San Francisco, CA - ADU Regulations

Rules and regulations for building an ADU.

ADU info for

San Francisco

  • ADU allowed?
    YES
  • Number of ADUs allowed?
    1 ADU and 1 JADU
  • Max ADU Size
    1,200 SQFT
  • Eligibility
    most single-family and multi-family zoned properties
  • Setbacks
    minimum 4-foot setback from the side and rear property lines
  • Parking Requirements
    limited requirements, especially if the property is near public transit
  • ADU allowed?
    YES
  • Number of ADUs allowed?
    1 ADU
  • Max ADU Size
    750 SQFT
  • Eligibility
    R-5, R-4, and R-4A-zoned lots
  • Setbacks
    minimum 7-foot setback from the side and 15-foot rear property lines
  • Parking Requirements
    limited requirements, especially if the property is near public transit
  • ADU allowed?
    YES
  • Number of ADUs allowed?
    2 ADU
  • Max ADU Size
    1,000 SQFT (typically)
  • Eligibility
    Most residential zones
  • Owner Occupancy
    not required*
  • ADU allowed?
    YES
  • Number of ADUs allowed?
    1 ADU
  • Max ADU Size
    800-900 SQFT (typically)
  • Eligibility
    Varies but typically cities with population over 2,500; Counties over 15,000
  • Owner Occupancy
    Not required for most cases
  • Key Note
    Urban Growth Boundaries (UGBs) affect development location
  • ADU allowed?
    YES
  • Number of ADUs allowed?
    1 ADU
  • Max ADU Size
    Read details below.
  • Eligibility
    Read details below.
  • Setbacks
    Read details below.
  • Parking Requirements
    limited requirements, especially if the property is near public transit

Understand ADU zoning rules for

San Francisco

With Gather, designing your ideal ADU is a breeze. We manage all the planning and permitting paperwork, ensuring you enjoy a seamless experience and complete peace of mind.

Talk to a zoning expert
Schedule a free 30-minute call or call us now (323) 591-3717

Different types of ADUs allowed in

San Francisco

Though backyard homes are typically the most familiar, ADU structures come in various types. The illustration below shows the four primary types of ADU structures.

ADUs can be built using a variety of construction methods, including pre-fabricated, modular, shed, container, panelized (in pieces), and stick-built. Each construction method has its own advantages and disadvantages in terms of cost, time, and customization.

detached adu
Detached ADU
garage conversion adu
Garage Conversion ADU
addition / attached adu
Addition / Attached ADU
detached adu
Detached ADU
garage conversion adu
Garage Conversion ADU
addition / attached adu
Addition / Attached ADU
detached adu
Detached ADU
garage conversion adu
Garage Conversion ADU
addition / attached adu
Addition / Attached ADU
detached adu
Detached ADU
garage conversion adu
Garage Conversion ADU
addition / attached adu
Addition / Attached ADU

ADU regulations for

San Francisco

In a proactive effort to combat the ongoing housing crisis, the State of California has adopted specific regulations to promote the construction and utilization of Accessory Dwelling Units (ADUs). Here's an expanded and comprehensive breakdown of the key points:

1. Purpose and Prominence: California recognizes the potential of ADUs in providing affordable housing options. Given the state's dense urban centers and escalating property prices, ADUs present a viable solution to address the growing demand for residential spaces.

2. Eligibility for Establishment: Both single-family homes and multifamily properties can host an ADU.

3. Size Considerations: For detached ADUs, the maximum allowable size is up to 1,200 square feet.
The actual size of an ADU might vary depending on specific factors such as the total lot area and the size of the primary dwelling on the property.

4. Parking Norms: The state mandates limited parking requirements for ADUs.
If an ADU is situated near public transit, these parking stipulations may be even less stringent, facilitating easy construction and usage.

5. Owner-Occupancy: Historically, some jurisdictions required the property owner to live in either the primary home or the ADU. However, for ADUs permitted between 2020 and 2025, the state does not enforce such owner-occupancy requirements, allowing for greater flexibility in usage.

6. Setback Rules: For detached ADUs, there's a minimum setback requirement of 4 feet from both the rear and side yard boundaries.

7. Approval Process: Cities across the state are obligated to approve compliant ADU applications within a span of 60 days. This streamlined process ensures quick turnarounds and encourages homeowners to consider ADU development.

8. Fee Structure: To further incentivize ADU establishment, the state has reduced or completely waived fees for ADUs that are less than 750 square feet. This can translate to significant savings for property owners.

9. Rental Conditions: If an ADU meets the stipulated requirements laid out by the city, it must be available for rental. This regulation ensures that ADUs actively contribute to alleviating housing shortages.

10. Local Jurisdictional Variances: While the above guidelines provide a general framework, it's crucial to note that local jurisdictions might have their unique sets of regulations and requirements. Property owners should consult their respective city or county planning departments to get precise and localized information.

In conclusion, as California grapples with housing challenges, ADUs offer a promising avenue to augment living spaces without the need for expansive new developments. These guidelines, though comprehensive, serve as a starting point, and it's always recommended to liaise with local experts for tailored advice.

State laws (RCW 36.70A.680 and 36.70A.681) mandate that all local governments under the Growth Management Act (GMA), irrespective of size and including both cities and counties within unincorporated urban growth areas, update their regulations to align with specific criteria within six months following their scheduled update. The key directives include:

  1. ADUs per Lot: Urban areas within the GMA must allow at least two ADUs on any lot that qualifies by size, in addition to the main residence. These ADUs can be attached, detached, or a mix, and converting structures like garages into ADUs must be permitted.
  2. Size Requirements: ADUs cannot be restricted to under 1,000 square feet.
  3. Design and Location Standards: Restrictions on setbacks, lot coverage, tree preservation, or entrance placements cannot be stricter than those for the main home.
  4. Street Upgrades: ADUs cannot be subjected to demands for street improvements as a permit condition.
  5. Owner Occupancy: Requirements for the homeowner to live on-site are prohibited for both the main and accessory units.
  6. Condominium Sales: It’s not allowed to block the sale of a condominium developed as an ADU on the basis that it’s an ADU.
  7. Design Review: ADUs cannot face stricter aesthetic or design criteria than the primary residence.
  8. Parking: Parking requirements are limited, with specific conditions for smaller lots and exemptions for ADUs near major transit hubs.
  9. Impact Fees: Charges for ADUs are capped at 50% of those for the main house.
  10. Common Interest Communities: New developments with homeowners associations are barred from implementing rules against ADU construction. However, existing regulations can remain.

These regulations aim to encourage the development of ADUs, offering more housing options within urban growth areas.

Since July 1, 2018, most Oregon cities and counties allow homeowners to build Accessory Dwelling Units (ADUs) on residential properties. However, local rules on ADU size, placement, and design must be followed. Each area has its own rules for:

  1. How big the ADU can be;
  2. Where it can be located; and
  3. If it needs to look like the main house.

Local governments also have different processes for giving permits and may charge fees for building an ADU. These fees, including impact fees or system development charges, can vary a lot. Some places might not charge these fees at all, while others could charge $15,000 or more for each ADU.

In Oregon, the rules for creating Accessory Dwelling Units (ADUs) set standards to boost housing while keeping communities looking good. Understanding Oregon's ADU laws is crucial for compliance and making the most of ADU benefits. Cities must have over 2,500 people, and counties over 15,000, to fall under the ADU mandate. This supports urban housing needs. Urban Growth Boundaries (UGBs) define where ADUs can be built, promoting smart growth and land use without harming Oregon's landscapes.

Oregon's ADU laws aim to increase affordable housing. They require local governments to process ADU applications efficiently, especially in urban areas. State laws stop local rules from demanding owners live in ADUs or provide extra parking, except for vacation rentals. Setback requirements ensure ADUs are well-placed, respecting privacy and the environment. Oregon encourages updating local ADU rules to match state standards, making it easier to build ADUs and help with housing shortages.

Design and siting rules for Oregon ADUs ensure they fit well with urban settings and offer design flexibility. Oregon prefers less restrictive rules for ADUs compared to other buildings, aiming to increase housing options responsibly. The state simplifies ADU regulations, replacing complex zoning laws with clearer, state-wide standards. This helps reduce red tape and encourage ADU construction.

Oregon's approach to ADUs, including size restrictions and utility connection guidelines, is designed to integrate ADUs smoothly into neighborhoods, addressing housing needs. ADUs can't be too large compared to the main house, and shared utility connections are encouraged to keep costs down. This effort shows Oregon's commitment to innovative, affordable housing solutions.

  • Oregon ADU laws establish criteria to support housing while maintaining community aesthetics.
  • Cities over 2,500 people, and counties over 15,000, need to allow ADU construction per state mandates.
  • Urban Growth Boundaries (UGBs) are key to ADU development, limiting expansion within set geographic areas.
  • The state prohibits local ordinances from requiring owner occupancy or off-street parking for ADUs, except for vacation rentals.
  • Oregon mandates setback requirements for ADUs to ensure privacy and environmental standards.
  • Local governments in Oregon must update regulations to align with state ADU codes, promoting consistent and simplified ADU development.
  • Oregon ADU laws facilitate affordable housing by removing barriers to ADU construction and simplifying the application process.
  • Design standards for ADUs in Oregon are clear and objective, not requiring ADUs to mimic the primary residence's architecture.
  • Oregon's policies allow ADUs more flexibility in development compared to other accessory structures, avoiding strict lot size or coverage constraints.
  • ADUs in Oregon are subject to size limitations, generally not exceeding 75-85% of the primary dwelling's floor area, with specific square footage caps.
  • The state encourages the use of shared utility connections for ADUs to lower construction and development costs.
  • Oregon's comprehensive ADU regulations aim to expand housing options, reduce bureaucracy, and accommodate the state's diverse housing needs.
  • Why Homeowners Choose Gather

    Your one-stop ADU platform

    With Gather, you're not just building an ADU — you're cultivating peace of mind. Our end-to-end guidance and ongoing support mean every decision is informed, every step is intentional, and every outcome exceeds expectations. With us, your dream ADU is within reach. Here is what we do:

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    Design your perfect ADU

    With Gather, designing your ideal ADU is a breeze. We manage all the planning and permitting paperwork, ensuring you enjoy a seamless experience and complete peace of mind.

    Schedule a free ADU consultation
    Malibu
    Malibu
    1,000 SQFT
    3 Bed / 2 Bath
    Monterey
    Monterey
    750 SQFT
    2 Bed / 1 Bath
    Topanga
    Topanga
    600 SQFT
    1 Bed / 1 Bath
    Carmel
    Carmel
    500 SQFT
    1 Bed / 1 Bath
    Sonoma
    Sonoma
    400 SQFT
    1 Bed / 1 Bath
    Marina
    Marina
    300 SQFT
    Studio / 1 bath
    City Snapshot

    San Francisco

    883305
    Population
    309157
    Median Household Income

    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, 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:

    1. North Beach: Known as Little Italy, famous for its Italian heritage and beatnik history.
    2. The Mission: A vibrant, multicultural area known for its Latino roots and hipster vibe.
    3. Haight-Ashbury: The epicenter of 1960s counterculture, now a bohemian shopping district.
    4. Nob Hill: An affluent neighborhood known for its luxury hotels and stunning city views.
    5. SoMa (South of Market): A former industrial area now home to many of the city's museums and tech startups.
    6. 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:

    1. Golden Gate Bridge: The city's most famous landmark, an engineering marvel and icon of American design.
    2. Alcatraz Island: Former high-security prison turned national park and popular tourist destination.
    3. Fisherman's Wharf: Waterfront neighborhood known for seafood restaurants and sea lion sightings.
    4. Chinatown: The largest Chinatown outside of Asia and the oldest in North America.
    5. Cable Cars: The world's last manually operated cable car system, now primarily a tourist attraction.
    6. 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:

    1. Zoning: ADUs are permitted citywide in areas zoned for residential use.
    2. 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.
    3. Parking: No parking is required for ADUs. In fact, the ADU program allows for the removal of required parking to add an ADU.
    4. Owner Occupancy: As of 2020, there's no owner-occupancy requirement for either the primary residence or the ADU.
    5. 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.
    6. Rent Control: ADUs in buildings constructed before June 13, 1979, are subject to the city's rent control ordinance.
    7. 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.

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    Frequently Asked Questions

    What is an ADU and how can you help me build one?

    An ADU, or Accessory Dwelling Unit, is also known as a tiny home, granny flat, in-law unit, or garage apartment. We help homeowners by providing expert guidance and tools to navigate the process of building an ADU, from zoning and permitting, to design and size considerations, to cost estimation, and through the construction process itself.

    How can I determine if my local area allows for ADU construction?

    Our services include assistance with zoning and permitting. We help you identify your property's specific zoning requirements and the necessary permits for ADU construction, ensuring your project stays compliant with local regulations.

    What does the construction process for building an ADU look like?

    We offer information and resources on the construction process, timelines, and best practices for building an ADU. Additionally, we have a network of trusted builders you can partner with to ensure a seamless, efficient, and high-quality build for your ADU.

    What is included in your feasibility report for building an ADU?

    With the Gather Feasibility Report, you can confidently embark on your ADU journey, knowing you've got a solid foundation and a clear roadmap to success. Let us help you transform your space into a functional, comfortable, and profitable asset today.

    We
       
    1) Thoroughly analyze your property records for a tailored assessment,        
    2) Work with city and county authorities on your behalf for a hassle-free experience,        
    3) Secure a preliminary "pre-approval" from city/county for your peace of mind,        
    4) Deliver a comprehensive report document detailing your property's ADU possibilities.            

    Embark on your ADU adventure with Gather ADU, and make the most of your property's potential without the stress or hassle.

    Do I have to commit to the entire ADU construction project right away?

    No, it isn't required. GatherADU offers support at every step of the ADU process, allowing you to proceed without making an immediate full commitment. You have the flexibility to progress at your own pace and opt for pay-as-you-go.

    Where does GatherADU operate?

    GatherADU provides ADU design and planning services nationwide with focus on California, Washington, Oregon, and Georgia.