Can you build an ADU in San Francisco, CA?
SF Planning states the ADU program is available citywide in all zoning districts that permit residential use. Project-specific building type and program rules still need to be checked, but citywide availability makes ADUs one of the clearest paths supported by the source set.
Confidence: high · Last researched May 2026
Accessory Dwelling Unit (ADU) rules
San Francisco's ADU program is available citywide in all zoning districts that permit residential use.
- Program available citywide to all zoning districts that permit residential use
- As of January 2020, California laws govern ADUs statewide and allow ADUs to be added to single-family and multi-family buildings
- Recognized ADU types include converted, attached, detached, and junior ADUs
- A junior ADU converts up to 500 square feet of space in a single-family structure
- A junior ADU requires owner-occupancy in either the remaining portion of the single-family home or the newly created JADU if the JADU shares sanitation facilities with the main residence
- Accessory dwelling units are ineligible for the Short-Term Rental program
- Unauthorized existing units may in some cases be legalized through a separate checklist and process
Related questions
Are ADUs allowed in San Francisco, CA?
San Francisco's ADU program is available citywide in all zoning districts that permit residential use.
Full investor analysis
You've seen the general rule. The full San Francisco, CA report shows which districts allow ADUs by-right vs. by special permit, the approval path and timeline, and the overlay/flood constraints that quietly kill ADU projects here. First town report is free.
Get the full San Francisco, CA report free →More about San Francisco, CA zoning
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This summary is AI-generated from public municipal sources and is not legal, engineering, or land-use advice. Always verify zoning with San Francisco, CA officials before making decisions.
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