What is an ADU (Accessory Dwelling Unit)?

An ADU (Accessory Dwelling Unit) is a secondary housing unit on a single-family residential lot. Also called a granny flat, backyard cottage, in-law suite, or garage conversion. ADUs can generate rental income of $1,200–$2,500/month.

Do I need permit-ready plans for an ADU?

Yes — to build an ADU legally, you need permit-ready (PE-stamped) engineering plans accepted by your local building department. QuiPlans provides PE-stamped structural drawings prepared by licensed engineers in 26 U.S. states.

How much does it cost to build an ADU?

ADU construction costs typically range from $80,000 to $300,000+ depending on size, location, and finishes. A studio ADU (400 sq ft) typically costs $80K–$140K. A 2-bedroom ADU (750 sq ft) typically costs $150K–$250K.

How long does it take to get permit-ready ADU plans?

QuiPlans delivers PE-stamped permit-ready plans in 10–14 business days. Instant downloadable architectural drawings are available immediately after purchase.

Which states do QuiPlans engineers work in?

QuiPlans licensed engineers cover 26 U.S. states including California, Texas, Florida, Colorado, Arizona, Georgia, Nevada, Washington, Oregon, Illinois, and more.

QuiPlans

Professional floor plans and permit-ready engineering services trusted by builders nationwide.