ADU Constructionin Northern California
An ADU is the best construction value in California right now: state law forced cities to approve them, and a well-built unit adds rental income or family housing on land you already own. We design and build detached ADUs, attached units, and garage conversions across the Central Valley and East Bay.
Licensed & Insured · CSLB #1130548 · 5.0★ on Google, Yelp, Thumbtack & Angi
The Work
Done Right, Documented, and Inspected
We handle the whole path — plans, city submittal, utilities, construction, and final — and we quote real numbers up front, because ADU budgets blown by surprise utility work are how this industry got its reputation.
Every project runs under Sarmento Bros. Construction Inc. — CSLB #1130548, fully insured with general liability and workers' compensation. Based in Manteca, we serve businesses and property owners across the Central Valley, East Bay, and greater Northern California.
What We Handle
- ✓ Detached new-construction ADUs
- ✓ Garage conversions and attached units
- ✓ Plans, engineering, and city permitting
- ✓ Utility connections and upgrades
- ✓ Full interior finish — kitchen, bath, laundry
- ✓ Site work, driveways, and separate entrances
How It Works
A Straightforward Process
01
Walk & Scope
We meet at your space, listen to what you need, and scope the job honestly — including the parts other bids leave out.
02
Fixed Estimate
A written, itemized estimate with a real schedule. Free, and good numbers — not a teaser that grows later.
03
Permits & Build
We handle drawings, permits, and inspections, then build with our own crews and trusted trade partners.
04
Walkthrough & Closeout
Final walkthrough together, punch list closed, documents handed over. Done means done.
Common Questions
ADU Construction FAQs
How much does an ADU cost to build?+
Garage conversions generally start well below detached units; detached ADUs vary with size and utility distance. We give fixed, itemized quotes after a site visit — free — so you're comparing real numbers, not internet averages.
How long does the whole process take?+
Design and permits typically run 2–4 months depending on the city; construction 4–6 months for a detached unit, less for conversions. We give you the timeline in writing for your specific city.
Will the city actually approve it?+
California law requires cities to approve ADUs meeting state standards, and most local resistance is gone. We know the requirements in Manteca, Tracy, Stockton, Modesto, and the surrounding cities because we build in them.