Pre-approved design plans for accessory dwelling units (ADUs) are now available to property owners living in unincorporated parts of Santa Barbara County.
The county has multiple sets of construction plans for ADUs available to download for free from its website.
Accessory dwelling units are small housing structures that can be attached to a single-family home, in a converted garage, or built on a property as a standalone unit.
The plans are standardized construction documents that are designed to match the county’s existing building code and the size and height allowed under the basic zoning standards.
The plans are pre-approved for property owners living in unincorporated parts of the county, but not for those living within the boundaries of incorporated cities. (Some cities, like Carpinteria, have already OK’d their own pre-approved plans for ADUs.)
In a June 2025 meeting with the Board of Supervisors, Planning and Development Director Lisa Plowman said providing pre-approved options for homeowners reduces red tape.
Homeowners can save up to $25,000 by using a pre-designed county plan instead of paying for their own new design, county staff said.
In a statement announcing that the pre-approved plans are now available, Plowman said ADUs are a “key part of our strategy to increase housing options for residents at all income levels.”
Pre-approved building plans are part of the county’s goal of building more housing throughout the region. The county is required by state law to plan for 15,000 more housing units by 2031.
The new ADU plans are available in different sizes and layouts. Homeowners can choose plans ranging from studio apartments to single and multiple-bedroom designs.
The designs include a 480-square-foot studio, a 672-square-foot one-bedroom, a 909-square-foot two-bedroom, and 768-square-foot two- and three-bedroom options.
Homeowners can also choose between traditional and modern designs, such as farmhouse, California ranch, and Mediterranean.
The county warned that plans may not be suitable for sites with steep slopes, unstable soils, flood hazards, or other conditions that may require special engineering or designs.
Properties in the Coastal Zone still require a Coastal Development Permit for any ADUs. The ADU must also follow all applicable zoning standards.
Applicants must also apply for all necessary county permits and submit plans for their specific site. County staff can answer questions about eligibility, lot feasibility, and the building permit process.
For more information, visit the County’s ADU website, contact the South Coast Permit Resource Center at 805-568-3030 or padbuild@countyofsb.org, or contact the North County Permit Resource Center at 805-934-6397 or ncbuild@countyofsb.org.
