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Earlier editions: 20222019

Appendix A4

A4.203 Performance Approach for Newly Constructed Buildings — 2025 California Green Building Standards Code

California Green Building Standards Code (Title 24, Part 11) · 2025 edition · updated 2026-10-19 · California

CBSC: official editions, supplements and errata

Cite as: 2025 California Green Building Standards Code (Title 24, Part 11) § A4.203 · Effective January 1, 2026 · Official source: Building Standards Commission

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

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.

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.

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.

A4.203.1.3 Consultation with local electric service provider. Local jurisdictions considering adoption of reduced LSC targets based on using solar photovoltaic (PV) systems larger than required by the California Energy Code shall consult with the local electric service provider to ensure that PV system sizing required to comply with the LSC targets will be acceptable to the local electric service provider. The local jurisdiction shall not require onsite PV systems that are larger than the local electric service provider will allow to be interconnected.

A4.203.1.4 Outdoor luminaires. Outdoor luminaires installed for new multifamily buildings, hotels, and motels shall meet the following requirements.

A4.203.1.4.1 Outdoor pole-mounted and arm-mounted luminaires shall be installed with tilting not greater than 10 degrees, or the outdoor luminaires shall be installed with arm-mount or tenon-mount capable of tilting less than or within 10 degrees.

Exceptions to Section A4.203.1.4:

  1. Lighting for one- and two-family dwellings and townhouses with attached private garages.
  2. Lighting for building facades, public monuments, public art, statues and vertical surfaces of bridges.
  3. Lighting not permitted by a health or life safety statute, ordinance or regulation to be a cutoff luminaire.
  4. Temporary outdoor lighting.
  5. Lighting required and regulated by the Federal Aviation Administration or the Coast Guard.
  6. Lighting for public streets, roadways, highways, and traffic signage lighting, including lighting for driveway entrances occurring in the public right-of-way. Luminaires that illuminate the public right of way including publicly maintained or utility-maintained sidewalks and bikeways.
  7. Lighting for sports and athletic fields, and children’s playgrounds.
  8. 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.
  9. Lighting of tunnels, bridges, stairs, wheelchair elevator lifts for American with Disabilities Act (ADA) compliance, and ramps that are not parking garage ramps.
  10. In theme parks: outdoor lighting only for themes and special effects.
  11. 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.
  12. 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.

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