.2(e) that apply to additions or alterations.

    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 170.1—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 and 10-116 and the Alternative Calculation Method Reference Manual.

    (a) Energy budget. The energy budget is expressed in terms of long-term system cost (LSC) and source energy:

    1. 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.

    A. The Efficiency LSC energy is the sum of the LSC energy for space-conditioning, water heating, mechanical ventilation, lighting and the self-utilization credit. B. The Total LSC energy is the sum of the Efficiency LSC energy and LSC energy from the photovoltaic system, battery energy storage systems (BESS), and demand flexibility. 2. Source energy. The source energy budget is determined by applying the mandatory and prescriptive requirements of the standard design, except with a consumer gas or propane water heater, to the proposed design building.

    Exception to Section 170.1(a): A community shared solar electric generation system, or other renewable electric generation system, and/or community shared BESS, that 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 or BESS LSC energy required to comply with the standards, as calculated according to methods established by the Commission in the Nonresidential ACM Reference Manual.

    (b) Compliance demonstration requirements for performance standards.

    1. 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 that demonstrates, using an approved calculation method, that the building has been designed so that its source energy and LSC energy consumption do not exceed the standard design energy budgets for the applicable climate zone.
    2. Field verification of individual dwelling unit systems.
  • § 12-11 Medium relevance — show source text

    DETECTABLE WARNING PRODUCTS

    Sections 12-11A.203 and 12-11B.203. Must comply with the California Code of Regulations, Title 24.

    DIRECTIONAL SURFACES

    Sections 12-11A.204 and 12-11B.204. Must comply with the California Code of Regulations, Title 24.

    INDEPENDENT ENTITY

    Sections 12-11A.205 and 12-11B.205. Evaluation by an independent entity to confirm the prescriptive and performance standard of detectable warning products or direction surfaces installed after January 1, 2001. An independent entity is a not-for-profit product safety testing and certification organization, dedicated to testing for public safety. An independent entity would operate for the testing, certification and quality assessment of products, systems and services.

    TWO-YEAR APPROVAL

    Sections 12-11A.206 and 12-11B.206. Detectable warning products and directional surfaces are to be recertified every two years without exception or waiver.

    FEE

    Sections 12-11A.207 and 12-11B.207. The Division of the State Architect-Access Compliance may impose a fee on manufacturers of the specified products, to cover the cost of detectable warning products and directional surfaces.

    DISABILITY ACCESS ACCOUNT

    Sections 12-11A.208 and 12-11B.208. The fees received from manufacturers will be placed in the Disability Access Account.

    DETECTABLE WARNING PRODUCTS AND DIRECTIONAL SURFACES

    Sections 12-11A.209 and 12-11B.209. Detectable Warning Products and Directional Surfaces must ensure consistency and uniformity: (a) Shape, (b) Color fastness,

    (c) Conformation, (d) Sound-on-cane acoustic quality, (e) Resilience, and (f) Attachment will not degrade significantly for at least five years.

    SIGNIFICANT DEGRADATION

    Sections 12-11A.210 and 12-11B.210. Significant degradation means that the product maintains at least 90 percent of its approved design characteristics.

    SELECTION OF INDEPENDENT ENTITY

    Sections 12-11A.211 and 12-11B.211. The independent entity selected by the Division of the State Architect-Access Compliance shall be recognized as having appropriate expertise in determining whether products comply with the California Code of Regulations, Title 24.

    Authority: Government Code Sections 4450, 4460 and Health & Safety Code Section 18949.1.

    Reference: Government Code Section 4460.

    2025 CALIFORNIA REFERENCED STANDARDS CODE 85

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    86 2025 CALIFORNIA REFERENCED STANDARDS CODE

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    2025 CALIFORNIA REFERENCED STANDARDS CODE 87

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    12-13 STANDARDS FOR INSULATING MATERIAL

    (See Part 6, Title 24, CCR)

    DEPARTMENT OF CONSUMER AFFAIRS

    Bureau of Household Goods and Services

  • § 141.0 Medium relevance — show source text

    ADDITIONS, ALTERATIONS AND REPAIRS

    SECTION 141.0—ADDITIONS, ALTERATIONS AND REPAIRS TO EXISTING NONRESIDENTIAL AND HOTEL/ MOTEL BUILDINGS, TO EXISTING OUTDOOR LIGHTING, AND TO INTERNALLY AND EXTERNALLY ILLUMINATED SIGNS

    Additions, alterations, and repairs to existing nonresidential and hotel/motel buildings, existing outdoor lighting for these occupancies, and internally and externally illuminated signs, shall meet the requirements specified in Sections 100.0 through 110.12, and 120.0 through 130.5 that are applicable to the building project, and either the performance compliance approach (energy budgets) in Section 141.0(a)2 (for additions) or 141.0(b) 3 (for alterations), or the prescriptive compliance approach in Section 141.0(a)1 (for additions) or 141.0(b)2 (for alterations), for the Climate Zone in which the building is located. Climate zones are shown in Figure 100.1-A.

    Covered process requirements for additions, alterations and repairs to existing nonresidential and hotel/motel buildings are specified in Section 141.1.

    Exception to Section 141.0: Alterations to healthcare facilities are not required to comply with this Section.

    NOTES:

    1. For alterations that change the occupancy classification of the building, the requirements specified in Section 141.0(b) apply to the occupancy after the alterations.
    2. Relocation or moving of a relocatable public school building is not, by itself, considered an alteration for the purposes of Title 24, Part 6.

    (a) Additions. Additions shall meet either Item 1 or 2 below.

    1. Prescriptive approach. The envelope and lighting of the addition, any newly installed space-conditioning system, electrical power distribution system, or water-heating system; any addition to an outdoor lighting system; and any new sign installed in conjunction with an indoor or outdoor addition shall meet the applicable requirements of Sections 110.0 through 120.7, 120.9 through 130.5 and 140.2 through 140.9.
    2. Performance approach. A. The envelope and indoor lighting in the conditioned space of the addition, and any newly installed space-conditioning system, electrical power distribution system, or water-heating system, shall meet the applicable requirements of Sections 110.0 through 120.7, 120.9 through 130.5; and

    B. Either:

    i. The addition alone shall comply with Section 140.1; or ii. Existing plus addition plus alteration. The standard design for existing plus addition, plus alteration energy use is the combination of the existing building’s unaltered components to remain, existing building altered components that are the more efficient, in LSC, of either the existing conditions, or the requirements of Section 141.0(b)2, plus the proposed addition’s energy use meeting the requirements of Section 140.1. The proposed design energy use is the combination of the existing building’s unaltered components to remain and the altered component’s energy features, plus the proposed energy features of the addition.

    Exception 1 to Section 141.0(a): When heating, cooling or service water heating to an addition are provided by expanding existing systems, the existing systems and equipment need not comply with Sections 110.0 through 120.9 or Sections 140.4 through 140.5.

Frequently asked questions

What are the two main compliance paths under Title 24, Part 6?

You can use the prescriptive approach (meet the specific component and system requirements in §140.2 and related subsections) or the performance approach (demonstrate the proposed design’s energy use is no greater than the standard design energy budget under §140.1).

What does "standard design" vs "proposed design" mean?

The standard design is a modeled baseline that applies the code’s mandatory and prescriptive features to the project geometry; the proposed design is your actual project. Compliance is shown by comparing the proposed design to the standard design energy budgets (expressed in LSC and source energy) in the approved compliance software.

How are additions and alterations treated under the standard/proposed concept?

For additions and alterations the code specifies how to define the standard design (often the higher efficiency of existing conditions or code requirements) and the proposed design (actual altered values); special rules and verification options (including third‑party verification) appear in §141.0 and related alteration sections.

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