South San Francisco, CA Building Setbacks & Zoning: Structure Height Limits (2026)

Building height limits in unincorporated San Mateo County depend on the zoning district and any overlay. Chapter 8.336 (Height: General Provisions and Exceptions) sets baseline and special rules. For institutional and public/semi-public buildings — schools, churches, hospitals, and similar — Section 8.336.010 allows heights up to 75 feet, provided front, rear, and side yards are increased one foot for each foot the building exceeds the district's normal limit. Section 8.336.020 grants a downhill-slope exception: where a lot's average slope is steeper than a 1-foot rise or fall per 7 feet from the street grade at the front lot line, one additional story is permitted on the downhill side, without exceeding the district's height limit. Section 8.336.040 caps most structures at 150 feet (except in A-1, A-2, and M-2 districts) and limits certain rooftop appurtenances. District-specific limits control for most homes: in the Planned Agricultural District (Section 8.106.090), no residential or commercial structure may exceed 3 stories or 36 feet, except that in the Midcoast Local Coastal Program Update Project Area no residential structure may exceed 28 feet — and if any portion of a structure is used for residential purposes, the entire structure is limited to 28 feet. In agricultural districts, well derricks, windmills, and tank houses may reach 60 feet (Section 8.336.040). Because the applicable limit depends on the base district, combining 'S' district, and overlays, confirm the height limit for a specific parcel with Planning and Building.