ADU (Accessory Dwelling Unit) Permit in San Francisco (2026)
ADU (Accessory Dwelling Unit) permit requirements, fees, and process for San Francisco, CA. Find out if you need a permit and how to apply.
Yes, a ADU (Accessory Dwelling Unit) permit is required in San Francisco, CA.
A ADU (Accessory Dwelling Unit) permit is required in San Francisco, CA. The San Francisco Department of Building Inspection (DBI) handles permit applications for San Francisco. Below you will find the current thresholds, fees, and process for obtaining a adu (accessory dwelling unit) permit in San Francisco.
When Is a Permit Required?
When a ADU (Accessory Dwelling Unit) Permit Is Required in San Francisco: All ADUs and JADUs require building permit
Permit Fees
ADU (Accessory Dwelling Unit) Permit Fees in San Francisco: $3,000–$10,000 typical total. Estimated timeline: 2-6 weeks plan check via SF DBI ADU Program.
Estimated timeline: 2-6 weeks plan check via SF DBI ADU Program
How to Get a ADU (Accessory Dwelling Unit) Permit in San Francisco
Verify whether your project meets the permit threshold in San Francisco: All ADUs and JADUs require building permit.
Prepare your permit application and plans. Contact the San Francisco Department of Building Inspection (DBI) at https://sfdbi.org/ for required documentation.
Submit your application online at https://dbidocs.sfgov.org/ or in person at the San Francisco Department of Building Inspection (DBI).
Pay the permit fee: $3,000–$10,000 typical total.
Wait for plan check approval. Estimated timeline: 2-6 weeks plan check via SF DBI ADU Program.
Schedule required inspections through https://sfdbi.org/inspection-scheduling. All inspections must pass before project is finalized.
Important: State law mandates ministerial approval within 60 days. SF DBI ADU Program provides pre-approved standard plans. Planning pre-approval required in some cases. SF Planning ADU eligibility checker: https://sfplanning.org/resource/accessory-dwelling-units
Additional Requirements
- SF Planning pre-approval for some configurations
- DBI building permit required
- Separate utility connections may be required
San Francisco Department of Building Inspection (DBI)
Phone: (415) 558-6088
Website: https://sfdbi.org/
Online Permits: https://dbidocs.sfgov.org/
Hours: Mon-Fri 8:00am-4:00pm (public counter); permit applications online 24/7
Frequently Asked Questions
Can I build an ADU (in-law unit) in San Francisco?
Yes. California state law requires San Francisco to permit ADUs by-right on all residential lots. You can build a detached ADU up to 1,200 sqft, an attached ADU, a garage conversion, or a Junior ADU (JADU) up to 500 sqft within your existing home. No owner-occupancy requirement applies. SF DBI processes ADU permits ministerially within 60 days. The SF Planning ADU Program provides pre-approved plans for common configurations.
What are San Francisco's Airbnb rules?
Short-term rentals in SF require a Certificate of Registration from the Office of Short-Term Rentals ($450/year). Your unit must be your primary residence — you must live there at least 275 days per year. Whole-home (unhosted) rentals are capped at 90 nights per year. Hosted rentals (you're present) have no night cap. Penalties for non-compliance are $484 per day. Register at ostr.sfgov.org.
What zoning system does San Francisco use?
San Francisco uses its Planning Code (not Municipal Code) for zoning. Residential zones are RH (House) and RM (Mixed Residential) — ranging from RH-1 (single-family) to RM-4 (high-density apartments). Neighborhood Commercial Transit (NCT) zones allow retail below residential. The Planning Code emphasizes rear yard preservation — the typical requirement is 25% of lot depth or 15 ft minimum for rear yards in most residential zones.
Do I need a permit to run a business from my home in San Francisco?
Yes. A Home Occupation Permit ($148 fee) is required for any business operated from a residence in San Francisco. Restrictions apply: no clients visiting, no non-resident employees, no external signs, and business use must be secondary to residential use. Violations can result in code enforcement action.
What are the front yard setback requirements in San Francisco?
In RH-1 (single-family) zones, the standard front setback is 15 feet from the front property line. However, SF Planning Code requires that new construction match the prevailing setback of the block face — if neighboring homes have deeper setbacks, yours must match. Side yards are typically 0 feet in SF's characteristic attached rowhouse pattern. Rear yards must be at least 25% of lot depth (minimum 15 ft).
Are solar panels required on new homes in San Francisco?
Yes. California's Title 24 Energy Code (effective 2020 for single-family) requires solar PV on all new low-rise residential construction. San Francisco also adopted its own solar mandate for commercial buildings in 2016. Properties in SF historic districts need Planning Department approval for solar panels visible from the street, but this cannot be denied for code-compliant systems.
How do I find the zoning for my San Francisco property?
Use the SF Planning Department's online map at sfplanning.org/zoning-map. Enter your address to find your parcel's zone designation, height/bulk district, and any overlay districts. You can also look up whether your property is in a historic district or on the list of individually designated landmarks.
Source: San Francisco Building Code — ADU (Accessory Dwelling Unit) Requirements. Last verified April 5, 2026. View source