San Luis Obispo County, CA Building Safety: Fire Sprinkler Requirements (2026)

1, a local table setting fire sprinkler requirements by structure type. New construction, including new dwellings and mobile homes and commercial coaches, must have sprinklers throughout with no minimum size threshold, per California Building Code and California Residential Code requirements. Residential accessory structures between 1,000 and 3,000 square feet need sprinklers unless the structure meets an exceptions list: no conditioned or habitable space, no second story except a loft limited to one-third of the floor area, at least two exits including a side-hinge swinging pedestrian door, workshops or offices capped at ten percent of floor area, compliance with the Wildland Urban-Interface ignition-resistant construction standards, and no use as a place of employment, public assembly, or commercial building.

Agricultural structures between 3,000 and 5,000 square feet accessory to livestock or crop operations need sprinklers unless similarly excepted, and must sit at least one hundred feet from the property line and fifty feet from other structures. Pole barns, covered arenas, and greenhouses used for hay storage or riding with no public access are exempt outright if built one story and set sixty feet from all sides per the Building Code. Floor area for these calculations includes all combustible areas attached to the structure, such as garages, patio covers, and workshops.