California — Code Adoption Summary
Adoption model: Statewide-mandatory (Title 24, California Building Standards Code). Locals may amend with findings filed with CBSC; energy cannot be weakened.
Last verified: 2026-07-02
Confidence: verified
Primary sources: CA Building Standards Commission — https://www.dgs.ca.gov/BSC · CA Energy Commission (Title 24 Part 6) — https://www.energy.ca.gov · ICC CA codes — https://codes.iccsafe.org/codes/california
Statewide adopted codes — 2025 Title 24 (effective 2026-01-01; triennial cycle)
As of 2026-07-02 the 2025 Title 24 edition is in effect statewide. (The prior 2022 edition ran 2023-01-01 → 2025-12-31.)
| Code family | Title 24 Part | Adopted edition | Notes | Source |
|---|
| Building | Part 2 — CBC 2025 | 2024 IBC base + CA amendments | | dgs.ca.gov/BSC |
| Residential | Part 2.5 — CRC 2025 | 2024 IRC base | | " |
| Electrical (NEC) | Part 3 — CEC 2025 = NEC 2023 + CA amendments | 2022 CEC was NEC 2020; 2025 CEC = NEC 2023 | Low Voltage Nation / CEC | |
| Mechanical | Part 4 — CMC 2025 (UMC-based) | IAPMO UMC + CA amend. | | " |
| Plumbing | Part 5 — CPC 2025 (UPC-based) | California is a UPC state (IAPMO) | | " |
| Energy | Part 6 — 2025 Building Energy Efficiency Standards | strictest in US; electrification/heat-pump baselines | eff. 2026-01-01 | energy.ca.gov |
| Green | Part 11 — CALGreen 2025 | mandatory green building | | dgs.ca.gov/BSC |
| Fire | Part 9 — CFC 2025 | | Office of State Fire Marshal | osfm.fire.ca.gov |
Solar PV / ESS / EV
| Item | Status | Source |
|---|
| NEC solar (690/705/706) | Via CEC 2025 = NEC 2023 + CA amendments | CEC 2025 |
| Mandatory solar | Title 24 Part 6 requires PV (and often battery storage) on most new residential + many nonresidential buildings | energy.ca.gov |
| SolarAPP+ | State-backed instant residential PV/storage permitting adopted by many CA jurisdictions | solarapp.gov |
| EV charger (NEC 625) + EV-ready | CALGreen + Part 6 require EV-ready / EVSE parking ratios | CALGreen 2025 |
Adoption model & precedence
- Title 24 applies statewide. Local jurisdictions may adopt more-stringent amendments but must file express findings with the California Building Standards Commission; energy (Part 6) cannot be made weaker.
- Many cities have reach codes (all-electric / stricter energy) filed with the CEC.
- AHJ = local building department (e.g., LADBS in Los Angeles).
Major cities / counties with their own amendments
| Jurisdiction | County | Own code? | Key amendments | Building dept. |
|---|
| Los Angeles | LA | Title 24 + LABC/LAEC | extensive LA amendments; seismic; LADBS | ladbs.org |
| San Francisco | SF | Title 24 + SF amend. | SF green/energy reach codes | sf.gov/dbi |
| San Diego | San Diego | Title 24 + local | climate-action reach codes | sandiego.gov |
| San Jose | Santa Clara | Title 24 + all-electric reach | electrification reach code | sanjoseca.gov |
| Sacramento | Sacramento | Title 24 + local | | cityofsacramento.org |
AHJ fallback (when local adoption is unverified)
- State baseline that always applies: 2025 Title 24 (CEC = NEC 2023, CPC = UPC, Part 6 energy, CALGreen).
- Likely AHJ: city building dept (LADBS, SF DBI, etc.), else county.
- Action: check for a local reach code / all-electric ordinance and local seismic amendments before design.
Change log
- 2026-07-02 — created; confirmed 2025 Title 24 in effect (eff. 2026-01-01), CEC 2025 = NEC 2023, CPC = UPC. Prior 2022 CEC = NEC 2020.
