Do I Need a Permit to Build an ADU in San Francisco, CA?

ADU-specific overview

What makes this different from a simple accessory structure

Pulled from the city's ADU guidance and linked code references.

Permit type: Dual-agency process: SF Planning Department ADU Screening (or Waiver or CUA) followed by DBI building permit. Planning clearance is required before DBI will issue the permit. Entry point is the Planning ADU Screening form at sfplanning.org.
Maximum size: California state law requires local rules to allow new detached ADUs up to 1,200 sq ft and attached ADUs of at least 850 sq ft (or 1,000 sq ft for 2+ bedrooms). SF Planning Code Section 207 sets local maximums for non-state-law tracks; ministerial state-law ADUs follow the state size floors. JADUs are capped at 500 sq ft within existing living area.
Setbacks: State ADU law limits side and rear setbacks for newly constructed ADUs to no more than 4 feet. ADUs or JADUs created entirely within existing building envelope require no new setbacks. Hillside and slope protection regulations (Planning Code Article 7) may impose additional constraints on detached ADUs on steep lots.
Owner occupancy: California state law prohibits local agencies from imposing owner-occupancy requirements on ADUs through at least January 1, 2025 (extended by AB 976 through 2030). JADUs retain an owner-occupancy requirement under state law unless an affordable-housing deed restriction applies. SF Planning Code Section 207 conforms to the state law prohibition for ADUs.
Parking: Replacement parking is not required when an existing garage or covered space is converted to build an ADU. New parking is not required for an ADU within one-half mile of public transit or in a zone where parking is not required for the primary dwelling. Most San Francisco parcels are within one-half mile of transit.
Utilities: Habitable ADUs require separate electrical, plumbing, and mechanical systems meeting the SF Building Code and California codes. New utility service connections may require coordination with PG&E (electric/gas) and SFPUC (water/sewer). DBI trade permits are required for all MEP work.
JADU distinction: A Junior ADU (JADU) must be created within the existing living area of a single-family dwelling and is capped at 500 sq ft. It must have a cooking facility but may share a bathroom with the primary dwelling. State law requires owner occupancy in the primary or junior unit unless an affordable-housing deed restriction applies.

SF Planning Department ADU Screening is the mandatory first step — do not go to DBI first. DBI will not accept an ADU building permit application without a Planning determination.
The SF Administrative Waiver Program (Planning Code Section 207) offers a faster, less expensive path than a Conditional Use Authorization hearing for qualifying existing-building ADU projects.
San Francisco's Rent Ordinance (Administrative Code Chapter 37) imposes significant compliance obligations on ADU projects in rental buildings with 5+ units built before June 13, 1979 — a requirement unique among California cities of comparable size.
New detached ADUs on slopes exceeding 20% and in the Slope Protection Area may require additional Planning review and a geotechnical report.

Conditions

Full permit conditions

All 8 conditions for San Francisco adu permits.

All ADUs in San Francisco require a building permit issued by the Department of Building Inspection (DBI). Most ADU projects also require a Planning Department determination before DBI will issue the permit — starting with the Planning Department's ADU Screening process is the required first step.
San Francisco regulates ADUs under Planning Code Section 207. The code creates multiple authorization tracks: (1) a ministerial state-law ADU track for projects meeting California AB 68, AB 881, AB 2221, and SB 9 standards; (2) the San Francisco Administrative Waiver Program for qualifying existing buildings; and (3) a Conditional Use Authorization hearing for ADUs that exceed state-law or local size limits or are subject to discretionary review.
The SF Waiver Program allows eligible property owners to add ADUs in certain residential buildings through an administrative waiver rather than a full Planning hearing. To qualify, the project must meet Planning Code Section 207's waiver criteria, including size, setback, and building-type conditions. The waiver process is faster and less expensive than a full Conditional Use Authorization.
California state ADU law (SB 9, AB 68, AB 881, AB 2221) has preempted many local restrictions. New construction detached ADUs up to 1,200 square feet must be permitted ministerially (no discretionary hearing) if they meet setback and zoning requirements. State law limits side and rear setbacks for ADUs to no more than 4 feet for newly constructed units.
San Francisco's Rent Ordinance (Administrative Code Chapter 37) creates an important caveat for ADU construction in rental buildings: any ADU in a building with 5 or more units that was built before June 13, 1979 is subject to Rent Board notification, tenant-protection, and potential relocation-assistance requirements. This is a significant compliance layer that applies in SF but not most other California cities.
Junior ADUs (JADUs) — up to 500 square feet created within an existing single-family dwelling's living area — are permitted ministerially in SF under state law. A JADU does not require a separate entrance from the exterior but must have a cooking facility. The owner must occupy either the JADU or the primary dwelling unless an affordable-housing deed restriction applies.
Parking replacement is not required when an existing garage or covered parking space is converted to create an ADU, and new parking is not required for an ADU if the parcel is within one-half mile of transit or in a residential zone where parking is not required for the primary dwelling.
San Francisco's hilly terrain, lot irregularities, and hillside building regulations (Planning Code Article 7) may require additional structural engineering and Planning review for ADUs on steep lots or in Slope Protection Areas.

Fees

Estimated city fees

Baseline for a simple permitted adu: $3,000–$12,000+ is a realistic combined planning, building permit, and trade permit range for a typical San Francisco ADU; Rent Ordinance costs are additional and project-specific

Fee	Amount	Notes
Planning Department ADU Screening / Waiver fee	$250–$1,500 (estimated, depending on track)	The ADU Screening determination is the first Planning gate. Administrative waiver applications carry a lower fee than a full Conditional Use Authorization hearing. Verify current amounts at sfplanning.org before submitting.
DBI building permit fee	$1,500–$8,000+ (estimated, valuation-based)	DBI building permit fees are based on construction valuation under the San Francisco Building Code fee schedule. New detached ADUs and large interior conversions price significantly higher than simple accessory structure work. Verify the current fee schedule at dbi.sfgov.org.
Trade permits (electrical, plumbing, mechanical)	$300–$1,500+ each depending on scope	Habitable ADUs require separate electrical, plumbing, and mechanical permits issued by DBI in addition to the main building permit.
State SMIP surcharge	0.013% of project valuation	California Strong Motion Instrumentation Program surcharge applies statewide to all building permits.
Rent Board notification costs (5+ unit buildings built before 1979)	Variable — consult a local attorney	Buildings subject to the SF Rent Ordinance require Rent Board notification and may require relocation assistance payments to displaced tenants. These are not DBI or Planning fees — they are legal obligations under Administrative Code Chapter 37.

Documents

Required documents

Planning Department ADU Screening application submitted online via the SF Planning online portal (sfplanning.org). This is the required entry point to determine which authorization track applies to your project.
Site plan showing the lot, existing buildings, proposed ADU location, setbacks from property lines, and any existing covered parking.
Architectural floor plans, elevations, and cross-sections showing ADU dimensions, ceiling heights, egress windows, kitchen/bath layout, and exterior design.
Structural drawings conforming to the San Francisco Building Code and California Building Code (CBC) seismic requirements. San Francisco is in Seismic Design Category D; hold-down hardware, moment frames, or shear walls are typically required for new detached ADUs and additions.
Geotechnical or soils report for new detached ADU foundations on steep lots, hillside sites, or lots with liquefaction or landslide risk as identified in the SF Planning Department's Seismic Hazard Zones.
Title 24 energy compliance documentation (CAlCERTS or similar software report) for new construction or significant alterations that trigger Title 24 Part 6 (Energy).
Rent Board notification documentation if the property is subject to the SF Rent Ordinance (residential buildings with 2 or more units constructed before June 13, 1979). Consult the SF Rent Board at sfrb.org for current requirements.
For SF Waiver Program applications: the Planning ADU Waiver application and supporting compliance documentation showing the project meets Section 207 waiver eligibility criteria.
For state-law ministerial ADUs: documentation confirming the project meets California ADU law size, setback, and eligibility standards.

Timeline

Typical timing

Plan review: 15–45 business days for standard DBI residential plan review; ministerial state-law ADU track may qualify for a 60-day statutory deadline under California Government Code § 65852.2
Total cycle: 6–18 months for most San Francisco ADUs from initial Planning screening through final inspection

SF ADU timelines vary significantly by track. Ministerial state-law ADUs have a statutory 60-day approval deadline, but DBI workload and correction rounds extend construction timelines. Projects requiring Conditional Use Authorization hearings or Rent Ordinance compliance add months to the front end.

Process

How the permit process works

Determine which ADU track applies Start with the SF Planning Department's ADU Screening process (sfplanning.org/resource/accessory-dwelling-units). Planning will determine whether your project qualifies for ministerial state-law approval, the SF Administrative Waiver Program, or requires a Conditional Use Authorization hearing. Submit the ADU Screening application before preparing a full permit package.
Check Rent Ordinance obligations If the property is a residential building with 2 or more rental units built before June 13, 1979, review your obligations under SF Administrative Code Chapter 37 before proceeding. Buildings with 5 or more such units require Rent Board notification of the ADU project. Relocation assistance may be required if an existing tenant is temporarily or permanently displaced. Consult the SF Rent Board (sfrb.org) or a local attorney early.
Submit Planning ADU Screening or Waiver application File the ADU Screening application with the SF Planning Department via the online portal. If the project qualifies for the Administrative Waiver Program (Planning Code Section 207), submit the waiver application. Planning will issue a screening determination or waiver approval that authorizes you to proceed to DBI for the building permit.
Prepare seismic-compliant plans with a licensed professional Hire a licensed architect and structural engineer to prepare permit drawings. San Francisco is in Seismic Design Category D — structural details including hold-downs, shear walls, and proper foundation anchorage are required. On hillside lots, a geotechnical investigation may be needed. Plans must comply with the 2022 California Building Code and SF Building Code amendments.
Submit DBI building permit application File the building permit application through DBI's Permit Center (1660 Mission St.) or the online permit portal (dbi.sfgov.org). Include the Planning screening determination or waiver approval with the submittal. DBI plan review covers structural, life-safety, energy, and accessibility code compliance.
Respond to plan check corrections and pay fees DBI plan checkers will issue correction letters if revisions are required. Respond to all corrections and resubmit through the permit portal. Once plan check is cleared, pay the DBI permit fees and any outstanding Planning fees. Pull trade permits (electrical, plumbing, mechanical) concurrently.
Build and pass inspections Schedule required DBI inspections — foundation, framing, rough mechanical/electrical/plumbing, and final. CalGreen inspections are bundled into the DBI inspection sequence. San Francisco's terrain and party-wall density can complicate access and sequencing — coordinate with neighbors early on detached ADUs.
Close the permit and obtain certificate of final completion After final inspection sign-off, DBI issues a Certificate of Final Completion. This document is the legal proof that the ADU is a permitted dwelling unit. San Francisco requires disclosure of unpermitted construction under California Civil Code § 1102; the Certificate of Final Completion is essential for title insurance, financing, and future resale.

Code basis

What San Francisco reviews against

San Francisco Planning Code Section 207, San Francisco Building Code (2022 CBC with SF amendments), California ADU law (AB 68 / AB 881 / AB 2221 / SB 9), and SF Administrative Code Chapter 37 (Rent Ordinance) where applicable.

Residential permit page San Francisco permit portal

If you skip the permit

What can go wrong

DBI can issue a Notice of Violation (NOV) and stop-work order for unpermitted dwelling unit construction at any stage. SF NOVs are public record and affect property title.
After-the-fact ADU permits in San Francisco require invasive inspections and retroactive compliance with current code, often at far greater cost than the original permit would have been.
Unpermitted ADUs in rental buildings subject to the Rent Ordinance create additional legal exposure: the Rent Board and tenants can challenge occupancy and rent collection for units without final permits.
California Civil Code § 1102 requires disclosure of known unpermitted construction in real estate transactions. An unpermitted ADU must be disclosed to buyers and is typically flagged by title insurers.
Seismic and structural deficiencies in an uninspected ADU — undersized shear walls, inadequate hold-downs, poorly anchored foundations on steep lots — go undetected and pose genuine life-safety risk in earthquake country.
Unpermitted work can void homeowner's insurance coverage for the structure and for liability associated with tenant occupancy.

FAQ

Common San Francisco adu permit questions

Do I need a permit to build an ADU in San Francisco, CA?

Yes. All ADUs in San Francisco require a building permit from DBI. Most projects also require a Planning Department ADU Screening determination first — the Planning screening is the mandatory entry point, not DBI. Submit the ADU Screening application at sfplanning.org before preparing a full permit package.

What is the SF ADU Screening form and why do I need it?

The SF Planning Department's ADU Screening process determines which authorization track applies to your project: ministerial state-law approval, the SF Administrative Waiver Program, or a full Conditional Use Authorization hearing. DBI will not accept an ADU building permit application without a Planning determination. Starting with Screening saves time and avoids rejected DBI submittals.

What is the SF ADU Waiver Program?

The San Francisco Administrative Waiver Program, codified in Planning Code Section 207, allows qualifying ADU projects in existing residential buildings to obtain Planning approval through an administrative waiver rather than a full discretionary Conditional Use Authorization hearing. The waiver is faster, less expensive, and avoids a public hearing. Eligibility depends on building type, proposed ADU size, and compliance with Section 207 waiver criteria.

How does the SF Rent Ordinance affect ADU construction?

San Francisco's Rent Ordinance (Administrative Code Chapter 37) protects tenants in buildings with 2 or more units built before June 13, 1979. For buildings with 5 or more such units, the property owner must notify the Rent Board of the ADU project. If any tenant is temporarily or permanently displaced during construction, relocation assistance may be required. This compliance layer is unique to San Francisco and adds cost and time that many homeowners don't anticipate.

Does California's ADU preemption law apply in San Francisco?

Yes. California ADU law (AB 68, AB 881, AB 2221, SB 9) preempts local restrictions that exceed state standards. Ministerial ADUs meeting state size, setback, and eligibility criteria must be approved within 60 days under California Government Code § 65852.2. San Francisco's Planning Code Section 207 conforms to state law for these ministerial tracks, even though the city retains the dual-agency Planning + DBI process.

Does San Francisco require owner occupancy for an ADU?

No, not for full ADUs. California state law prohibits local agencies from imposing owner-occupancy requirements on ADUs through at least 2030 (AB 976). Junior ADUs (JADUs) retain an owner-occupancy requirement under state law — the owner must occupy either the JADU or the primary dwelling — unless an affordable-housing deed restriction applies.

How long does an SF ADU permit take?

San Francisco ADU timelines vary widely. Ministerial state-law ADUs have a 60-day statutory Planning review deadline, but DBI plan review, correction rounds, and construction inspections add months. Most SF ADU projects take 6–18 months from initial Planning Screening through final DBI inspection. Projects requiring Conditional Use Authorization hearings or Rent Ordinance compliance take longer.

Do I need solar panels on a new detached ADU in San Francisco?

Yes, for new detached ADUs constructed from scratch. California's Title 24 Part 6 (2022 Building Energy Efficiency Standards) requires newly constructed residential dwelling units, including detached ADUs, to include solar photovoltaic systems meeting minimum sizing requirements. The solar requirement does not apply to ADUs created through garage conversions or interior conversions of existing space.

Sources

Official links and freshness

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