ADU models,
floor plans and prices in California
Backyard Studio
Open studio · 8' × 15' · with deck
Your office, 30 steps from the kitchen.
Configurations
Open Floor Plan · En Suite Half Bathroom
All-in price
$75,900
✓ Permits to keys — everything included
Best forOffice · gym · studio
Small Studio
256 sq ft · 1 bed · 1 bath · no deck
The most rent per dollar we build.
Included
Laundry room
All-in price
$124,900
✓ Permits to keys — everything included
Estimated rent**$1,900–2,700/mo
Large Studio ADU
320 sq ft · Studio · 1 bath · 1 laundry
A studio with its own deck.
Included
64 sq ft deck · Laundry room
All-in price
$154,900
✓ Permits to keys — everything included
Estimated rent**$2,000–2,800/mo
1 Bedroom ADU
480 sq ft · 1 Bedroom · 1 bath
A real bedroom door. Rent it or keep family close.
Included
96 sq ft deck · Laundry room
All-in price
$214,900
✓ Permits to keys — everything included
Estimated rent**$2,100–3,000/mo
2 Bedroom ADU
640 sq ft · 2 Bedrooms · 1 bath
Room for family, under one roof of your own.
Included
128 sq ft deck · Laundry room
All-in price
$271,900
✓ Permits to keys — everything included
Estimated rent**$2,600–3,600/mo
Custom Project
Custom size · Custom layout
Included
Everything you could ever imagine
You pick the number of dollar signs
$ to $$$$
Accessible ADU
Designed for accessible living
Included
Roll-in curbless shower
Grab bars throughout
Fold-down shower seat
Roll-under sink
Wide doorways
Lever door handles
Building price
On request
Which Model Is Right for You?
Home Office or Studio
Create a dedicated workspace separate from your main home
Guest House
A compact and comfortable space for hosting family and friends
Rental Income
Maximize your property's potential with a home designed for long-term or short-term rental
Family Living
Spacious layouts designed for everyday comfort and growing families
Compared ADU models
or school feesNo impact
or school feesNo impact
or school feesIncluded
in the price
* ADUs under 750 sq ft pay no impact fees; under 500 sq ft, no school fees (Cal. Gov. Code § 66311.5, Ed. Code § 17620). For the 2 Bedroom ADU, school fees are included in the all-in price.
** Based on HUD Fair Market Rents FY2026 (studio / 1 BR / 2 BR) for major California metros, adjusted ±4–5% for studio size. Actual rent depends on location, layout and finishes.
*** All-in price: design, permits and city fees, foundation, delivery, crane, utility hook-ups and final inspection. Confirmed in writing after a free lot check, before you sign. Launch pricing: 30% off our published home prices, through December 31, 2026.
Additional parameters
Construction
Steel modular, factory-built in our Lathrop, CA factory
Approval
California HCD-approved plans (HCD #1585366)
Project time
4–6 months from signing to keys
Delivery & installation
Delivered in a day, installed in 1 week
On-site work
Minimal — foundation, utility connections and final inspection
What’s included
Foundation, permits, delivery, crane, utility hook-ups and final inspection
Process
Choose
Select the model
that best fits your needs
Customize
Find the right size and layout for your needs
Review
We verify site requirements and local regulations
Ready to start?
Start with Bay Modular
Submit your information and our team will get back
to you about next steps
Common questions
How big can an ADU be in California?
Cities set their own limits, and every model here is comfortably under all of them — the largest is 640 sq ft. Size is rarely what stops a project; setbacks and crane access usually decide what fits.
Do they have a real kitchen and bathroom?
Yes. Every model from the Small Studio up has a full-size kitchen, laundry and a full bathroom with a real shower, not a stall. The Backyard Studio is an open studio with an en-suite half bathroom.
Which models have a separate bedroom?
The 1 Bedroom ADU (480 sq ft) has one private bedroom and the 2 Bedroom ADU (640 sq ft) has two. The studios are open-plan, with the bed in the main room.
What's the difference between the Small Studio and the Large Studio?
Space and the deck. The Small Studio is 256 sq ft with no deck; the Large Studio ADU is 320 sq ft and comes with a 64 sq ft deck. Both have a kitchen, laundry and a full bathroom.
Do ADUs get their own address?
Usually, yes. Most California cities give an ADU its own unit number on your street address, so it can receive mail and deliveries. Your city confirms this during permitting.
Can I change the floor plan?
Our standard plans are pre-approved, which is what keeps permitting fast, and you choose the finishes. If you need a different layout, the Custom Project is designed around you and goes through city approval.