Free 48-hour feasibility report
Find out what an ADU would earn on your San Diego lot.
Enter your address. In 48 hours you get a feasibility snapshot: what you can likely build, what it roughly costs, and what it rents for in your zip code. Free, no site visit required.
CSLB B #970145
Designed, permitted, built by one team
San Diego since 2004
How much does an ADU cost in San Diego in 2026?
As of 2026, most detached ADUs in San Diego cost between $180,000 and $350,000 to design, permit, and build, and rent for $1,900 to $3,200 per month depending on size and zip code. Where your lot lands inside that range depends on what you build — that is the question the feasibility report answers with your address, your zoning envelope, and rent comps for your zip.
Attached studio / 1BR
Typically the most affordable path
Built onto or converted from existing space. Shares walls and utilities with the main house, which keeps the build at the lower end of the 2026 range.
Detached 1BR
The most common San Diego build
A standalone backyard unit with its own entrance. Mid-range build cost, strong rental demand in nearly every zip code we serve.
Detached 2BR
The top of the range — and of the rent band
The largest standard ADU. Highest build cost of the three, and the configuration that commands the top of the $1,900–$3,200 monthly rent band.
Updated July 2026. Ranges reflect typical San Diego design, permitting, and construction costs; your report prices your specific lot. Exact per-plan figures are confirmed in your feasibility report, not estimated from averages.
What the report models
Three ways a San Diego lot turns into income.
Projection — modeled per lot
The backyard rental
A detached unit rented long-term. The report models your build range against real rent comps in your zip, so the payback math is your math, not a brochure's.
Projection — modeled per lot
The family setup
Parents, adult kids, or a caregiver close by, with a separate entrance and full kitchen. The report shows what fits your setbacks before anyone draws a floor plan.
Projection — modeled per lot
The resale play
A permitted, rent-ready ADU changes what your property is worth and who bids on it. The report frames the value case with your lot's actual buildable envelope.
Why the report beats a contractor visit.
Most ADU conversations start with a salesperson at your kitchen table. Ours starts with your lot's actual numbers.
No salesperson in your kitchen. The report arrives by email; the follow-up call is optional and yours to book.
Real rent comps for your zip code, not county-wide averages that flatter the pitch.
Know your lot's answer before you talk to anyone — zoning envelope, likely build type, cost range, rent range.
How it works.
Step 1
Enter your address
Plus your goal and timeline. Two minutes, no documents needed.
Step 2
We analyze the lot
Zoning envelope, setbacks, existing structures, and rent comps for your zip code.
Step 3
48-hour report
What you can likely build, what it roughly costs, what it rents for. Delivered Monday to Saturday.
Step 4
Optional 30-minute call
Walk the numbers with the team that would design, permit, and build it.
Planning a bigger project around the ADU? See whole-home renovations or get the full 2026 San Diego remodel cost guide. The classic service overview lives at ADUs & additions.
San Diego ADU questions, answered directly.
Do I need a permit to build an ADU in San Diego?+
Yes. Every ADU needs a building permit, and California law requires cities to review complete ADU applications ministerially — no public hearing — within 60 days. We handle the design, the permit package, and the build as one team, so the paperwork is our job, not yours.
What did California's ADU laws change?+
State law now requires ministerial (no-hearing) approval for ADUs that meet objective standards, removes owner-occupancy requirements for most ADUs, and allows an ADU plus a junior ADU on most single-family lots. SB 9 is separate — it covers lot splits and duplexes — but together they dramatically expanded what a San Diego lot can hold.
Can I build an ADU over my garage?+
Usually, yes. Garage conversions and above-garage ADUs are both recognized paths under California ADU law, and conversions of existing space are often the fastest to approve. Structural feasibility for a second story depends on the existing garage — that is exactly what the feasibility report checks first.
How long from permit to keys?+
Plan on roughly a year end to end for a detached ADU: design and permitting typically take a few months (the city must act on a complete application within 60 days), and construction typically runs 6 to 9 months depending on size and site. Your report includes a timeline estimate for your specific lot.
Can I finance an ADU?+
Yes. Most owners fund ADUs with home equity (HELOC or cash-out refinance), renovation loans, or construction financing; California has also periodically offered ADU grant programs. We are builders, not lenders, so we don't give financial advice — but the report gives you the cost number you need to have that conversation with your lender.
Does an ADU raise my property taxes?+
Only on the new construction. In California, adding an ADU triggers a supplemental assessment on the value the ADU adds — your existing home is not reassessed. Your county assessor sets the exact figure once the ADU is complete.
Your lot already has an answer. Get it in writing.
Reports delivered within 48 hours, Monday to Saturday. Free, and yours to keep whoever you build with.
Takes about two minutes