Coastal letter first

Most cities start ADU review at their own counter. Solana Beach's handout puts the Coastal Commission letter in the first email you send (Solana Beach ADU Submittal Process and Basic Plan Requirements (June 2025)). That changes the order of work.

What to do in parallel

• Topographic survey and grading quantities (the 50 cubic yard cap)
• FAR worksheet
• Sewer lateral location
• Landscape area check (500 sq ft trigger)

Why it helps

A design that already meets the city checklist means the coastal set and the city set match, and nothing has to be redrawn twice. See coastal approval.

The full first-submittal list

1. Get the Coastal Commission approval letter; the city asks for it with the application.
2. Email the building permit application, a PDF plan set and the coastal letter to counter@cosb.org.
3. The Building Permit Technician invoices plan check and address assignment fees, based on scope, size and valuation.
4. After payment, plans route electronically to Planning, Building, Engineering and Fire, plus the third-party landscape reviewer if a landscape package is required.
5. Planning assigns the ADU's new address during first review; it then goes on the plans.

Other early checks

• Fire sprinklers in the house?
• Fire access within 150 ft
• Solar for new detached
• Separate address

The 60-day rule

Per HCD, the Coastal Commission has 60 days from a complete application where the city has no certified LCP, and must act concurrently with the ADU review.

Also checked Oct 14, 2026: HCD ADU Handbook (March 2026).

Sources, checked Oct 14, 2026: Solana Beach ADU Submittal Process and Basic Plan Requirements (June 2025).