Building an ADU in San Francisco
Short answer: San Francisco allows ADUs in every zoning district that permits housing, through two paths: the State ADU program, which is ministerial and more flexible on Planning Code rules, and the Local program, which requires in-house Planning review. Type Five, a Berkeley design-build firm, designs your ADU, handles San Francisco permitting, and builds it on site.
San Francisco ADU rules to know
- Two programs: the State program is ministerial and does not require compliance with Planning Code items like rear yard and exposure; the Local program allows ADUs added to existing or proposed buildings but needs in-house Planning review and a Planning Approval Letter before you apply to the Department of Building Inspection (DBI).
- Eviction history: under the Local program, ADUs cannot be added to buildings with an owner move-in eviction in the last 5 years or a no-fault eviction in the last 10 years.
- Use: ADUs cannot be used as short-term rentals, in most cases cannot be sold separately, and may be subject to the city's rent ordinance (Administrative Code Section 37.2).
- Applying: permits are submitted through the PermitSF portal, Online Contractor Permits, Over-the-Counter, or In-House Review depending on scope. DBI also runs a pre-approved detached ADU design program.
- State law still applies: the city must approve or deny a complete ADU application within 60 days when there is an existing home on the lot (Gov. Code 66317).
Sources: SF Planning, Accessory Dwelling Units (https://sfplanning.org/accessory-dwelling-units); SF.gov, Get a building permit for an ADU (https://www.sf.gov/get-a-building-permit-for-an-accessory-dwelling-unit-adu); SF.gov, Check if you can add new ADUs (https://www.sf.gov/see-if-you-can-add-new-units-your-residential-property).
How we work in San Francisco
We start with a site review to decide which program fits: the State path is often simpler for a detached backyard unit, while the Local path can allow designs the State program does not. From there we design the home, prepare the plan set, take it through Planning and DBI, and build it on site with wood framing.
Our completed backyard homes are in the East Bay and Marin; the projects below show the design approach and finish quality you can expect.
Planning an ADU in San Francisco?
Tell us about your property and we'll help you choose the right program and plan your project.
How our process works
Design, permitting, and construction under one roof.
San Francisco ADU FAQs
What San Francisco homeowners ask us.
Should I use the State or Local ADU program?
It depends on your lot and design. The State program is ministerial and skips several Planning Code requirements; the Local program can allow other configurations but adds Planning review. We assess both during the site review.
Can I rent out my San Francisco ADU?
Yes, for longer-term tenancies. Short-term rentals are not allowed, and the unit may be covered by the city's rent ordinance, so review Administrative Code Section 37.2 before you set rents.
How long does an ADU take with Type Five?
Most projects take about 10 to 12 months from first design meeting to move-in: roughly one month of design, two to four months of permitting once we submit, and about six months of construction. Planning review under the Local program can add time.
Who handles permits?
We do: Planning approval, the DBI building permit, fire-department sign-off, and utility coordination. You sign an authorization form and we handle the rest.
Are you a prefab company?
No. Every Type Five ADU is built on site, which helps on San Francisco's narrow lots where cranes and oversized trucks are impractical.