Title 24 is the California Building Standards Code. In construction conversation it usually means Part 6, the energy code, which sets requirements for insulation, windows, heating and cooling, water heating and solar. The 2025 edition took effect January 1, 2026 and applies to permit applications filed on or after that date. Applications filed by December 31, 2025 still run under the 2022 code.
When it applies to you
New construction, additions, ADUs, and any remodel that replaces windows, heating and air, a water heater, roofing or lighting. Even a kitchen remodel has to use efficient lighting, and any new window has to meet the current standard.
What the 2025 code changed for new homes
Heat pumps for both space heating and water heating are now the baseline assumption for most new single-family homes, which is a shift from the 2022 code. Solar is still required. Battery storage is mostly a readiness requirement rather than a mandate to install batteries, so be careful with anyone who tells you otherwise. Window and insulation standards tightened, and the code switched to a new long-term cost metric for showing compliance.
In practice
An energy consultant prepares a compliance report that goes in with your drawings, and a certified rater verifies some of it during construction. It is a line item, not a drama. We build it into the budget and the schedule from the start.
Los Angeles County figures, reviewed 2026-10-29 by America General Contractors, California contractor licence CSLB 1083262. Planning ranges, not a quote, and not legal advice. We confirm the current rules for your parcel before anything gets drawn.
Related questions
Who does this work
Kitchen & Bathroom Remodeling
New kitchens and bathrooms, from a weekend-level refresh to moving walls and plumbing.
ADU & Garage Conversion
A second home on your lot: a backyard unit, a converted garage, or a unit carved out of the house.