Garage conversion ADU floor plans
A 2-car garage (about 20 by 20 ft) converts to a 1 bedroom ADU of about 380 sq ft inside the walls. A 3-car garage gives about 570 sq ft, enough for a bigger living room or a second bedroom. The garage's walls set the size, so the layout works inside them.
2-car garage conversion, 1 bedroom
| Kitchen | 8'-6" x 7'-6" |
|---|---|
| Bath | 6' x 7'-6" |
| Laundry closet | 5' x 7'-6" |
| Living | 10' x 12' |
| Bedroom | 9'-6" x 12' |
$95K to $155K estimated build cost in Sacramento. Add your ZIP in the editor for your area.
More floor plans to start from
3-car garage conversion, 1 bedroom
$134K to $218K estimated build cost in Sacramento. Add your ZIP in the editor for your area.
Why convert the garage
The walls, roof and slab are already there, so a conversion usually costs far less than a new detached ADU. In California, an existing garage converted to an ADU needs no new setback, and the city can't require you to replace the lost parking.
The work is in what you can't see: a slab that may need a moisture barrier, insulation, new windows and an egress window for the bedroom, and plumbing runs to the bath and kitchen.
Will it fit your lot?
For homes in the California areas we cover, the free lot check reads your parcel, setbacks and local rules and shows the biggest unit that fits.
Check your lotQuestions
Can a 2-car garage be a 1 bedroom ADU?
Yes. About 380 sq ft inside the walls fits a bedroom of about 9.5 by 12 ft, a full bath, a laundry closet and a kitchen run beside the living room.
Do I have to replace the parking?
Not in California: when a garage is converted to an ADU, the city can't require the parking to be replaced (Gov. Code 66314(d)(11)).
Last checked 2026-11-02. Costs are estimates priced at ZIP 95818, not bids. Floor plans are concept layouts; a licensed designer or architect prepares the plans your city approves.