Accessory Dwelling Units in the San Francisco Bay Area
Clever Design & Remodeling offers accessory dwelling unit (ADU) construction services throughout the San Francisco Bay Area. For property owners looking to add living space, generate supplemental rental income, or increase home value, an ADU can be a practical solution. The company is licensed, bonded, and insured, and brings project management experience to each build.
San Francisco's ADU program was initially authorized in 2016 and is now available citywide for both single-family homes and multi-family residential buildings. Accessory dwelling units are sometimes referred to as in-law units, casitas, granny flats, or secondary units. All new units must comply with current building codes, and local ADU legislation governs how community development proceeds.
Types of ADUs Clever Design & Remodeling Builds
There are four main types of accessory dwelling units commonly built in San Francisco. Clever Design & Remodeling has experience working across all four categories:
- Conversion ADU: An existing space within the primary structure — such as a garage or sunroom — is converted into a dwelling unit. A garage conversion can be a cost-effective alternative to new construction, though it still requires planning code compliance and a building permit application.
- Attached ADU: An additional unit connected directly to the primary residence, complete with its own sleeping area, kitchen, living space, and bathroom. California building code requires each bedroom to have a rescue opening. Attached ADUs are generally less expensive than detached units, though total square footage is subject to state and local limits.
- Detached ADU: A fully independent structure separate from the primary home. A detached ADU builder must ensure the unit is structurally independent. Detached units can offer greater rental income potential due to the privacy they provide tenants. Note that off-street parking requirements typically apply to detached ADUs in San Francisco.
- Junior ADU (JADU): A unit built within an existing single-family home, not exceeding 500 square feet. JADUs are permitted in any zoning district that allows single-family dwellings. They are limited to long-term rentals only. A JADU can be created by adding a kitchen and an exterior-facing door, and may include a private or shared bathroom.
Each type of ADU comes with its own set of regulations, costs, and considerations. The average cost of an ADU for single and multi-family properties is approximately $145,000, though this varies significantly by type. Junior ADUs tend to be considerably less expensive, while detached units for multi-family properties sit at the higher end of the cost range. Garage conversions typically range between $25,000 and $100,000.
Planning, Permits, and Construction
Building an ADU in San Francisco involves navigating a range of regulations, including zoning district rules, state law, the state ADU mandate, rent control provisions, historic resource considerations, and street tree requirements. Clever Design & Remodeling works with property owners through the planning and permitting process, including pre-application meetings and applications for any necessary waivers with the zoning administrator.
The company's planning department reviews the existing space and any current units on the property, then helps determine which ADU type best fits the homeowner's goals and budget. Owner occupancy requirements do not apply to new ADUs in San Francisco through 2025.
Once permits are secured, the construction team handles the full build — from construction drawings and architecture to interior finishes, cabinetry, flooring, and the installation of required safety features such as smoke alarms and detectors. Clever Design & Remodeling also offers interior design services and customizes each build to the client's preferences.
Beyond the structure itself, the company provides landscape design services to complete the exterior of the property. This includes water fixtures, exterior lighting, front door and window detailing, garden construction, and irrigation installation.
For property owners in the San Francisco Bay Area considering a backyard cottage, in-law suite, casita, or any other form of accessory dwelling unit, Clever Design & Remodeling offers end-to-end services from initial consultation through final inspection.
