California ADU Planning Resources

Planning an accessory dwelling unit involves both the proposed home and its relationship to the existing property. Begin with current state guidance, then confirm the application requirements for the project address.

We prepare the site-plan component within an agreed drafting scope. Architectural design, structural calculations, surveys and other licensed work may also be required.

Start With Official State Guidance

The California Department of Housing and Community Development maintains official ADU resources and its ADU Handbook. Check the current version when evaluating your project; do not rely on an old summary of state law.

Identify the Project Type

State whether you are considering a detached ADU, an attached addition, an existing-space conversion, a garage conversion or a JADU. The site drawing and the rest of the permit package must describe the same project.

Confirm the Local Submission Path

Use the property address to confirm the reviewing city or county. Obtain the applicable ADU checklist, drawing requirements and application instructions. Our location guides provide links to public permit resources for published cities.

Plan the Property-Level Drawing

Gather information about the main residence, proposed unit, existing garage, access, driveways, other structures and relevant utility information. Show existing and proposed work distinctly. Setbacks, easements and other controlling conditions need reliable source information.

Coordinate With the Other Drawings

The site-plan footprint and labels should match the architectural drawings. If engineers or other specialists are involved, clarify which team member supplies each item. A drafting estimate should not imply that all professional disciplines or permit fees are included.

Prepare the Documents

Collect prior plans, available surveys, property photographs, the project sketch and any written agency comments. Use our preparation checklist to organize the brief.

Use Feasibility Tools Carefully

Online tools can help organize questions, but a result is not a permit decision or verified property determination. Current official requirements and a review of the actual site remain necessary before proceeding.

Request ADU Site-Plan Support

Review our ADU and JADU drafting service and send the project details for a scope review.