Cal. Health & Safety Code § 17958.7

(a) 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. Such a finding shall be available as a public record. A copy of those findings, together with the modification or change expressly marked and identified to which each finding refers, shall be filed with the California Building Standards Commission. No modification or change shall become effective or operative for any purpose until the finding and the modification or change have been filed with the California Building Standards Commission.
(b) The California Building Standards Commission may reject a modification or change filed by the governing body of a city or county if no finding was submitted.
(c) Commencing October 1, 2025, to June 1, 2031, inclusive, the commission shall reject a modification or change to any building standard affecting a residential unit and filed by the governing body of a city or county, unless one of the following conditions is met:
1. (1) The changes or modifications are substantially equivalent to changes or modifications that were previously filed by the governing body of the city or county and were in effect as of September 30, 2025.
2. (2) The commission deems those changes or modifications necessary as emergency standards to protect health and safety.
3. (3) The changes or modifications relate to home hardening.
4. (4) The building standards relate to home hardening and are proposed for adoption by a local fire prevention district pursuant to Section 13869.7.
5. (5) The changes or modifications are necessary to implement a local code amendment that is adopted to align with a general plan approved on or before June 10, 2025, and that permits mixed-fuel residential construction consistent with federal law while also incentivizing all-electric construction as part of an adopted greenhouse gas emissions reduction strategy.
6. (6) The changes or modifications are related to administrative practices, are proposed for adoption during the intervening period pursuant to Section 18942, and exclusively result in any of the following:
  1. (A) Reductions in time for a local agency to issue a postentitlement permit.
  2. (B) Alterations to a local agency’s postentitlement fee schedule.
  3. (C) Modernization of, or adoption of, new permitting platforms and software utilized by the local agency.
  4. (D) Reductions in cost of internal operation for a local agency.
  5. (E) Establishment, alteration, or removal of local programs related to enforcement of building code violations or complaints alleging building code violations.
(d)
1. (1) The commission, in determining that a modification or change meets any of the criteria in paragraph (1) to (5), inclusive, of subdivision (c), may rely on a statement by the local agency to that effect.
2. (2) The changes or modifications made pursuant to paragraph (6) of subdivision (c) may be filed with the commission and shall be reviewed by the commission, in consultation with the Department of Housing and Community Development, within 60 days of receipt, if requested by the local agency.