Garage Conversion
Garage Conversion ADUs in the Bay Area
Your garage is already a foundation, four walls, and a roof in the right place. We turn it into a $2,500+/month rental unit.
Most Bay Area garages store everything except cars. Converting that under-used 400 square feet into a legal rental unit is the highest-leverage construction project per dollar in California: the foundation, structure, and roof already exist, state law has stripped away parking-replacement requirements, and the rental market on the other side is Silicon Valley's.
A legal conversion is more than drywall and a Murphy bed: foundation moisture sealing, insulation to Title 24, a proper kitchen and bath, egress, and separate heating. We engineer all of it for permits that sail and a unit that rents at the top of its bracket.
What's included
Attached & Detached Garages
Both convert; detached garages make especially private rentals.
Full Legal Unit Build-Out
Kitchen, bath, laundry hookups, mini-split HVAC, and sound insulation from the main home.
Foundation & Moisture Engineering
Slab vapor sealing, sub-floor systems where needed, and drainage corrections — the steps amateurs skip.
Facade Transformation
Garage doors become glazed walls and entries; the result reads 'cottage,' not 'converted garage.'
No Replacement Parking
State law bars cities from requiring you to replace the garage parking — we document it in the application.
How it works
- 1
Feasibility
Structure, slab, utilities, and layout check with a firm budget range.
- 2
Design & Permits (2–4 months)
Plans, Title 24, and ministerial submittal under the 60-day state clock.
- 3
Construction (2–4 months)
Seal, frame, rough-in, insulate, finish — fast because the shell exists.
- 4
Rent It
Final inspection, address assignment, and rental pricing from our realtor team.
What it costs
| Project | Typical Range | Notes |
|---|---|---|
| Studio conversion (≈350–400 sq ft) | $125K – $170K | Kitchenette, full bath |
| 1-bedroom conversion (≈400–480 sq ft) | $150K – $220K | Full kitchen, laundry |
| Add: utility upgrades | $10K – $35K | Panel, sewer line, trenching as needed |
All-in including design and permits. Slab condition and utility distance are the main variables.
Frequently Asked Questions
How much does a garage conversion cost in the Bay Area?+
$125K–$220K all-in for most Santa Clara County conversions in 2026 — roughly half the cost of a comparable detached new-build ADU, because the foundation, walls, and roof already exist.
Do I have to replace the parking I lose?+
No. California Government Code §66314 prohibits cities from requiring replacement parking when a garage is converted to an ADU. Driveway parking remains usable, and we cite the statute directly in your permit application.
Will it hurt my home's value to lose the garage?+
Market data says the opposite when done legally: a permitted rental unit adds income-backed value that outweighs garage storage in nearly every Bay Area appraisal scenario. Where garages matter to your street's buyers, we can often site storage or a carport — your realtor-builder team will give you a straight answer for your block.
How fast can a garage conversion finish?+
Fastest legal ADU there is: 2–4 months of design/permits and 2–4 months of construction — many of our conversions collect first rent within 6–7 months of the initial call.
My slab cracks and slopes — is that a deal-breaker?+
Almost never. Sloped garage slabs get self-leveling systems or sleeper floors; typical cracking gets sealed and covered. Only major settlement requires real foundation work, and the feasibility check catches that before you commit.
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