The California Energy Commission’s Sept. 9 business-meeting materials put three related building-code actions on the same agenda: a formal determination that California’s 2025 Energy Code meets or exceeds the 2024 International Energy Conservation Code for residential buildings, approval of CBECC 2025.3.0, and updates to the 2025 Alternative Calculation Method Reference Manual.
In the residential certification materials, the commission says it adopted the 2025 Energy Code in August 2024, that the code took effect Jan. 1, 2026 and that California must certify its residential provisions by Dec. 30, 2026 under federal law. The backup packet says the 2025 Energy Code meets or exceeds the 2024 IECC, and the accompanying CEQA memo says the certification is not a project or, alternatively, qualifies for CEQA’s common-sense exemption. CEC Item 8 residential certification materials
The software item proposes approval of CBECC 2025.3.0, the state’s public-domain compliance software for the 2025 Energy Code. According to the staff materials, the update aligns with the revised ACM manuals and would take effect for permit applications filed on or after Dec. 18, 2026. The packet also says the commission would adopt a CEQA finding that the software update is not a project or is exempt.
For the manual item, staff recommended certifying the updated Alternative Calculation Method Reference Manual for the 2025 Building Energy Efficiency Standards and adopting a CEQA exemption finding. The materials say the update is intended to support public-domain and third-party compliance software tied to the 2025 Energy Code.
Taken together, the three items would define the rulebook, software and reference materials builders, designers and permitting officials use to show compliance with California’s 2025 Energy Code.
