ADU design
ADU floor plans: layouts by size and bedroom count
By the HyreADU research desk. Last checked .
The short answer
ADU floor plans fall into three common layouts: a studio with one main room, a 1-bedroom with a separate bedroom, and a 2-bedroom.
California agencies’ own plan sets show the range: Sacramento’s Shelf Ready plans are 367 sq ft (studio), 559 (1-bedroom) and 747 (2-bedroom); Anaheim’s run from a 224 sq ft studio to a 1,199 sq ft 3-bedroom.
| Layout | Agency plan sizes (sq ft) | Source |
|---|---|---|
| Studio | 224 (Anaheim), 340 (Fresno), 367 (Sacramento), 425 (Santa Cruz County) | Each agency’s plan page |
| 1-bedroom | 455 (Los Angeles YOU-ADU), 499 (Fresno, Anaheim), 559 (Sacramento), 637 (Santa Cruz County) | Each agency’s plan page |
| 2-bedroom | 747 (Sacramento), 800 (Santa Clara County), 990 (Anaheim), 998 (Santa Cruz County) | Each agency’s plan page |
| 3-bedroom | 1,015 (Fresno), 1,199 (Anaheim), 1,200 (Santa Clara County) | Each agency’s plan page |
How a good ADU layout works
A good ADU layout puts the entry into the living space, keeps the kitchen along one wall, and gives the bedroom a window on a different side from the main house.
The bathroom sits next to the kitchen so plumbing runs stay short. Storage is planned, not found. Our ADU design hub covers light, storage and privacy.
Size and the 750 square foot line
Size has a fee consequence in California. No impact fee may be charged on an ADU of 750 square feet or less of interior livable space, and above that the fees must be proportional to the main house (Gov. Code § 66311.5).
Several agency 2-bedroom plans sit just under the line, such as Sacramento’s at 747 and Placer County’s at 746 and 749.
Choosing by household
One person usually fits a studio; a couple or a tenant who works from home suits a 1-bedroom; a family or two adults sharing need two bedrooms. Compare on studio vs 1-bedroom, and see the size-specific pages for studio, 1-bedroom and 2-bedroom plans.
A mistake to avoid
The mistake to avoid is comparing plans by total square feet alone. Two plans of the same size can feel very different depending on ceiling height, window placement and how much area is lost to hallways. Ask for the net room sizes and walk the plan in your head from the front door.
What to do next: check your lot with the ADU feasibility checker, read the questions to ask an ADU builder, then tell us about your project. Matching is not live yet, so we reply with information, not a quote.
Get ADU optionsQuestions
What is the most common ADU size?
Our ADU size research covers what permits show. Plan sizes above are examples, not averages.
Can I change a pre-approved floor plan?
Many programs bar or limit changes; Anaheim’s Express track does not allow them.
Do floor plans include electrical and plumbing?
Construction sets do. A marketing floor plan does not.
How big can my ADU be?
See ADU size for the state floors and local caps.
Sources
- City of Sacramento, Preapproved ADUs and Shelf Ready ADU Plans. Checked September 5, 2026.
- City of Anaheim, Pre-Approved Plan Catalogue. Checked September 5, 2026.
- City of Fresno, ADU and Small Homes Program. Checked September 5, 2026.
- LADBS, ADU Standard Plan Program. Checked September 5, 2026.
- County of Santa Cruz, Pre-Designed ADU Plans. Checked September 5, 2026.
- Gov. Code § 66311.5 (ADU impact fees, connection fees and capacity charges). Checked September 5, 2026.
- HyreADU research: pre-approved ADU plans in California. Checked September 5, 2026.
HyreADU is a publisher. It does not design, permit or build ADUs, has no partner builders, and gives no legal, tax, lending or engineering advice.
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