ADU basics in CaliforniaComing soon
Detached, attached, conversion, JADU — what each type means and which state rules protect your right to build.
Free ADU feasibility check · California
Can you build an ADU on your California lot?
Enter your address. We check your city's zoning rules against your parcel and show you what you can build — in minutes, not weeks.
Free · No card · Get your property-specific ADU report in 90 seconds.
What could fit in your backyard
Real ADU types our designers work with every day. Your report shows which of these your lot supports.
How it works
— 01Enter your address
We pull your parcel dimensions, zoning district, and the ADU rules your city actually enforces.
— 02Answer a few questions
Existing garage? Unpermitted shed? Sloped yard? Two minutes, plain-English questions.
— 03Get your free report
A site diagram of your buildable area, the zoning math, and what to watch out for — free.
ADU rules by city — free
Plain-English summaries of each city's ADU regulations, reviewed by our designers and kept current. Start with your city, then check what the rules mean for your specific lot.
#1Los AngelesLos Angeles CountyADU rules#2San DiegoSan Diego CountyADU rules#3San JoseSanta Clara CountyADU rules#4San FranciscoSan Francisco CountyADU rules#5OaklandAlameda CountyADU rules#6SacramentoSacramento CountyADU rules#7Long BeachLos Angeles CountyADU rules#8AnaheimOrange CountyADU rules
These are the current top 8 cities from our reviewed California ADU rule set. Don't see yours? Run a property check — state ADU law applies everywhere.
A real feasibility report, not a chatbot guess
Any AI can tell you ADUs are "usually allowed." Your free HomeFeasible report runs the actual numbers for your parcel and your city, the same way our engineers start a paid consultation.
- Setbacks, height, and lot coverage calculated from your city's ordinance — not estimated by a chatbot
- A to-scale site diagram showing exactly where an ADU can sit on your lot
- Permit and design risk notes written by California structural designers
- A formal report you can share with your contractor, agent, or lender
Learn the rules before you build
Free guides written by working designers — the context behind the regulations, without the legalese.
SB 9 explainedComing soon
How the lot-split law actually works, who qualifies as an urban lot, and why most applications stall.
Garage conversion guideComing soon
The fastest, cheapest path to an ADU — grandfathered setbacks, no replacement parking, real cost ranges.
Common questions
Straight answers about ADUs, SB 9, and what a feasibility check actually tells you.
On most single-family lots, yes — state law guarantees the right to build at least an 800 sq ft ADU with 4 ft side and rear setbacks on qualifying lots. The real question is what your specific parcel allows: lot shape, existing structures, easements, and slopes determine the size and placement. That's what a feasibility check answers.
State law protects at least 800 sq ft. Most cities allow detached ADUs up to 1,200 sq ft if your lot can fit one within setbacks and lot coverage limits. Your buildable envelope — not the ordinance ceiling — usually decides the practical maximum.
Often not. Parking is waived within half a mile walking distance of public transit, for garage conversions, and in several other cases. Many Bay Area properties qualify for at least one exemption.
SB 9 lets owners of single-family lots in urbanized areas split the lot or add a second primary home. Qualification depends on lot size, location, tenant history, and other criteria — it's more restrictive in practice than headlines suggest.
Yes. Real estate agents run checks to show buyers a listing's ADU potential, and contractors use them to understand a site before bidding. The free report doesn't require the owner's involvement, and you can share the PDF directly with your client.
The initial report is free: feasibility verdict, site diagram, and the zoning math for your parcel. A full engineer-reviewed report with risk assessment, cost ranges, and timeline will be a fraction of the thousands a traditional consultation costs.
No. We give you a preliminary, parcel-specific assessment based on current regulations — the same starting point an engineer uses. Final approval always comes from your city's planning and building departments.
Know what your lot allows — before you hire a designer, engineer, or contractor.
Homeowners use it to plan. Agents use it to show a listing's potential. Contractors use it to scope a bid. The report is free either way.