What Documents Are Required for an ADU Permit?

Applying for an Accessory Dwelling Unit (ADU) permit involves more than just filling out a form. A very important early question is: What documents must be prepared to get an ADU permit approved smoothly?

Submitting a complete, organized set of documents — including a detailed ADU blue print and a permit ready ADU plan — makes a major difference in approval speed.

Core Documents for an ADU Permit Application

1. Site Plan

Shows the full property layout, including:

• Property lines and setbacks

• Location of the primary home and the proposed ADU

• Driveways, walkways, and parking spaces

A precise site plan helps cities verify zoning compliance for your ADU permit.

2. Floor Plan

Includes:

• Room layouts with dimensions

• Window and door placements

• Kitchen and bathroom arrangements

A clean, professional ADU blue print ensures clarity for plan reviewers.

3. Building Elevations

Illustrates:

• Exterior views from all sides

• Building heights

• Roof pitches and materials

Using a preapproved ADU plan often speeds up review since elevations are already approved.

4. Structural Details

Shows:

• Foundation design

• Wall and roof framing

• Structural connections and seismic reinforcements

Critical for city engineers to verify safety compliance.

5. Title 24 Energy Compliance Report

California requires all ADUs to meet energy efficiency standards:

• Insulation

• Windows

• HVAC systems

This Title 24 documentation must match the submitted permit ready ADU plans.

6. Plumbing, Electrical, and Mechanical Plans

Includes:

• Water and sewer line layouts

• Electrical panel upgrades, circuits, and outlets

• Heating, cooling, and ventilation systems

Good PME plans make city inspections faster and smoother.

7. Owner Declarations and Affidavits

Some cities require:

• Owner-occupancy affidavits (for JADUs)

• Historic property declarations

• Utility connection agreements

Preparing these forms early prevents delays during permit intake.

Optional but Helpful Documents

• Soil reports (if major grading is involved)

• Tree protection plans (for lots with protected trees)

• HOA approvals (if located in private communities)

Real-World Example

A homeowner in Santa Rosa submitted a complete package — including a site plan, detailed ADU blue print, and Title 24 reports aligned with a preapproved ADU plan.Their ADU permit was approved in just five weeks, with no correction cycles required.

Common Mistakes to Avoid

• Forgetting Title 24 energy reports

• Submitting incomplete site plans

• Omitting required owner declarations

• Using unclear or non-code-compliant ADU blue prints

Final Thoughts

Submitting a complete, professional ADU permit package dramatically increases the chances of fast approval and a smoother construction process. At ADUnest, we specialize in preparing clear ADU blueprints, assembling full document sets, offering preapproved ADU plans, and delivering permit ready ADU plans designed to move through city approvals efficiently.If you have questions about document preparation for your ADU project, feel free to leave a comment below — the ADUnest team will help guide you through it every step of the way!