San Francisco Zoning, Planning & Building Codes

The San Francisco Planning Code governs how land may be used across the city — what can be built, where, and at what density — while the San Francisco Building Code governs how it is constructed. Land use is organized into zoning districts: RH (Residential, House), RM (Residential, Mixed), RC (Residential-Commercial) and the various NC (Neighborhood Commercial) districts. Sorting out which district applies to a parcel, and what it allows, is exactly the kind of question GoCodebook answers with citations.

San Francisco layers its own rules on top of the statewide California Building Standards Code and state housing laws. Recent density-exception ordinances now allow up to four units per lot (and up to six on corner lots) in many RH districts, and the city runs its own Accessory Dwelling Unit (ADU) program under the Planning Code. Because outcomes depend on the specific district, lot and building age, a plain-English, cited answer saves time before you file.

San Francisco's residential districts run from RH-1 (one house per lot) and RH-1(D) (detached, with side yards) through RH-2 and RH-3 (two and three units), up to RM districts that mix houses and apartments and RC and NC districts that combine residential with ground-floor commercial uses. Each district sets its own controls on density, height, bulk, setbacks and permitted uses.

Many projects also trigger conditional use authorization or discretionary review before the Planning Commission, rather than being approved purely over the counter. To see where the city has detailed coverage, check our coverage page, and compare neighboring peninsula rules in Palo Alto or Cupertino.

Construction permits are issued and inspected by the Department of Building Inspection (DBI), which enforces the San Francisco Building, Housing and related codes — themselves amendments to the statewide California Building Code and Residential Code. Most projects move through Planning review for zoning compliance first, then DBI for the building permit and inspections.

A change of use — for example, converting commercial space to residential, or legalizing a unit — often requires both Planning sign-off and a DBI permit. DBI also handles housing-code enforcement and habitability complaints. Browse the full set of statewide model codes on our California Building Standards Code hub.

San Francisco has its own Rent Ordinance. As a general rule, residential units in buildings issued a first certificate of occupancy before June 13, 1979 are subject to rent-increase limits, while units built after that date are exempt from the rent cap but generally still covered by the ordinance's just-cause eviction protections. This local ordinance is stricter than, and operates alongside, the statewide AB 1482 rent cap — see our rent control overview.

The city runs a local ADU program under the Planning Code that lets owners add accessory dwelling units to existing residential buildings, subject to its own controls. Because ADU and rent-control coverage both hinge on the building's age, type and history, the safest move is to check the specific property. Compare how rent-controlled Los Angeles handles similar questions.