Del Mar ADU rules and permits
Del Mar's ADU rules are in Chapter 30.91, certified by the Coastal Commission and effective June 12, 2025 (City of Del Mar ADU page; Del Mar Municipal Code Chapter 30.91 (June 2025)).
At a glance
| Topic | Rule |
|---|---|
| Zones | Any residential or mixed-use lot with a home, including CVPP residential lots 3-9, 11-17, 20-29 |
| Per lot | One ADU and one JrADU (JrADU only with a detached ADU) |
| Detached size | 850 sq ft; 1,000 with more than one bedroom; 800 universal |
| Attached size | 50% of house; 800 if house under 1,600 sq ft |
| Height | 16 ft detached (18 near major transit; 14 in Bluff, Slope and Canyon Overlay) |
| Setbacks | 4 ft side/rear; zone street setbacks; coastal setbacks |
| Parking | None near major transit; one space in some shoreline/wildfire and narrow-street cases |
| Rentals | Longer than 30 days; no separate sale |
| Permits | Building permit plus Administrative CDP unless exempt |
| Design | Objective standards; exempt from Design Review |
| Tiny homes | Processed as ADUs |
Exempt from discretionary permits
- Design Review Permit
- Land Conservation Permit for grading within the ADU footprint (grading permit still needed)
- Floodplain Development Permit if within existing habitable space or properly elevated
- Conditional Use Permit in the Bluff, Slope and Canyon or Coastal Bluff overlays with required setbacks
Contact
City Hall: 858-755-9313. The city encourages applicants to contact Planning first.
Permit map
| Permit | When |
|---|---|
| ADU permit (ministerial) | Every ADU and JrADU |
| Administrative CDP | Most new ADUs, unless exempt |
| Encroachment permit | Any right-of-way work |
| Tree permit | Protected tree impacts |
| Building permits | After ADU approval |
Engineering
| Project | Engineering review? |
|---|---|
| New attached ADU | Yes |
| New detached ADU | Yes |
| ADU inside the house or an existing accessory structure | No |
| Garage converted to an ADU | No |
Source: Del Mar ADU Application Packet, Engineering ADU Plan Requirements.
Also checked Oct 14, 2026: Del Mar ADU Application Packet (Rev. 2024) · HCD ADU Handbook (March 2026).
Sources, checked Oct 14, 2026: City of Del Mar ADU page · Del Mar Municipal Code Chapter 30.91 (June 2025).
Questions
When did Del Mar's current ADU rules take effect?
June 12, 2025, on Coastal Commission certification of Chapter 30.91.
How many ADUs can a Del Mar single-family lot have?
One ADU plus one JrADU, and the JrADU only if the ADU is detached.