California ADU rules - popularity rank #4
San Francisco ADU rules include state and local paths across single-family and multifamily cases. The city page separates official source-backed rule rows from parcel-specific feasibility questions.
Based on 13 curated rule paths from official sources. Last reviewed June 2026. Use this page as the rule starting point, then run the address check to see which path matches your lot.
Popularity rank
#4 California ADU market
Rule paths
13 curated ADU rule sets
Detached max size
850-1,000 sq ft by bedrooms
Side / rear setbacks
4 ft state baseline
Height
18 ft plus roof-pitch allowance
Primary source
SF Planning ADU page
Rule snapshot
These sections mirror the questions homeowners search for: size, setbacks, parking, permit workflow, and which ADU type is available. The rows stay source-backed and avoid turning a city rule into parcel approval.
Planning a garage conversion ADU?
Read the California garage conversion guide, then run the address check to match the city baseline to the actual lot.
Estimating ADU permit cost?
Permit cost depends on the fee stack, ADU type, size, waivers, and plan-check path for this city.
San Francisco has curated State and Local rule families, which keeps the city page from flattening separate review paths.
The state detached path is bedroom-sensitive, with setback and height rows kept separate from size.
San Francisco's local ADU options can depend on the building, property type, and the specific program path.
Why this is a starting point
Competitor rule pages often stop at a city summary. The useful next step is matching those rules to an actual lot, because zoning, parcel geometry, overlays, and selected ADU type decide what a homeowner should do next.
San Francisco has curated State and Local paths so the page can show a source-backed starting point while reports compare applicable rule families.
The data covers single-family and multifamily ADU cases, including detached, attached, conversion, and JADU-style paths where official sources support them.
The state detached path includes 850 sq ft for studio or one-bedroom units and 1,000 sq ft for two-bedroom or larger units, with setback and height rows kept separate.
Free ADU Check
The city page gets the search visitor in the door. The ADU Check turns the visit into a property-specific report path.
Start free address checkThe check matches the typed address to jurisdiction, zoning, parcel context, and the closest stored ADU rule path.
Detached, attached, conversion, garage conversion, and JADU paths are handled separately when the city source supports them.
The report keeps official rule text separate from parcel-specific caveats, so a homeowner can see the rule and the remaining risk.
Official links
These are outbound official sources from HomeFeasible's reviewed ADU rule collection. They are here for verification and trust; the address check is the next step for a property-specific answer.
Primary rule page
https://sfplanning.org/accessory-dwelling-units
Local ADU chart
https://sfplanning.org/sites/default/files/documents/adu/Local_ADU_Comparison_Chart.pdf
State ADU program
https://sfplanning.org/resource/planning-director-bulletin-no-3-state-accessory-dwelling-unit-program
Internal links
Top questions
Summaries reflect official source links and the structured ADU rule data collected for HomeFeasible's first launch. Regulations change and individual parcels vary; verify current requirements with the city planning department or run a parcel-specific check before making decisions.
Canonical URL: https://homefeasible.com/city/san-francisco/adu
