San Francisco Zoning Districts & Building Rules
Data version: Q2 2026 · Last updated 2026-05-13
TL;DR. San Francisco has one of the most complex zoning systems in the nation with over 90 zoning districts, separate height and bulk maps, and neighborhood-specific plans layered on top. The city uses form-based categories: Residential (RH, RM, RC), Neighborhood Commercial (NC), Downtown Commercial (C-3), and Production/Distribution/Repair (PDR). Buildability™ checks your exact district, height limit, and special use designations instantly.
SF zoning districts explained
RH-1 (Residential, House One-Family): single-family with ADUs, 40 ft height typical. RH-2 (Two-Family): duplexes allowed, SB 9 enables lot splits. RM-1/RM-2 (Residential Mixed): low-density apartments at 1 unit per 800 sq ft lot area. NC (Neighborhood Commercial): ground-floor retail with residential above, height varies 26-85 ft by neighborhood plan. C-3 (Downtown Commercial): high-rise towers up to 1,200 ft in Transbay district with 9:1 FAR.
Height and bulk controls
SF uses a separate height and bulk map overlaid on zoning districts. Residential neighborhoods: typically 40 ft. Mid-Market and SoMa: 65-130 ft. Downtown/Financial District: 200-700+ ft. Transbay area: up to 1,200 ft. Bulk controls limit floorplate size above certain heights to preserve light and air. Your property may have different height limits than adjacent parcels.
Discretionary Review risk
Discretionary Review (DR) is unique to San Francisco. Neighbors can request the Planning Commission review any project that meets all zoning requirements. DR adds 3-6 months and may result in project modifications. Section 311 neighborhood notification is required for many projects. This process makes SF permitting among the most unpredictable in the country. Buildability™ flags DR risk as part of your approval friction score.
Permit timeline and costs
DBI (Department of Building Inspection) handles building permits. SF Planning handles land use approvals. Simple residential: 8-16 weeks. ADUs: 6-9 months. Larger projects with environmental review: 12-24+ months. Permit and impact fees among the highest in the U.S. — residential fees can exceed $50,000 per unit. Construction costs average $500-$800/sq ft.
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