Pismo Beach, CA Building Safety: Fire Sprinkler Requirements (2026)

Section 15.08.020 amends the California Residential Code, and its amended Section R309.2 says an automatic residential fire sprinkler system shall be installed in one- and two-family dwellings. Two exceptions are printed. Exception 1 covers existing dwellings not already provided with a system where additions or alterations do not increase the existing floor area by more than 1,000 square feet or create an additional dwelling unit. Exception 2 covers an accessory dwelling unit only if all four conditions are met: the unit meets the definition of an Accessory Dwelling unit in Government Code Section 65852.2, the existing primary residence does not have automatic fire sprinklers, the accessory detached building does not exceed 1,200 square feet, and the unit is on the same lot as the primary residence.

Amended R309.3.1.2 requires sprinklers to protect all areas of a dwelling unit. Exceptions cover attics, crawl spaces and normally unoccupied concealed spaces without fuel-fired appliances (where fuel-fired equipment is present, a sprinkler goes above the equipment), clothes closets, linen closets and pantries not exceeding 24 square feet with gypsum board surfaces, bathrooms not more than 55 square feet, and detached garages where floor area does not exceed 1,000 square feet, carports with no habitable space above, and open attached porches. Added R309.3.5.4 sets the minimum water supply for a system designed under R313 or NFPA 13D at not less than a 1-inch nominal pipe size for the service lateral from the water main to the water meter location and not less than a 1-inch water meter.

The fire code carries a matching rule. Section 8.08.010 T rewrites California Fire Code Section 903.2 so that a Group R, Division 3 building not more than three stories above grade plane complies with the Residential Code R309 sprinkler requirements, and Section 903.3.5.3 repeats the 1-inch lateral and meter minimum. For accessory dwelling units, § 17.117.090 of the 1983 Zoning Ordinance and § 17.38.155 of the 1998 Zoning Code each print that ADUs and JADUs shall not be required to include fire sprinklers if they are not required for the primary unit.