California building code

Codes in force in California

Each code family with the edition and the date it took effect, as the adopting agency or statute states them.

Adopted by: California Building Standards Commission³.

Scope, amendments and transition rules

International Building Code (IBC)

Scope

Statewide minimum; local governments may go further³

Applies to

All occupancies throughout the state³

Local amendments allowed?

Allowed on findings; restricted for residential units October 1, 2025 to June 1, 2031³

Amendments

Cal. Health & Safety Code §§ 17958.5, 17958.7, 18941.5³

Transition period

Code in effect when the permit application is submitted applies³

Next edition (not yet in force)

2028 edition, effective January 1, 2029⁴

International Residential Code (IRC)

Scope

Statewide minimum; local governments may go further³

Applies to

All occupancies throughout the state³

Local amendments allowed?

Allowed on findings; restricted for residential units October 1, 2025 to June 1, 2031³

Amendments

Cal. Health & Safety Code §§ 17958.5, 17958.7, 18941.5³

Transition period

Code in effect when the permit application is submitted applies³

Next edition (not yet in force)

2028 edition, effective January 1, 2029⁴

National Electrical Code (NEC)

Scope

Statewide minimum; local governments may go further³

Applies to

All occupancies throughout the state³

Local amendments allowed?

Allowed on findings; restricted for residential units October 1, 2025 to June 1, 2031³

Amendments

Cal. Health & Safety Code §§ 17958.5, 17958.7, 18941.5³

Transition period

Code in effect when the permit application is submitted applies³

Next edition (not yet in force)

2028 edition, effective January 1, 2029⁴

Uniform Mechanical Code (UMC)

Scope

Statewide minimum; local governments may go further³

Applies to

All occupancies throughout the state³

Local amendments allowed?

Allowed on findings; restricted for residential units October 1, 2025 to June 1, 2031³

Amendments

Cal. Health & Safety Code §§ 17958.5, 17958.7, 18941.5³

Transition period

Code in effect when the permit application is submitted applies³

Next edition (not yet in force)

2028 edition, effective January 1, 2029⁴

Uniform Plumbing Code (UPC)

Scope

Statewide minimum; local governments may go further³

Applies to

All occupancies throughout the state³

Local amendments allowed?

Allowed on findings; restricted for residential units October 1, 2025 to June 1, 2031³

Amendments

Cal. Health & Safety Code §§ 17958.5, 17958.7, 18941.5³

Transition period

Code in effect when the permit application is submitted applies³

Next edition (not yet in force)

2028 edition, effective January 1, 2029⁴

Wildland-Urban Interface Code (IWUIC)

Scope

Statewide minimum; local governments may go further³

Applies to

All occupancies throughout the state³

Local amendments allowed?

Allowed on findings; restricted for residential units October 1, 2025 to June 1, 2031³

Amendments

Cal. Health & Safety Code §§ 17958.5, 17958.7, 18941.5³

Transition period

Code in effect when the permit application is submitted applies³

Next edition (not yet in force)

2028 edition, effective January 1, 2029⁴

International Fire Code (IFC)

Scope

Statewide minimum; local governments may go further³

Applies to

All occupancies throughout the state³

Local amendments allowed?

Allowed on findings; restricted for residential units October 1, 2025 to June 1, 2031³

Amendments

Cal. Health & Safety Code §§ 17958.5, 17958.7, 18941.5³

Transition period

Code in effect when the permit application is submitted applies³

Next edition (not yet in force)

2028 edition, effective January 1, 2029⁴

International Existing Building Code (IEBC)

Scope

Statewide minimum; local governments may go further³

Applies to

All occupancies throughout the state³

Local amendments allowed?

Allowed on findings; restricted for residential units October 1, 2025 to June 1, 2031³

Amendments

Cal. Health & Safety Code §§ 17958.5, 17958.7, 18941.5³

Transition period

Code in effect when the permit application is submitted applies³

Next edition (not yet in force)

2028 edition, effective January 1, 2029⁴

State code: Part 6 California Energy Code

Scope

Statewide minimum; local governments may go further³

Applies to

All occupancies throughout the state³

Local amendments allowed?

Allowed on findings; restricted for residential units October 1, 2025 to June 1, 2031³

Amendments

Cal. Health & Safety Code §§ 17958.5, 17958.7, 18941.5³

Transition period

Code in effect when the permit application is submitted applies³

Next edition (not yet in force)

2028 edition, effective January 1, 2029⁴

State code: Part 11 California Green Building Standards Code, also known as CALGreen

Scope

Statewide minimum; local governments may go further³

Applies to

All occupancies throughout the state³

Local amendments allowed?

Allowed on findings; restricted for residential units October 1, 2025 to June 1, 2031³

Amendments

Cal. Health & Safety Code §§ 17958.5, 17958.7, 18941.5³

Transition period

Code in effect when the permit application is submitted applies³

Next edition (not yet in force)

2028 edition, effective January 1, 2029⁴

How California adopts building codes

Cal. Health & Safety Code §§ 18938, 18941.5, 17958, 17958.5, 17958.7, 18942, 18930(g) · in effect January 1, 2018³

• Statewide; applies to all occupancies. The building standards contained in the model codes described in Section 18916 and adopted by reference into the California Building Standards Code and any other building standards adopted into the California Building Standards Code shall apply to all occupancies throughout the state and shall become effective 180 days after publication in the California Building Standards Code by the California Building Standards Commission or at a later date after publication established by the commission.³
• 2025 California Building Standards Code (Title 24), effective January 1, 2026. The 2025 California Building Standards Code (Cal. Code Regs., Title 24) will be published July 1, 2025, with an effective date of January 1, 2026.²
• Code revised every three years. The commission shall publish, or cause to be published, editions of the code in its entirety once every three years.³
• State code automatically applies if a city or county adopts no changes. If any city or county does not amend, add, or repeal ordinances or regulations to impose those requirements or make changes or modifications in those requirements upon express findings, the provisions published in the California Building Standards Code or the other regulations promulgated pursuant to Section 17922 shall be applicable to it and shall become effective 180 days after publication by the California Building Standards Commission.³
• Local changes need climatic, geological or topographical findings. Except as provided in subdivision (c) and in Section 17922.6, the governing body of a city or county, before making any modifications or changes pursuant to Section 17958.5, shall make an express finding that such modifications or changes are reasonably necessary because of local climatic, geological, or topographical conditions.³
• Residential local-change moratorium October 1, 2025 to June 1, 2031. Commencing October 1, 2025, to June 1, 2031, inclusive, a city or county shall not make a change or modification as described in subdivision (a) or (b), including to green building standards, that is applicable to residential units, unless one of the following conditions is met…³
• State residential code freeze October 1, 2025 to June 1, 2031. Commencing October 1, 2025, to June 1, 2031, inclusive, proposed building standards affecting residential units shall not be considered, approved, or adopted by the commission or any other adopting agency, unless any of the following conditions are met…³
• Supplements to the 2025 edition, effective July 1, 2027. These code changes will result in supplements to the 2025 edition of Title 24, effective July 1, 2027.⁵
• 2028 edition, effective January 1, 2029. These code changes will result in the 2028 edition of the California Building Standards Code, Title 24 of the California Code of Regulations, effective January 1, 2029.⁴
• Part 7 emergency supplement effective January 1, 2026. Emergency Supplement — Part 7 Effective January 1, 2026…²
• Non-urgency statutes from a regular session take effect January 1 after a 90-day period from enactment. …a statute enacted at a regular session shall go into effect on January 1 next following a 90-day period from the date of enactment of the statute…³

Applies to

All occupancies throughout the state³

Can local rules be stricter?

Yes³

Residential code in California cities

The edition each city enforces, from the city’s own adoption page or ordinance.

For permits, exemptions and owner-builder rules, see California building permits. To compare editions across states, see the code adoption map.