How Much Does an ADU Cost?
Get an instant, city-specific estimate for your Accessory Dwelling Unit. Our calculator uses real permit fees and local contractor rates.
Why Use Our ADU Calculator?
City-Specific Data
Real permit fees and labor rates for your specific city, not national averages.
Updated Regularly
Our cost data is updated quarterly with the latest construction prices and permit fees.
Comprehensive
Covers all ADU types: detached, attached, garage conversion, JADU, and basement.
Frequently Asked Questions
How accurate are these cost estimates?
Our estimates are based on real construction data and updated quarterly. They should be within ±15% of actual costs for most projects, but final costs depend on specific site conditions and contractor selection.
Are permit fees included in the estimate?
Yes, our estimates include typical permit fees, plan check fees, and impact fees where applicable. However, some cities have unique requirements that may add additional costs.
What's not included in these estimates?
Site-specific costs like utility connections, significant grading, or structural upgrades to existing buildings are not included. These can add $5,000-$25,000+ depending on your property.
Can I save or share my estimate?
Yes! Use the "Get Free Contractor Quotes" button to save your estimate and receive it via email along with qualified contractor contacts in your area.