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Permit guides

ADU Permits in San Francisco: a Homeowner's Guide

Two ADU programs, rent-control implications, and why SF takes longer — in plain language.

Last updated October 2026. Rules change; always confirm current requirements with the city before you build.

Who handles your permit

San Francisco runs ADUs through two agencies: the Planning Department reviews first (ADU counter at 1660 Mission Street — CPC.ADU@sfgov.org, (415) 865-5738), then the Department of Building Inspection (DBI) reviews for building code. Buildings with three or more units also get Fire Department review, and Public Works and the Public Utilities Commission often weigh in. Start at the Planning ADU counter before you draw anything — staff give real-time feedback on what your lot will need.

What you can build

Two programs — pick carefully

San Francisco offers a State ADU program and a Local ADU program, and the choice has consequences. The Local program comes with extras: a public notice posted on the building at least 15 days before you apply (with photos sent to the Rent Board), a possible Historic Resource Review (most SF properties are unevaluated Category B), a recorded Notice of Special Restrictions — and, critically, a Costa Hawkins agreement.

DBI pre-approved detached plans

Under the state's AB-1332 framework, DBI pre-approves standardized detached ADU construction plans for a flat $956 review fee (submitted to dbi.adurequest@sfgov.org). A pre-approved plan still needs a site-specific submittal — foundation design, soils, setbacks, fire separation — but skips the full design review. Note the exclusions: pre-approved plans can't be used in slope protection areas, landslide and liquefaction zones, Maher Zones, or flood zones, which covers a lot of San Francisco's hillsides.

What goes into the submittal

• DBI screening form confirming program eligibility
• Site-specific plan set: adjacent lots, true north, dimensions, usable open space, street trees
• Soils report and site survey where required
• Fire separation, egress, and sprinkler details
• SF Unified School District fees and drainage plan

Where applications usually get stuck

• Soils and geography. Geotechnical surprises are the norm on SF lots — budget the investigation early.
• Historic review. Category B properties with street-visible alterations can trigger a full historic resource evaluation.
• The multi-agency checklist. Planning, DBI, Fire, Public Works, PUC — each with its own requirements; a pre-application meeting (fees apply) is worth it.
• Program choice. Picking the Local program for its flexibility without understanding the rent-control and notice strings attached.