About San Francisco
Known for its vibrant culture and diverse community, San Francisco is a prominent city in California, featuring beautiful landscapes, innovative industries, and rich history.
San Francisco ADU Regulations
California State ADU Laws
California has some of the most progressive ADU legislation in the country. Recent laws including AB 68, SB 13, and AB 881 have significantly streamlined the ADU approval process and reduced barriers for homeowners.
Key California ADU Regulations:
- Size Limits: Detached ADUs can be up to 1,200 sq ft. Attached ADUs can be up to 50% of the primary dwelling or 1,200 sq ft, whichever is less.
- Setbacks: Minimum 4-foot side and rear setbacks for detached ADUs.
- Height: Generally up to 16 feet, with some exceptions for two-story ADUs (up to 25 feet in certain zones).
- Parking: No additional parking required in most cases, especially near transit.
- Owner Occupancy: No owner-occupancy requirement until 2025 for most ADUs.
San Francisco Local Requirements
While California state law provides baseline regulations, San Francisco may have additional local requirements. GatherADU's team stays current with San Francisco's specific zoning codes, architectural guidelines, and permit processes to ensure your ADU project meets all requirements.
Common local considerations in San Francisco include:
- Design review requirements and architectural standards
- Utility connection fees and impact fees
- Fire department access requirements
- Neighborhood-specific overlay zones
Your Rights Under California Law
This information is for informational purposes only and does not constitute legal advice. Consult a qualified attorney for legal guidance.
California law (AB 68, AB 881, SB 9, and subsequent legislation) guarantees your right to build ADUs. Cities cannot:
- Require owner-occupancy for ADUs permitted after 2020
- Require additional parking for ADUs near transit
- Charge impact fees for ADUs under 750 sq ft
- Deny ADUs that meet state minimum standards
- Impose lot coverage limits that prevent a 800 sq ft ADU
If you believe your ADU application is being unfairly denied, California HCD can intervene on your behalf.
California State ADU Rules
California ADU Legislation Overview
California leads the nation in ADU-friendly legislation. The state has passed numerous laws to encourage ADU construction as a solution to the housing crisis.
Key California ADU Laws:
- AB 68 (2020): Reduced local government review time and expanded ADU construction options.
- SB 13 (2020): Limited impact fees and reduced owner-occupancy requirements.
- AB 881 (2020): Prohibited minimum lot size requirements and allowed JADUs in all zones.
- AB 2221 (2022): Further streamlined the ADU approval process.
- SB 897 (2022): Increased height limits for ADUs in certain zones.
California ADU Benefits:
- Property value increase of 20-30% on average
- Rental income potential of $1,500-$3,500+ monthly
- Housing flexibility for family members
- No owner-occupancy requirements (until 2025)
More About San Francisco
San Francisco, often simply called SF or "the City by the Bay," is a cultural, commercial, and financial powerhouse of the West Coast. Known for its iconic Golden Gate Bridge, steep rolling hills, eclectic Victorian architecture, and foggy summers, San Francisco offers a unique blend of natural beauty and urban sophistication.
Population: With approximately 815,000 residents, San Francisco is relatively small in area but densely populated. The larger Bay Area, including cities like Oakland and San Jose, has a population about 883305, making it one of the most significant metropolitan areas in the United States.
Local Economy: San Francisco's economy is primarily driven by the tech industry, with Silicon Valley just to the south. The city is home to numerous tech giants and startups, making it a global center for innovation. Besides technology, San Francisco's economy is bolstered by finance, tourism, and professional services. The city hosts the headquarters of five major banking institutions and various multinational companies. Its port, although not as large as Los Angeles', still plays a crucial role in international trade.
Popular Neighborhoods:
- North Beach: Known as Little Italy, famous for its Italian heritage and beatnik history.
- The Mission: A vibrant, multicultural area known for its Latino roots and hipster vibe.
- Haight-Ashbury: The epicenter of 1960s counterculture, now a bohemian shopping district.
- Nob Hill: An affluent neighborhood known for its luxury hotels and stunning city views.
- SoMa (South of Market): A former industrial area now home to many of the city's museums and tech startups.
- The Castro: The heart of San Francisco's LGBTQ+ community, known for its vibrant nightlife.
Real Estate Overview: San Francisco consistently ranks as one of the most expensive real estate markets in the United States. The median home price hovers around $1.3 million, significantly higher than the national average. The rental market is equally competitive, with average rents far exceeding those in most other U.S. cities. The high costs are driven by limited supply, strict zoning laws, and the city's desirability among high-earning tech workers.
Landmarks and Attractions:
- Golden Gate Bridge: The city's most famous landmark, an engineering marvel and icon of American design.
- Alcatraz Island: Former high-security prison turned national park and popular tourist destination.
- Fisherman's Wharf: Waterfront neighborhood known for seafood restaurants and sea lion sightings.
- Chinatown: The largest Chinatown outside of Asia and the oldest in North America.
- Cable Cars: The world's last manually operated cable car system, now primarily a tourist attraction.
- Painted Ladies: Row of colorful Victorian houses, often featured in postcards and TV shows.
ADU Regulations in San Francisco:
San Francisco has embraced ADUs as a solution to its housing crisis, implementing regulations to encourage their construction:
- Zoning: ADUs are permitted citywide in areas zoned for residential use.
- Size Limits: There's no maximum size limit for ADUs, but they must fit within the buildable area of the lot and comply with relevant Planning Code requirements.
- Parking: No parking is required for ADUs. In fact, the ADU program allows for the removal of required parking to add an ADU.
- Owner Occupancy: As of 2020, there's no owner-occupancy requirement for either the primary residence or the ADU.
- Number of ADUs: Single-family homes can add one ADU. Multi-family buildings can add unlimited ADUs within existing habitable space and up to two detached ADUs.
- Rent Control: ADUs in buildings constructed before June 13, 1979, are subject to the city's rent control ordinance.
- Streamlined Process: San Francisco offers a streamlined approval process for certain types of ADUs, particularly those within the existing building envelope.
These progressive regulations have led to a significant increase in ADU applications and approvals in recent years.
Unique Aspects of San Francisco:
San Francisco's charm lies in its ability to pack diverse experiences into a compact area. The city's 49 square miles contain a patchwork of distinct neighborhoods, each with its own character and microclimate. It's often said that San Francisco is a city of microclimates, where the weather can change dramatically from one neighborhood to the next.
The city's commitment to progressivism and social justice is deeply ingrained in its culture. From the Summer of Love in the 1960s to its leadership in LGBTQ+ rights, San Francisco has long been at the forefront of social movements. This progressive spirit extends to environmental policies, with the city aiming for zero waste and carbon neutrality.
San Francisco's food scene is world-renowned, offering everything from Michelin-starred restaurants to innovative food trucks. The city is credited with inventing or popularizing dishes like sourdough bread, cioppino, and the Mission-style burrito.
The tech industry's influence is palpable throughout the city. It's not uncommon to overhear discussions about startups and venture capital in local cafes. This has led to both rapid innovation and challenges, such as gentrification and income inequality, which the city continually grapples with.
Despite its urban density, San Francisco offers numerous opportunities for outdoor recreation. The city boasts over 220 parks, including the expansive Golden Gate Park. Nearby, outdoor enthusiasts can enjoy hiking in Muir Woods, wine tasting in Napa Valley, or skiing in Lake Tahoe, all within a few hours' drive.
Public transportation in San Francisco is more developed than in many U.S. cities, with its BART system connecting the city to the wider Bay Area. The city is also known for its commitment to alternative transportation, with extensive bike lanes and a growing network of electric vehicle charging stations.
In conclusion, San Francisco is a city of contrasts - a place where cutting-edge technology meets counterculture, where steep hills offer breathtaking vistas of the bay, and where fog-shrouded mornings give way to sun-drenched afternoons. Its progressive ADU regulations reflect the city's innovative spirit and commitment to addressing housing challenges, making San Francisco a unique urban experiment in one of the most beautiful settings in America.
Get Your Free San Francisco ADU Feasibility Report
Find out exactly what you can build on your property, estimated costs, and potential rental income.
Types of ADUs You Can Build in San Francisco
California law allows several types of accessory dwelling units on residential properties. Understanding your options helps you choose the best approach for your property and goals.
Detached ADU
A standalone structure built separately from your main house, typically in the backyard. Detached ADUs offer maximum privacy for both homeowners and tenants, with their own entrance, walls, roof, and complete living facilities. In San Francisco, detached ADUs can be up to 1,200 square feet and 16 feet tall. This option provides the most flexibility in design and placement, though it typically costs more than conversions due to new construction requirements.
- Max Size: Up to 1,200 sq ft
- Height: Up to 16 feet
- Setbacks: 4 ft from side/rear lines
- Best For: Maximum rental income, privacy
Attached ADU
An addition built onto your existing home, sharing at least one wall with the primary residence. Attached ADUs are often more cost-effective than detached units because they can leverage existing foundation, roof structure, and utility connections. They work well on properties with limited backyard space or where you want to minimize the visual impact of new construction. Many homeowners choose attached ADUs for aging parents who want proximity while maintaining independence.
- Max Size: Up to 1,200 sq ft
- Height: Matches main home
- Setbacks: Same as main structure
- Best For: Limited lot space, family housing
Garage Conversion ADU
Transform your existing garage into a complete living space. Garage conversions are often the most affordable ADU option in San Francisco because the basic structure already exists. You save on foundation, framing, and roofing costs while creating a valuable rental unit or family living space. California law prohibits cities from requiring replacement parking when you convert a garage to an ADU, making this option particularly accessible. Most garage conversions result in studios or one-bedroom units ranging from 400 to 600 square feet.
- Typical Size: 400-600 sq ft
- Timeline: 3-5 months typical
- Cost: 30-50% less than new construction
- Best For: Budget-conscious, quick timeline
Junior ADU (JADU)
A smaller unit of up to 500 square feet created within your existing home's footprint, typically by converting a bedroom, basement, or attached garage. JADUs must include a cooking facility (at minimum, a sink, counter, and small appliance outlet) but can share a bathroom with the main house. In San Francisco, you can build both a JADU and a full ADU on the same property, maximizing your housing options. JADUs require owner-occupancy in either the main house or the JADU itself.
- Max Size: 500 sq ft
- Location: Within existing home
- Requirements: Owner-occupancy required
- Best For: Minimal construction, family use
Above-Garage ADU
Build a new living unit above your existing or new garage structure. This two-story approach preserves your parking while adding living space above. In San Francisco, above-garage ADUs can reach 18-20 feet in height depending on distance from property lines. This option is particularly popular in neighborhoods with narrow lots where backyard space is limited. The elevated position often provides better views and natural light than ground-level units.
- Max Size: Up to 1,200 sq ft
- Height: Up to 18-20 feet
- Parking: Preserved below unit
- Best For: Limited lot space, maintaining parking
Basement Conversion
While less common in Southern California due to construction patterns, properties with existing basements can convert that space into an ADU. Basement conversions require proper egress windows, adequate ceiling height (at least 7 feet in habitable areas), and may need waterproofing and ventilation upgrades. When properly executed, basement ADUs provide naturally cool living space and complete separation from the main home's daily activities.
- Max Size: Existing footprint
- Requirements: Egress, ceiling height
- Benefits: Cool temps, full separation
- Best For: Existing basements only
Complete ADU Services in San Francisco
From initial feasibility analysis through final inspection, we handle every aspect of your ADU project. Our San Francisco-focused approach ensures your project meets all local requirements while maximizing value.
Feasibility Analysis
We begin every project with a comprehensive analysis of your property's ADU potential. Our team reviews your lot size, zoning, setbacks, utility connections, and neighborhood context to determine what you can build. In San Francisco, this includes understanding any overlay zones, historic district requirements, or other local factors that might affect your project. You receive a detailed report showing your options, estimated costs, and potential rental income before committing to design work.
- Property zoning verification
- Setback and lot coverage analysis
- Utility capacity assessment
- Cost and ROI projections
Design & Architecture
Our design team creates ADU plans tailored to your property and goals. Whether you want a modern studio for maximum rental income or a two-bedroom unit for family members, we design spaces that work. We understand San Francisco architectural context and create designs that complement existing homes while meeting all building code requirements. Every design includes structural engineering, Title 24 energy compliance, and all documentation needed for permits.
- Custom floor plan development
- 3D renderings and visualizations
- Structural engineering
- Energy compliance documentation
Permitting & Approvals
Navigating San Francisco permitting can be complex, but we handle it all. Our team prepares complete permit applications, manages plan check submissions, and coordinates with building department staff to address any comments or corrections. We track your application through the approval process and keep you informed of progress. Our experience with San Francisco regulations helps avoid common pitfalls that delay other projects.
- Complete permit application prep
- Plan check management
- Building department coordination
- Permit tracking and updates
Construction
Our licensed construction team builds your ADU with quality materials and skilled craftsmanship. We handle all aspects of construction including foundation, framing, electrical, plumbing, HVAC, insulation, drywall, flooring, cabinets, and finishes. Throughout the build, we coordinate required inspections, manage subcontractors, and keep you updated on progress. Our goal is delivering a finished ADU that exceeds your expectations while respecting your timeline and budget.
- Licensed general contractor
- Quality materials and finishes
- Inspection coordination
- Project management and updates
Interior Design
A well-designed interior maximizes both livability and rental appeal. Our interior design services help you select finishes, fixtures, and colors that create appealing spaces within your budget. We offer curated finish packages at different price points, or work with you to customize selections. From kitchen layouts that maximize counter space to bathroom designs that feel spacious, we sweat the details that make small homes work beautifully.
- Finish and fixture selection
- Space planning optimization
- Curated design packages
- Custom interior options
Financing Guidance
We help connect you with financing options suited to your situation. Many San Francisco homeowners use home equity, construction loans, or specialized ADU financing products to fund their projects. We can introduce you to lenders experienced in ADU financing and help you understand options including cash-out refinancing, HELOCs, and construction-to-permanent loans. While we're not lenders ourselves, our guidance helps you navigate financing decisions confidently.
- Financing option overview
- Lender introductions
- ROI and cash flow projections
- Budget planning assistance
How We Build Your San Francisco ADU
Our streamlined process takes you from initial concept to move-in ready ADU. Here's what to expect at each stage of your project.
Free Consultation
We start with a free consultation to understand your goals, assess your property, and explain your options. This can happen via phone, video call, or an in-person site visit in San Francisco. You'll learn what you can build, approximate costs, and timeline expectations. There's no obligation, just honest information to help you make a decision. If an ADU makes sense for your situation, we move forward with a detailed feasibility study.
Feasibility Study
Our team conducts a thorough analysis of your San Francisco property. We verify zoning, calculate setbacks and lot coverage, assess utility connections, and identify any site-specific considerations. You receive a written report with your ADU options, including size possibilities, placement locations, and preliminary cost estimates. This report becomes the foundation for design decisions.
Design Development
Working with our architects and designers, you'll develop floor plans, select exterior styles, and make finish selections. We create 3D renderings so you can visualize the finished ADU before construction begins. Once design is finalized, we complete structural engineering and Title 24 energy calculations. The result is a complete plan set ready for San Francisco permit submission.
Permitting
We submit your complete permit application to San Francisco and manage the entire approval process. This includes responding to plan check comments, coordinating with building department staff, and tracking your application through to permit issuance. California law requires cities to process compliant ADU applications within 60 days, though actual timelines vary. We keep you informed throughout and handle any issues that arise.
Construction
With permits in hand, construction begins. Our crews work efficiently while respecting your property and neighbors. For a typical San Francisco ADU, construction takes 4-6 months depending on size, complexity, and type. We coordinate all inspections, manage subcontractors, and provide regular progress updates. You'll have a dedicated project manager as your single point of contact throughout the build.
Final Walkthrough & Move-In
Before turning over the keys, we conduct a detailed walkthrough with you. We demonstrate systems and appliances, address any punch list items, and ensure everything meets your expectations. Once you're satisfied and final inspections are complete, you receive your certificate of occupancy. Your new San Francisco ADU is ready for occupancy, whether that means welcoming a tenant, moving in a family member, or whatever you have planned.
ADU Costs in San Francisco
Understanding ADU costs helps you plan realistically and evaluate the investment opportunity. Here's what to expect for typical San Francisco ADU projects.
Garage Conversion
$100,000 - $180,000Converting an existing garage is typically the most affordable path to an ADU. You save on foundation and framing since the basic structure exists. Costs vary based on garage condition, size, and finish level desired. Most garage conversions in San Francisco result in studios or one-bedroom units between 400-600 square feet.
- Electrical and plumbing installation
- HVAC system
- Insulation and drywall
- Kitchen and bathroom
- Flooring and finishes
- Permits and inspections
Detached New Construction
$200,000 - $400,000Building a new detached ADU involves complete construction from the ground up. This option costs more but offers maximum design flexibility and typically commands higher rents. A one-bedroom detached ADU in San Francisco typically costs $200,000-$280,000. Two-bedroom units range from $280,000-$400,000 depending on size and finishes.
- Foundation and site work
- Complete framing and roofing
- All mechanical systems
- Interior and exterior finishes
- Utility connections
- Design, engineering, permits
Attached Addition
$150,000 - $300,000Attached ADUs share a wall with your existing home, which can reduce some construction costs. You may be able to tie into existing roof structure and foundation, though this depends on your home's configuration. Costs fall between garage conversions and fully detached new construction for most San Francisco projects.
- Foundation extension (if needed)
- Framing and roofing integration
- Separate entrance and utilities
- Complete interior buildout
- Fire separation requirements
- Permits and inspections
Return on Investment
Actual rents depend on unit size, finishes, location within San Francisco, and current market conditions. One-bedroom ADUs typically rent higher than studios; two-bedroom units command premium rates.
According to Freddie Mac research, ADUs add 20-30% to property values in high-demand California markets. This often exceeds construction costs, creating immediate equity.
When you factor rental income against construction costs, many San Francisco ADUs generate 8-12% annual cash-on-cash returns, competitive with or exceeding other investment options.
Frequently Asked Questions About ADUs in San Francisco
Get answers to the most common questions about building an accessory dwelling unit in San Francisco.
How long does it take to get an ADU permit in San Francisco?
California law requires cities to approve compliant ADU permit applications within 60 days of submission. However, actual timelines in San Francisco depend on several factors including application completeness, plan check workload, and any corrections required. A well-prepared application with complete documentation typically moves faster than incomplete submissions. Including our design and engineering time, most homeowners should plan for 3-4 months from project start to permit issuance. We manage the entire process and keep you updated on timing.
Do I have to live on the property to build an ADU?
For ADUs permitted after January 1, 2020, California law prohibits cities from requiring owner-occupancy. This means you can rent out both your main house and your ADU if you choose, or live elsewhere entirely. The exception is Junior ADUs (JADUs), which do require the property owner to live in either the main house or the JADU. If you're considering a JADU, understand this requirement before proceeding. For standard ADUs in San Francisco, you have full flexibility in how you use the property.
Do I need to add parking for my ADU?
In most cases, no. California law exempts ADU parking requirements if your property is within half a mile of public transit, in a historic district, within one block of car-share pickup, or if on-street parking permits are required but not available to the ADU occupant. Additionally, if you convert a garage to an ADU, the city cannot require you to replace the lost parking. For properties that don't qualify for these exemptions, one parking space per ADU may be required, but it can be tandem, in setbacks, or through mechanical lifts. Most San Francisco properties near any bus route qualify for parking exemptions.
What's the maximum ADU size allowed in San Francisco?
California state law establishes a maximum ADU size of 1,200 square feet for units with more than one bedroom. Single-bedroom and studio ADUs have a minimum allowable size of 850 square feet under state law, though you can build smaller if you prefer. For attached ADUs that convert existing space within your home, the maximum is 50% of the primary dwelling's floor area or 1,200 square feet, whichever is greater. JADUs are limited to 500 square feet. In San Francisco, these state standards apply unless the city has adopted more generous local rules.
How much can I charge for rent on my San Francisco ADU?
ADU rents in San Francisco depend on unit size, finishes, location, and current market conditions. As a general guide, studios typically rent for $1,400-$2,200 monthly, one-bedroom units for $1,800-$2,800, and two-bedroom units for $2,400-$3,500 or more. Factors that command premium rents include private outdoor space, in-unit laundry, dedicated parking, modern finishes, and good natural light. We can provide more specific rental projections based on your property's location and the ADU type you're considering. These estimates help you evaluate the investment potential of your project.
How long does the entire ADU project take from start to finish?
A typical San Francisco ADU project takes 10-14 months from initial consultation to move-in ready. This breaks down roughly as: feasibility and design (2-3 months), permitting (2-3 months), and construction (4-8 months depending on project type and size). Garage conversions typically complete faster than new construction. Complex sites, custom designs, or unusually busy permitting periods can extend timelines. We provide realistic timeline estimates during our initial consultation based on your specific project scope and current conditions.
How do people finance ADU construction?
Most San Francisco homeowners use one of several financing approaches. Cash-out refinancing lets you tap existing home equity at favorable mortgage rates. Home equity lines of credit (HELOCs) provide flexible access to equity without refinancing your first mortgage. Construction loans provide funds specifically for building, converting to a permanent mortgage upon completion. Some lenders now offer ADU-specific loan products designed for these projects. The right choice depends on your current mortgage, available equity, and financial goals. We can connect you with lenders experienced in ADU financing to explore your options.
Will an ADU increase my property taxes?
Yes, adding an ADU will increase your property's assessed value and therefore your property taxes. However, under California's Proposition 13, only the new construction is reassessed, not your entire property. The increase is typically based on the cost of the ADU construction, not the full market value it adds. For example, a $200,000 ADU might add roughly $2,000-$2,500 annually in property taxes (at approximately 1.25% of assessed value). When compared to the rental income potential of $20,000-$40,000 annually, this tax increase is manageable and doesn't significantly impact overall returns.
Can my HOA prevent me from building an ADU?
California law (AB 670) prohibits HOAs from outright banning ADUs that conform to state law. However, HOAs can impose "reasonable" restrictions on ADU design elements like exterior colors, materials, and landscaping to maintain community aesthetics. They cannot unreasonably increase costs or delay your project. If you're in an HOA community in San Francisco, we recommend reviewing your CC&Rs and talking with your HOA board early in the process. We can help you navigate any architectural review requirements while ensuring your ADU meets both state requirements and community guidelines.
Does my ADU need separate utility meters?
Separate utility meters are not required by law, giving you flexibility in how to handle utilities. Options include: installing separate meters so tenants pay utilities directly; submetering so you can track and bill usage; or including utilities in rent. Each approach has trade-offs. Separate meters create the cleanest landlord-tenant relationship but cost more upfront. Including utilities is simpler but removes tenant incentive to conserve. Many San Francisco ADU owners choose submetering as a middle ground, maintaining one account while fairly allocating costs. We can discuss the pros and cons of each approach for your situation.
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