ADUs
An accessory dwelling unit on a coastal San Diego lot is not a simple construction problem. It is a zoning problem, a permitting problem, a design problem, and a construction problem — in that order. The contractors who treat it as only the last one produce units that take twice as long and cost significantly more than the estimate. We approach ADU work the same way we approach the primary home: resolve the hard questions before breaking ground.
Why the coast is different
State ADU law has liberalized substantially since 2020, but it layers on top of local municipal codes, HOA restrictions, Coastal Commission jurisdiction, and lot-specific constraints that vary block by block in neighborhoods like Point Loma and Coronado. A lot with a 40-foot height limit, a view preservation overlay, and an HOA design review board presents a different problem than one without any of those layers — even when both are technically eligible for an ADU under state law.
We work with architects and permit expediters who specialize in this jurisdiction. The pre-construction phase on an ADU — site analysis, zoning research, design development, permit submittal — typically runs 3 to 6 months before a shovel is in the ground. The build itself, once permitted, runs 4 to 8 months depending on scope. Timelines communicated before that pre-construction work is complete are guesses.
Types of ADUs we build
Detached ADU
A fully independent structure on the same lot — the highest-value option in most markets. Requires the most permitting legwork and the most site coordination, but delivers a genuinely separate residence.
Attached ADU
An addition that shares a wall with the primary home. Common where lot coverage limits rule out detached. Requires careful attention to sound, fire separation, and access.
Garage conversion
Coastal lots often have garages that are underused or detached already. Converting one can be the most cost-efficient path to a permitted unit — if the existing structure's envelope, electrical, and mechanical can support it.
Junior ADU (JADU)
A unit carved from existing interior space — typically a large bedroom or a portion of the home. Limited by state law to 500 sq ft and must share a wall with the primary residence. The permitting path is significantly lighter.
What this scope includes
ADU construction scope covers site work and foundation, framing, roofing, exterior envelope, windows and doors, all MEP rough-in and trim-out (plumbing, electrical, HVAC), insulation, drywall, flooring, cabinetry, countertops, tile, fixtures, and hardware. For detached units, this includes a dedicated utility connection and a separate address through the city. Landscaping, hardscape, and fencing affected by construction are coordinated — if our crew disturbs it, we restore it.
Permit coordination and inspections are part of how we work, not a separate line item. A permitted, inspected ADU is an asset; an unpermitted one is a liability the next buyer will discount.
Investment
Detached ADUs in coastal San Diego typically run $350K–$650K depending on size, finish level, and site conditions. Garage conversions and JADUs can fall meaningfully below that range; two-story detached units on constrained lots can exceed it.
The investment range is wide because the variables are wide. What changes the number most: whether the existing utilities can support a new unit without a panel upgrade or a new sewer lateral, whether the site requires significant grading, and the finish level relative to the primary home. We can usually bracket the range after a site visit and a review of the lot data — before an architect is engaged.
Start with the site, not the design.
Before an ADU conversation goes anywhere useful, we need to understand what the lot will allow. Bring us the address and we can usually tell you in one meeting what is realistic, what the permitting path looks like, and what the range of investment is before you spend anything on architecture.