Gardena, CA Building Safety: Fire Sprinkler Requirements (2026)

Gardena Municipal Code § 15.06.060 amends Section 903.2 of the 2022 California Building Code and adds Section 903.2.13, Expansion of Existing Buildings. The base rule keeps every standard CBC trigger in Sections 903.2.1 through 903.2.21 in force, covering uses such as multi-family buildings, group assembly and high-hazard occupancies. The city's own addition applies the sprinkler mandate retroactively: an automatic sprinkler system becomes required in an existing building undergoing alteration or expansion when the expansion exceeds 50 percent of the existing gross floor area, or when the cost of remodeling, expansion or improvement exceeds 50 percent of the value of the existing structure as determined by the Building Official.

The Building Official calculates that 50-percent valuation threshold using the same construction-value method set out at § 15.06.040 for permit fees, which counts all finish work, electrical, plumbing, HVAC and fire-extinguishing systems toward the project's total value. Because the trigger is based on cumulative floor area and dollar value rather than occupancy type alone, it can reach single-tenant retrofits and additions to older commercial and residential structures across Gardena that would not otherwise need sprinklers under the base CBC. Any permit for such alteration work must be obtained through the Building Division of the Community Development Department, and work started before the permit is issued quadruples the plan-check and permit fee under § 15.06.040(B).