Pacifica, CA Accessory Structures: ADU Rules (2026)

22, governs accessory dwelling units citywide. 5 itself can be the basis for denying or delaying an ADU building permit. 453(b) confirms ADUs are permitted on any residentially zoned site, or a commercially zoned site that allows residential use, that already has a qualifying primary dwelling. 453(c) caps total floor area at 1,200 square feet and sets a fifteen-foot front setback, four-foot side setback, and four-foot rear setback. Height is limited to twenty-five feet or the height of the primary dwelling, whichever is less, dropping to sixteen feet if the primary dwelling is under sixteen feet tall or the unit sits close to the front, side, or rear lot line.

Units of 800 square feet or less get relief from the lot coverage and landscaping standards that otherwise apply, and any detached ADU over 800 square feet is barred entirely from a site fronting an unpaved street or a street twenty-six feet wide or narrower, a limit the City Council adopted to protect fire apparatus access. 453(h)(6) waives that requirement entirely for ADUs within a half mile of public transit, in a historic district, 800 square feet or smaller, or served by a nearby car-share vehicle.