Wells & Company Builders, a Bay Area general contractor since 1998, now builds ADUs using city pre-approved plans. One local team handles permits, construction and move-in, for a fixed price and a firm timeline. Want something one of a kind? We build custom too.
An accessory dwelling unit is a small, complete home on your lot, with its own kitchen, bath and entrance. Bay Area homeowners build them for family, for income and for the long run.
Give aging parents, adult kids or a caregiver their own front door, steps from yours. Everyone keeps their privacy and nobody leaves the neighborhood.
A backyard unit can help cover a mortgage, fund retirement or pay for itself over time in one of the country's tightest rental markets.
Extra permitted living space makes your property more useful and more flexible for whoever owns it next.
CA median appraisal, 2023: $1.06M with an ADU vs $715K without (FHFA)Move into the smaller house and rent or hand off the main one. Stay in the community you know without the upkeep of a big home.
California now requires every city to offer pre-approved ADU plans and to approve or deny a qualifying detached ADU within 30 days.
State law AB 1332, in effect since Jan 1, 2025ADUs are now about one in four new homes permitted in California. Each one adds a home without changing the character of the street.
26% of CA housing units permitted in 2025 (HCD data)You never have to manage an architect, a permit desk and a crew separately. We run every step and keep you posted.
Tell us your address. We look at lot size, setbacks, utilities and what your city allows.
We walk the property with you and give you one price in writing, with site conditions spelled out.
Pick a city pre-approved plan and a finish package, or start a custom design with us.
We prepare and file everything. Pre-approved plans take the city's fastest review path.
Foundation to finishes with our local crew, plus weekly photo updates so you always know where things stand.
Final inspection, certificate of occupancy and a walkthrough. Your keys and a care guide on handover day.
Construction typically takes about 12 weeks. Pre-construction time (design and permits) varies by city, and we'll give you a schedule for your project at the site visit.
A one-bedroom backyard house sized for real life, with room for a parent, a renter or a home office.
Rendering
Open living and kitchen on one side, a quiet bedroom and bath on the other, with its own entry and patio.
Will it fit? State law caps side and rear setbacks for a detached ADU at 4 feet, so a 20' × 30' house fits behind many Bay Area homes. Our free feasibility check confirms it for your lot.
Most clients choose a pre-approved plan for speed and price certainty. If your lot or your vision calls for something unique, we design and build custom.
A city pre-approved plan, built start to finish for a fixed package price.
Roughly $300 per sq ft, depending on finishes and design. Site work quoted after your visit.
The same fast path, with upgraded finishes and layout tweaks your city allows.
Roughly $300 per sq ft, depending on finishes and design.
A design made for your site and the way you live, for tricky lots, larger units or a specific look.
Quoted after design consultation.
Your package price is fixed in writing. Site conditions are identified up front, not discovered halfway through.
We publish timelines and track every project against them, so you can plan a move-in date or a lease start.
Design, permits and construction under one agreement and one point of contact.
Pre-approved doesn't mean cookie-cutter. Every joint, finish and fixture is installed by a local crew with 30 years of custom building behind it.
We know each city's program, fees and review times, and we use them to save you months.
Weekly photo updates, a walkthrough at each milestone, and a say in every decision from concept to completion.
Founder, Wells & Company Builders
Garth has spent 30 years building homes. He worked his way up from apprentice carpenter to superintendent project manager, then founded Wells & Company Builders in 1998. His crews are known for the details most people never see: how joints come together, how materials are installed to show them at their best, the last coat of paint. Our ADU program brings that craftsmanship to backyard homes, with a straight price, a real schedule and someone accountable from start to finish.
He sees backyard homes as one of the fastest ways to add homes where people already want to live, and as a way for families to stay in the communities they love.
“Building is more than following drawings and meeting code. It’s about bringing your vision to life, down to the last brush stroke.”
Reviews from Wells & Company Builders clients on remodels and other projects.
“I cannot recommend Garth more highly. He was such a nice guy and did a wonderful job for us.”
“The high quality of workmanship and attention to clean up impressed me.”
“Garth was prompt courteous and did exactly what he said he will do.”
We focus on cities with strong pre-approved ADU programs, so your project moves quickly, and we build custom wherever a site calls for it. Don't see your city? Ask us anyway.
Every city runs its ADU program a little differently. These official and nonprofit resources explain the local rules, fees and pre-approved plans. When you're ready to see what fits your lot, we'll take it from there.
A step-by-step guide and a "Can I build an ADU?" map that shows which rules apply to your address. Covers Alameda, Berkeley, Oakland, Fremont, Hayward, San Leandro, the Tri-Valley and unincorporated areas.
Permit-ready studio, one- and two-bedroom plans you can adapt to your lot, plus Oakland's ADU categories and permit steps.
Nine preapproved plans from six designers, 496 to 1,000 sq ft. Reviewed in 7 business days for a $1,000 flat plan review fee.
A gallery of pre-approved designs. Plan check fees are cut to 50% when you use one.
Pre-approved plan sets from local architects and designers, marked in the city's ADU Plans Gallery.
A program to speed permits for new detached ADUs. Check the page for the current plan list.
Third-party plans pre-approved by the city. Standard plan check fees are waived; a short site-plan review still applies.
Pre-approval for unincorporated Contra Costa, plus building review for Lafayette, Moraga, Orinda, Clayton and Hercules.
Building in the East Bay? We know these programs and file the permits for you.
Free feasibility checkA partnership of the County and Marin cities and towns. Step-by-step guide, floor plans, a cost and rent calculator, and homeowner stories.
Free one-hour feasibility consultations, technical help by phone and email, and pre-approved plans. Serves Marin, Sonoma and Napa.
Permit fee waivers for ADUs in unincorporated Marin, a program to legalize existing units, and planning contacts.
How the city's pre-approved program works for detached ADUs. Plans are added as they are approved.
Building in Marin? We can tell you which fee waivers and plans apply to your lot.
Free feasibility checkPre-reviewed ADU plans for unincorporated Sonoma County. Permit review is targeted at 30 days, compared with about 60 for a standard ADU.
Started in Sonoma and Napa. Free feasibility consultations, technical help and pre-approved plans.
Seven pre-reviewed plans from 615 to 1,175 sq ft, with reduced plan check fees.
Pre-reviewed detached ADU plans to shorten the city's permit review.
Building in Sonoma County? Garth is based in Santa Rosa, right where you're building.
Free feasibility checkThe state housing department's plain-language guide to ADU law, updated March 2026. Covers size limits, setbacks, fees and rentals.
Since January 2025, every California city must offer pre-approved ADU plans and decide qualifying applications within 30 days.
State law is on your side. We turn it into a schedule and a fixed price.
Free feasibility checkLinks checked October 2026. Programs change often; confirm details with your city.
It's a backyard home design your city has already reviewed for code. Because the design is pre-checked, the city mainly reviews how it sits on your lot, which shortens permitting. California requires every city to offer these plans.
It depends on size, finishes and your site. Our pre-approved plans run roughly $300 per sq ft. We give you a fixed price after a free site visit, with site work like utility trenching spelled out separately.
Pre-approved plans move through permitting faster than custom designs. We'll give you a written schedule at the site visit and send weekly updates during construction.
Most single-family lots in the Bay Area can fit an ADU under state law. Our free feasibility check looks at size, setbacks, slope and utilities before you commit to anything.
Yes. ADUs can be rented long-term in California. Some cities set a minimum rental period, which we'll flag for your city.
Many owners use a home equity line, a cash-out refinance or a renovation loan. We can introduce you to lenders who finance ADUs, and point you to any local incentive programs your city offers.
Start with a no-pressure call or request an estimate. We'll tell you what your city allows and what your options cost.
Talk through your goals and your lot with Garth. No prep needed.
Share your address and what you're picturing. We'll follow up within 1 business day to schedule a site visit.
