ADU builders and rules in Del Mar

Del Mar ADU rules

Del Mar's ADU rules are in Municipal Code Chapter 30.91. The city adopted the current version as Ordinance No. 1002 on December 18, 2023, but because it also amends the Local Coastal Program, it couldn't take effect until the Coastal Commission certified it. According to the city's ADU page, the Commission conditionally certified it on March 13, 2025, the City Council accepted the required changes on May 19, 2025, and the rules took effect June 12, 2025. The city posts the full June 2025 text of Chapter 30.91; the table below summarizes it.

Lots with an existing duplex can add up to two ADUs, and buildings with three or more units can convert unused space into ADUs for up to 25% of the units, plus two detached ADUs, under the same city guidance.

Del Mar's design standards

Del Mar applies a long list of objective design standards to new ADUs, unless they would make an 800 sq ft ADU impossible. Under Section 30.91.040:

• Rooftop decks are prohibited, including on a second-story ADU.
• Glass walls visible from neighboring homes are prohibited, and windows must be staggered from the neighbor's or use obscured glass, clerestories or higher sills.
• An ADU attached to the house or within 20 feet of it must match the house's style, roof pitch, materials and colors.
• Wall and roof planes need a projection or recess of at least one foot for every 20 feet.
• Exterior lights must be shielded, 2700 Kelvin or warmer, and Dark Sky certified; outdoor speakers and TVs are banned.
• No building inside the dripline of a protected Torrey pine or Monterey cypress, and grading is capped at 200 cubic yards.

The city adopted these partly because, as the ordinance's findings put it, residents testified that ADUs were being built as home offices, recreation rooms and ways to gain ocean views rather than as housing. Plan your ADU as a real dwelling with a full kitchen and bathroom. The state rules behind all this are in California ADU laws; see also our junior ADU guide and two-story ADU guide.

We couldn't find a state housing department (HCD) review letter on Del Mar's ADU ordinance.

Coastal permits for every Del Mar ADU

Del Mar is located entirely within the coastal zone, so ADU projects must meet the Coastal Act and the city's Local Coastal Program. Under the current code, an ADU needs an Administrative Coastal Development Permit unless it is one of two exceptions: a conversion of existing, legally built living space inside the house that doesn't remove or replace major structural parts like the roof, exterior walls or foundation, or an attached ADU that already qualifies as exempt under the Coastal Commission's regulations.

That is stricter than Del Mar's old rules. The Coastal Commission's staff report notes that the city's 2018 provisions exempted most ADUs outside the Commission's appeal area from coastal permits; the Commission narrowed that exemption as a condition of certifying the 2023 ordinance.

The administrative coastal permit adds steps, but no public hearing:

• City staff give you a notice card to post at the site, and your plans are available for public review at City Hall.
• After approval, the city mails notice to owners within 300 feet and occupants within 100 feet, and to the Coastal Commission.
• If your lot is in the Coastal Commission's appeal area, the approval can be appealed to the Commission within 10 working days.

The code also keeps coastal setbacks in force. A new ADU must respect the coastal bluff setback, the Beach Preservation Initiative setback in the Beach Overlay Zone, steep-slope and wetland buffers, and, where needed to protect public views to the ocean, the zone's full side and rear setbacks. ADUs are not allowed on a beach, in a wetland or habitat area, or in a designated highly scenic area. If adding an ADU leads to redevelopment of a house that doesn't meet bluff, view or habitat setbacks, the city requires you to correct those nonconforming conditions.

Del Mar ADU parking near the beach

Most California cities can't require parking for an ADU near transit. Del Mar can in two situations, to protect public beach parking and emergency access. Under Section 30.91.040(P):

• Coastal appeal area. On lots inside the Coastal Commission's appeal jurisdiction, a new ADU needs one off-street space (covered or uncovered). Exceptions include ADUs inside the existing house or an existing accessory building, historic properties, and lots within one block of a car-share spot. The general half-mile-from-transit exemption doesn't apply there, but ADUs within a half mile of a major transit stop need no parking anywhere in the city.
• Narrow streets. If your lot is reached by a street 20 feet wide or less, the ADU needs one off-street space, which can be tandem or in a driveway or setback.

If you convert or demolish a garage, the city requires replacement parking only if losing it would significantly affect public access to the shoreline. The application asks whether your lot is between the ocean and the first public road, so check that early. For garage projects, see our garage conversion ADU guide.

Fire, flood and bluff zones in Del Mar

The state's 2025 fire hazard maps significantly expanded the parts of Del Mar designated High and Very High Fire Hazard Severity Zones, especially neighborhoods next to open space. The City Council adopted the maps on June 16, 2025. New construction in those zones must meet Chapter 7A of the California Building Code for wildfire-resistant construction. You can look up your parcel on the city's map viewer linked from that page.

On a lot that is wholly or partly in a Very High zone, Del Mar's ADU code requires you to show at least two emergency evacuation routes and prepare an evacuation map for the parcel, or prove an equivalent safety measure. ADUs in the FEMA flood zone must be elevated and floodproofed with sea level rise in mind, with height measured from the base flood elevation, and ADUs on coastal bluff lots need a geotechnical report. These requirements add design and consulting time, so build them into your budget and schedule.

Del Mar sample ADU floor plans

We found no Del Mar program of permit-ready, pre-approved ADU plans of the kind that state law encourages. What the city does offer, paid for with a state SB 2 planning grant, is three free sample floor plans by Stephen Dalton Architects, designed to meet state law and the city code and to be fully ADA accessible:

They are floor plans only, in PDF and CAD, so you still need full construction drawings, a site plan and the coastal permit. The 955 sq ft plan has two bedrooms, which fits under Del Mar's 1,000 sq ft limit for multi-bedroom ADUs. For other plan libraries in the region, see our pre-approved ADU plans guide.

Del Mar ADU fees

Engineering review is required for new attached and detached ADUs, but not for ADUs inside the house, inside an existing accessory structure, or in a converted garage, according to the city's ADU application packet. The fee schedule doesn't list an ADU building permit fee, so ask the Building Division for an estimate. Under state law, a city can't charge impact fees on an ADU under 750 sq ft, and above that the fee must be proportional to the main house.

San Dieguito Union High School District's fee page says it also collects school fees for the Del Mar Union and Solana Beach elementary districts, by appointment and by check only. For what an ADU costs to build, see what an ADU costs in San Diego or run the ADU cost calculator.

Del Mar ADU incentive and amnesty programs

Del Mar's housing plan sets a goal of 15 ADUs rented to low-income households by April 2029, according to the city. Two programs support it:

• ADU Incentive Program. If you agree to rent an ADU to a low-income household under a deed restriction (the city's incentive page says at least 30 years), Section 30.91.070 lets a single-family or duplex lot add a bonus junior ADU of up to 500 sq ft plus a 500 sq ft floor-area bonus. A contract with the city and an administrative coastal permit are required.
• ADU Amnesty Program. Owners with unpermitted ADUs that existed by April 15, 2021 could legalize them with a free initial inspection and five years to bring the unit up to code. City Council Policy 119 waives permit fees by 50% for moderate-income rentals and 100% for low-income rentals, and up to $500 of code enforcement fines for market-rate units. The city's incentive page says the program runs through December 4, 2025, and we couldn't confirm an extension; ask the planning department if it's still open.

If you're weighing rent against cost, see ADU rental income in San Diego.

Getting a Del Mar ADU permit

Applications go to the Department of Planning and Community Development at City Hall, 1050 Camino del Mar. The application packet lists phone 858-755-9313, email planning@delmar.ca.us, and counter hours of Monday and Wednesday, 1 to 5:30 p.m. You submit:

• The uniform development application and ADU verification form from the packet, with the city's fees.
• A plan set with dimensioned site plan, floor plan, elevations and cross sections, plus a stormwater checklist.
• For new attached or detached ADUs, an engineering submittal including a preliminary title report and a plumber's video certifying the existing sewer lateral.

Before the building permit is issued you must record a deed restriction with the County Recorder covering the ADU's sale, occupancy and rental limits, and the city requires a certification of height, setbacks and square footage before framing inspection. Once your application is complete, state law gives the city 60 days to approve or deny it, and the city's ADU page says compliant plans will be approved within that window. An ADU permit expires after two years if no certificate of occupancy has been issued.

Before you sign a contract, read how to hire an ADU contractor, check a contractor's license, and compare verified ADU builders in San Diego County.

Common questions