Pre Approved ADU Plan Directory

The California Pre-Approved ADU Plan Directory is a statewide online collection of ready-to-use accessory dwelling unit (ADU) building plans that have already been reviewed and accepted for compliance with key state building, safety, and zoning standards. In accordance with Assembly Bill 1332 (effective January 1 2025), each jurisdiction in California is required to offer a program for plan pre-approval and maintain an online list of those plans.

Key features:

• The directory enables property owners, developers, architects, and designers to browse a curated set of ADU plan-sets that have been pre-reviewed for site-agnostic portions of compliance (structural, plumbing, electrical, etc.).

• Once a pre-approved plan is selected, the property owner works with the plan-owner/designer to adapt the site-agnostic plan to their specific lot and submit the site-specific application for permit. This two-step process (pre-approval then site-specific) is mandated by AB 1332.

• The directory typically includes: floor plans, elevations, structural details, building code compliance info, and designer contact information. It may also include site-plan templates, foundation information and other supporting documents.

• For homeowners and developers, using a pre-approved plan can reduce design cost, shorten permitting time, and streamline the build process. Several municipalities report dramatically faster turnaround when a plan is used “as is.”

• For local governments, the directory helps satisfy the statutory requirement for plan-pre-approval and listing, while also helping to ramp up ADU production in a housing-constrained state.