How much does an ADU cost to build in Sacramento?
Building an Accessory Dwelling Unit (ADU) in Sacramento costs $150,000 to $350,000+ depending on size, type, and finishes.
Cost ranges by type: Garage conversion: $80,000 $150,000 Interior conversion (basement/attic): $50,000 $120,000 Detached new construction (400 800 sq ft): $150,000 $300,000 Attached addition: $120,000 $250,000 Prefab/modular ADU: $100,000 $200,000 (plus site work)
Per square foot costs in Sacramento: Budget: $200 $300/sq ft Mid range: $300 $400/sq ft High end: $400 $500+/sq ft
Sacramento ADU rules (as of 2026): Maximum size: 1,200 sq ft for detached, 50% of primary home for attached No owner occupancy requirement (you can rent both units) No parking requirement if within half mile of public transit Setback: 4 feet from rear and side property lines Sacramento has streamlined permitting for ADUs Impact fees waived for ADUs under 750 sq ft
Timeline: Plan for 6 12 months from design to completion. Permitting alone takes 4 8 weeks in Sacramento.
Financing: Home equity loans, construction loans, or California Housing Finance Agency ADU grant program (up to $40,000 for qualifying homeowners).
This information is provided as a general guide for Sacramento area homeowners. Actual costs and requirements may vary based on your specific situation. Always verify contractor licenses at cslb.ca.gov and check with your local building department for current permit requirements.