Can you build an ADU on your property? Check instantly.
Find out if your lot qualifies for an accessory dwelling unit — zoning, lot size, and state law checked in seconds.
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Frequently Asked Questions
Can I build an ADU on my property?+
Enter your address above for a free instant check. ADU eligibility depends on your zoning designation, lot size, state law, and local ordinances. Several states (California, Oregon, Washington, Colorado, Vermont, Maine, Connecticut) now require municipalities to allow ADUs.
What is an ADU?+
An ADU (Accessory Dwelling Unit) is a secondary housing unit on a single-family lot. ADUs include detached backyard cottages, garage conversions, basement apartments, and above-garage units. They are typically 400-1,200 sqft.
How much does an ADU cost to build?+
ADU construction costs typically range from $100,000-$300,000 depending on size, type (detached vs conversion), location, and finishes. Detached new construction ADUs average $150-$250 per sqft. Garage conversions are typically $75,000-$150,000.
Do I need a permit to build an ADU?+
Yes. ADUs require building permits in virtually all jurisdictions. In states with statewide ADU mandates (CA, OR, WA, etc.), permits must be processed within 60 days. ReadyPermit estimates your permit timeline as part of the full Buildability Report.