An independent guide to building an ADU in the Bay Area
Bay Area ADU Builders helps homeowners check what their city allows, what it charges, and which licensed builders work there, before anyone asks for a quote.
How the site works
Rules and fees come from the city
Every rule and fee on a city page links to that city’s own ADU page, fee schedule or fee estimator, with the date we read it. If a city doesn’t publish a number, we say so.
Builders are ranked by a public score
The score uses the state license record and what the builder publishes on its own site. The parts and point values are on the methodology page.
Nobody pays to rank
A paid spot is labelled Sponsored and sits in its own box. It never moves the ranked list.
Partner means leads go there
We show a Partner label only on pages where requests from this site go to that builder.
Who writes it
The Bay Area ADU Builders editorial team writes and checks every page. We read city and state sources, check licenses with the Contractors State License Board (CSLB), and read each builder’s own site. When a fact is wrong, we fix it and update the check date.
What we are not
- We are not a contractor, architect, engineer or permit office.
- We can’t promise permit approval, a price, a timeline or that a builder is right for your lot.
- We don’t publish reviews or ratings we can’t verify, and we don’t copy them from other sites.
- Our cost numbers are estimates, labelled as ours and kept apart from official fees.
Where to start
Pick your city to see the rules and fees, then read the builders who work there. The methodology page shows exactly how the score works.
Want quotes from licensed builders?
Tell us your city, the type of ADU and your budget range. Requests go through a Makeform form.