ADU Construction, One Vetted General Contractor
An ADU packs a kitchen, a bath, and a separate living space onto a lot you already own. That is why it costs more per square foot than a full house. Local ADU rules, utility hookups, and whether it is detached, a garage conversion, or over the garage move the number as much as the floor plan. We range it by size and finish, then match you with one vetted GC.
Typical range
$98,000–$550,000
Your scope and ZIP tune this in the free estimator, no email to see it.
ADU Construction cost
ADU construction by size, 2026 national ranges.
| Scope | Typical range |
|---|---|
| Studio ADU (~400 sq ft) | $98,000–$145,000 |
| 1-bed ADU (~700 sq ft) | $170,000–$255,000 |
| 2-bed ADU (~1,000 sq ft) | $245,000–$365,000 |
Cost by material / finish
Material and finish are the other big lever, shown here at an average project size.
| Material / finish | Typical range |
|---|---|
| Standard build | $170,000–$255,000 |
| Custom / premium | $260,000–$385,000 |
What changes your price
- Square footage: studio, 1-bed, or 2-bed.
- Standard versus custom finish, and a full kitchen plus bath in a small footprint.
- Detached new-build versus garage conversion versus a unit over the garage.
- Local ADU ordinances, setbacks, parking, and utility hookups.
How it works
Describe the job
Answer a few quick questions about scope, timeline, and ZIP. Under a minute, and no email to see your number.
See your honest range
A real price range appears instantly, computed from 2026 cost data and adjusted for your project and region, with the assumptions shown.
One vetted pro calls you
Choose to be matched and a single licensed, insured, background-checked local pro reaches out.
Free instant estimate
Get your adu construction price range
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See my price range(561) 220-0117No email to see your price · One vetted pro, matched to you
ADU Construction FAQ
How much does an ADU cost?
A studio around 400 square feet starts near $98,000. A typical 1-bed standard build lands about $170,000–$255,000. A custom 2-bed around 1,000 square feet can reach $550,000. Our estimator ranges it by size and finish.
Why is an ADU more per square foot than a house?
A kitchen and a bath are the expensive rooms, and an ADU still needs both. Permits, utility laterals, and a second address on a tight lot add cost that a large house spreads over more floor.
Do I need a permit to build an ADU?
Yes. ADUs are dwellings. Zoning, setbacks, parking, and utility capacity are the usual gates. A licensed GC pulls the permit and runs inspections. Conversion of an existing garage still needs a permit.
Prefer to talk it through? Call (561) 220-0117, free, no obligation.