ADU Permit Guide for San Francisco, California — Step-by-Step Process (2026)

Before you submit any application, you need to prove you own the property and that it contains a legal existing dwelling. Get your property deed and title report from your title company or attorney. San Francisco requires the main house to be legally habitable and permitted before you can add an ADU.

Your property must be zoned for residential use. San Francisco allows ADUs in RH-1 (single-family), RH-2 (two-family), and RH-3 (three-family) zones. Verify your zoning using the San Francisco Planning Department's Property Information Map /search. Enter your address and look for the "Zoning District" field.

Properties in certain historic districts face additional restrictions. If your property sits in the Alamo Square Historic District, Castro Street Historic District, or other designated areas, expect longer review times and stricter design requirements. Check the Planning Department's Historic Preservation page to see if your address falls within any historic boundaries.

Several conditions disqualify properties entirely. You cannot build an ADU if your lot is smaller than the minimum required for your zone (typically 2,500 square feet in RH-1 areas), if you're in a flood zone without proper mitigation, or if existing violations remain open on the property. Outstanding permits or code violations must be resolved before ADU approval.

Order a title report to identify any deed restrictions, easements, or covenants that might prohibit ADUs. Some neighborhoods have CC&Rs (Covenants, Conditions & Restrictions) that ban rental units entirely. Review these documents carefully – the city won't check these private restrictions for you.

The San Francisco Planning Department requires proof of utility capacity for water, sewer, and electrical service. Contact PG&E and the San Francisco Public Utilities Commission early to verify your property can handle additional connections. Properties with shared meters often need expensive upgrades before ADU approval.

Start with the San Francisco Planning Department's ADU webpage to download the current ADU packet. This packet contains zone-specific setback requirements, height limits, and size restrictions. In RH-1 zones, ADUs cannot exceed 1,200 square feet or 75% of the existing dwelling size, whichever is smaller. RH-2 and RH-3 zones allow slightly more flexibility.

Setback requirements vary by zone and ADU type. Detached ADUs in RH-1 zones need 4-foot rear setbacks and 3-foot side setbacks. Attached ADUs can use existing building setbacks. Measure your property boundaries carefully using the property survey from your title report. The city's online setback calculator /tools/setback-calculator helps verify compliance, but double-check measurements manually.

San Francisco offers pre-application conferences for $400. Schedule these through the Planning Department counter at 49 South Van Ness Avenue. Bring a site plan showing your proposed ADU location, existing structures, and property lines. The planner reviews setbacks, height limits, and potential issues in a 30-minute meeting. This investment prevents expensive design mistakes later.

Check utility capacity early. San Francisco requires separate water and sewer connections for most ADUs. The Public Utilities Commission charges $5,200 for new water connections and $6,800 for sewer connections. Properties on combined systems may need expensive separations costing $15,000-$25,000. Request utility capacity letters from SFPUC and PG&E before hiring an architect.

Research parking requirements for your specific address. Most areas require one parking space per ADU unit, but properties within one-quarter mile of public transit may qualify for exemptions. The Planning Department's transit proximity map shows qualifying areas. Bike parking can sometimes substitute for car parking in transit-rich neighborhoods.

Review your property for protected trees. San Francisco's Urban Forestry ordinance protects trees over 12 inches in diameter. Removing or significantly pruning protected trees requires separate permits costing $500-$2,000 and adds 4-6 weeks to your timeline. The Department of Public Works maintains a street tree map showing city-owned trees that cannot be removed.

San Francisco requires complete architectural plans for all ADU applications. Your plan set must include a site plan, floor plans, building elevations, structural calculations, and Title 24{:target="_blank"} energy compliance forms. No pre-approved plan program exists in San Francisco, so custom designs are mandatory.

The site plan shows your property boundaries, existing structures, proposed ADU location, setbacks, and utility connections. Include dimensions for all setbacks and clearly mark property lines. Show existing and proposed driveways, walkways, and parking spaces. The fire department requires 3-foot minimum access paths to ADU entrances.

Floor plans must show room layouts, dimensions, window and door locations, and fixture placements. Include ceiling heights (minimum 7.5 feet for habitable rooms), egress window specifications, and bathroom ventilation. San Francisco requires natural light in all habitable rooms – show window sizes and locations clearly.

Building elevations show the ADU from all four sides with height dimensions, materials, colors, and architectural details. Match existing house materials and colors when possible. The Planning Department scrutinizes design compatibility in historic districts. Include manufacturer specifications for windows, doors, and roofing materials.

Structural calculations require a California licensed engineer's stamp. The engineer must account for San Francisco's seismic requirements and soil conditions. Expect to pay $3,000-$5,000 for structural engineering on detached ADUs. Foundation plans must show rebar spacing, concrete specifications, and connection details.

Title 24 energy compliance forms document insulation values, window specifications, and HVAC efficiency. California requires these forms for all new construction. A certified energy consultant prepares these documents for $800-$1,200. Include lighting fixture schedules and appliance efficiency ratings.

Electrical and plumbing plans show circuit layouts, panel locations, fixture placements, and connection points. Licensed contractors typically prepare these plans during the application process. Show emergency shutoff locations and smoke detector placements clearly.

Hire architects familiar with San Francisco's ADU process. Expect to pay $8,000-$15,000 for complete plan preparation. Architects experienced with SF Planning Department requirements produce cleaner plan sets that pass review faster.

San Francisco accepts ADU applications through the Planning Department at 49 South Van Ness Avenue, Suite 1400. No online submission system exists yet. Applications are accepted Monday through Friday, 8:00 AM to 5:00 PM. Arrive early – the counter gets busy after 10:00 AM.

Bring your complete application packet including the Building Permit Application (form DBI-03), Planning Department ADU checklist, architectural plans (3 sets), structural calculations, Title 24{:target="_blank"} forms, property survey, and utility capacity letters. Plans must be folded to 8.5" x 14" or provided on a USB drive in PDF format.

Application fees break down as follows: Building permit application fee ($500), Planning Department review fee ($2,300), Fire Department review fee ($800), and Public Works review fee ($400). School impact fees cost $4.79 per square foot for units over 750 square feet. A 1,000-square-foot ADU pays approximately $1,197.50 in school fees.

Impact fees are waived for ADUs under 750 square feet per SB 13. Larger units pay partial impact fees calculated on a sliding scale. The Planning Department's fee calculator determines exact amounts based on square footage and location.

Complete the Building Permit Application carefully. List the project as "Construction of Accessory Dwelling Unit" in the project description. Include accurate square footage and construction value estimates. Use $300 per square foot for construction valuation – the city calculates permit fees from this number.

The property owner must sign all applications. If you're working with a contractor or architect, they can be listed as the applicant's representative but cannot sign legal documents. Bring original identification matching the property deed.

The Planning Department assigns a case number immediately and provides a receipt with estimated review timeline. Initial review takes 30-45 days for completeness check. Complete applications enter the formal 60-day review clock mandated by state law.

Common submission mistakes include incomplete utility letters, missing structural engineer stamps, and incorrectly scaled drawings. Double-check plan dimensions and ensure all sheets include the project address and north arrow.

After submission, your application moves through four department reviews: Planning, Building, Fire, and Public Works. The Planning Department coordinates the review process and provides a single point of contact. Each department has 60 days total to approve or request corrections per AB 68{:target="_blank"} requirements.

The Planning Department reviews zoning compliance, setbacks, height limits, and design compatibility. Planning review focuses on objective standards rather than subjective design preferences. Reviewers check setback dimensions, building coverage calculations, and parking compliance.

Building Department review covers structural safety, accessibility compliance, and building code conformance. Building plan checkers examine foundation details, framing connections, electrical capacity, and fire safety requirements. California Building Code{:target="_blank"} and San Francisco Building Code amendments both apply.

The Fire Department reviews emergency egress, fire separation distances, and access for emergency vehicles. ADUs need direct exterior access and proper egress windows in bedrooms. Fire separation requirements between main house and detached ADUs depend on distance – structures closer than 6 feet need one-hour fire ratings.

Public Works reviews utility connections, stormwater management, and sidewalk impacts. New water and sewer connections require separate permits from SFPUC. Properties with existing shared utilities often need expensive upgrades to city standards.

Plan check comments arrive via email or mail within 45-60 days. Comments list specific deficiencies requiring correction before approval. Common comments include setback adjustments, structural detail clarifications, and utility capacity documentation.

Respond to comments quickly to maintain review momentum. Submit revised plans within 90 days or the application expires. Minor corrections can be submitted as plan revisions – major changes require new applications. Work closely with your architect to address comments thoroughly.

Expect 1-2 rounds of corrections for well-prepared applications. Complex projects or incomplete initial submissions may require 3-4 correction cycles. Each revision round adds 15-30 days to the approval timeline.

Once permits are issued, construction can begin immediately. San Francisco requires permit placards posted visibly on the job site. Building permits expire after 180 days if construction hasn't started, so break ground promptly.

Schedule inspections through the Department of Building Inspection's automated system at (628) 652-3200 or online portal. Request inspections by 3:00 PM for next-day appointments. Inspectors typically arrive between 8:00 AM and 4:00 PM on scheduled days.

Foundation inspection occurs after excavation and rebar placement but before concrete pour. The inspector verifies foundation depth, rebar size and spacing, and anchor bolt locations. Schedule this inspection 24-48 hours before your concrete pour date.

Rough framing inspection happens after framing completion but before insulation installation. Inspectors check structural member sizes, connection hardware, and earthquake bracing. Electrical and plumbing rough-ins often combine with framing inspection.

Electrical rough inspection covers wiring installation, panel connections, and outlet box placement. Schedule after wiring is complete but before drywall installation. Electrical inspectors check proper circuit sizing, GFCI protection, and smoke detector wiring.

Plumbing rough inspection verifies pipe sizing, connection methods, and fixture locations. Include gas line inspections if installing gas appliances. Water pressure testing may be required before covering pipes with drywall.

Insulation and drywall inspection ensures energy code compliance and fire safety. Bring Title 24{:target="_blank"} compliance documents showing insulation R-values. This inspection occurs after insulation but before drywall finishing.

Final inspection covers all completed work including fixtures, appliances, smoke detectors, and egress windows. The inspector verifies the ADU matches approved plans and meets all code requirements. Address numbers must be posted and utilities connected.

Failed inspections require corrections before re-inspection. Common failures include missing smoke detectors, improper egress windows, and incomplete electrical connections. Re-inspection fees cost $150 per visit after the first failure.

After passing final inspection, request a Certificate of Occupancy through the Department of Building Inspection. This certificate confirms the ADU meets all safety codes and can be legally occupied. Processing takes 5-10 business days after final inspection approval.

The Certificate of Occupancy includes the official address assignment for your ADU. San Francisco assigns addresses based on street access and unit configuration. Attached ADUs typically receive unit numbers (e.g., 123 Main Street, Unit B), while detached ADUs may get separate street addresses.

Submit address assignment requests during the permit process to expedite occupancy approval. The Department of Public Works coordinates with emergency services to ensure proper address identification. Clear address marking is required before occupancy approval.

Utility connections must be completed before occupancy. Contact PG&E to establish separate electrical service if required. SFPUC handles water and sewer connections based on approved permit plans. Gas service requires separate applications and inspections.

The completed ADU must be recorded with the San Francisco County Assessor within 30 days of occupancy approval. This creates official records for property tax assessment and legal documentation. The ADU becomes part of your property's legal description.

Property taxes increase based on the ADU's assessed value. The County Assessor typically values ADUs at $200-$300 per square foot for tax purposes. A 1,000-square-foot ADU might add $50,000-$75,000 to assessed value, increasing annual property taxes by $500-$750.

You can legally rent the ADU immediately after receiving the Certificate of Occupancy. No owner-occupancy requirements exist for ADUs permitted before 2025 per state law. Rental income is subject to San Francisco rent control ordinances for units built before 1978.

Register your rental unit with the San Francisco Rent Board if the ADU falls under rent control. Registration costs $40 annually and establishes legal rental status. Maintain copies of all permits and certificates for future tenants and property sales.

Setback violations represent the most frequent denial reason in San Francisco. Many applicants misinterpret property boundaries or ignore easement restrictions. Bay windows, eaves, and architectural projections can trigger setback violations even when the main structure complies. Always hire a licensed surveyor to verify property lines before design. Use the city's official setback calculator /tools/setback-calculator and add 6-inch buffers for construction tolerance.

Incomplete or inaccurate architectural plans cause significant delays. Missing structural details, unmarked dimensions, and inconsistent floor plans trigger automatic rejections. The Planning Department requires plans stamped by California-licensed professionals. Plans must show all existing structures, utility connections, and grade changes. Hiring experienced local architects familiar with San Francisco requirements prevents most plan-related delays.

Utility capacity issues stop many projects completely. Older properties often lack adequate electrical service for additional units. Water and sewer systems may need expensive upgrades to handle ADU connections. The SF Public Utilities Commission requires separate connections for most ADUs, costing $12,000-$18,000 for combined water/sewer hookups. Order utility capacity studies before architectural design to avoid costly redesigns.

Historic district restrictions add layers of complexity in designated neighborhoods. Properties in Alamo Square, Castro Street, or other historic districts face stricter design review. Window styles, roofing materials, and building heights must match historical character. The Historic Preservation Commission reviews ADUs in sensitive areas, adding 30-45 days to approval timelines. Research historic designation status early using the Planning Department's historic resource maps.

Homeowners Association conflicts create legal obstacles the city cannot resolve. Many HOA CC&Rs prohibit rental units or accessory structures entirely. Review HOA documents thoroughly before spending money on plans. Some associations require architectural committee approval separate from city permits. Factor HOA review time into project schedules – some committees meet quarterly, adding months to timelines.

Fire access requirements frequently trigger design changes. ADUs need clear emergency vehicle access and proper fire separation from main structures. Detached ADUs closer than 6 feet to existing buildings require expensive one-hour fire-rated construction. Narrow lots may not accommodate required access paths. The Fire Department reviews emergency access routes and water supply adequacy during plan review.

Tree preservation ordinances protect mature trees throughout San Francisco. Removing trees over 12 inches diameter requires separate permits and tree replacement fees up to $1,800 per tree. Construction near existing trees may require root protection zones and specialized foundation designs. The Department of Public Works maintains protected tree inventories – check these maps before site planning. Arborist reports cost $800-$1,200 but prevent expensive delays from tree conflicts.

To avoid these common problems, invest in professional pre-application research. Spend $2,000-$3,000 on surveys, utility studies, and historic research before architectural design. This upfront cost prevents $10,000+ redesign expenses later. Work with local professionals familiar with San Francisco's specific requirements and current code interpretations.