San Jose General Contractor for Home Additions and Remodeling
QA Builders is a licensed San Jose general contractor (CSLB #1073096) that builds home additions, kitchens, bathrooms, whole-house remodels, ADUs and custom homes for homeowners in San Jose and nearby towns, from Santa Clara, Sunnyvale, Campbell and Cupertino to Palo Alto, Los Gatos, Mountain View and Fremont. Call (669) 213-8077 for a free consultation.
Years Experience
Projects Completed
Licensed & Insured
Client Rating
We work as remodeling contractor and builder in one: we carry the project from the first walk-through to the final city inspection, including design, engineering, permits, every trade on site and the punch list at the end. Request a consultation or call the number above.
Home additions: more room without moving
Home additions come first on our list, and they are the project where a general contractor matters most, because a new room has to tie into a house that is already standing. The structure, roofline, electrical panel, plumbing and heating all have to take the new space, and the finished rooms should look as if they were always there.
We build three kinds of additions. A room addition extends the ground floor for a family room, a primary suite, a home office or a playroom. A second-story addition goes up when the lot has no room to spread out. A bump-out adds a few feet to a kitchen, bathroom or living room without a full addition.
In San Jose, two numbers decide how much paperwork an addition needs. If the house will be more than 30 feet tall or more than two stories, or its floor area ratio (floor area divided by lot area) will pass 0.45, the City requires a Single-Family House Permit from the Planning Division before it issues the building permit. We check both on your lot before design starts, so you know early which permit path you are on.
Our additions page covers home additions in San Jose type by type, the home addition cost guide explains what moves the price, and the home addition checklist lists what to settle before you sign anything. The gallery on our portfolio page shows finished room additions in San Jose, Santa Clara and San Mateo.
“The work was completed ahead of schedule, the craftsmanship is excellent, and they clearly take pride in getting things right.”
Vijay M., on a new family room and master bedroom addition (Google review)
Kitchen and bathroom remodeling
Kitchens
A kitchen remodel starts with the layout: where the sink, range and refrigerator go, how much counter sits between them, and whether a wall should come out. We draw layouts and 3D renderings so you can see the room before anything is ordered, then walk you through cabinets, counters, flooring and lighting.
The scope also decides the permit. San Jose does not require a building permit to reface or replace cabinets or to replace a countertop, but moving plumbing, adding circuits or removing a wall does. Read more about kitchen remodeling in San Jose.
Bathrooms
Our bathroom remodels range from a master bathroom remodel with a walk-in shower to a full gut renovation down to the studs, and every one depends on the parts you never see: the waterproofing behind the tile, the shower pan, venting and drains. Our portfolio includes bathrooms in San Jose (the Sunset Dr project among them), Santa Clara, Campbell, Saratoga, Cupertino and Mountain View. See bathroom remodeling in San Jose for scopes, permits and timing.
Whole-house remodels, ADUs and custom homes
Whole-house remodels
When most rooms need work, remodeling the house in planned phases usually beats a string of separate projects, because walls, wiring and plumbing are opened once. We plan the phases so you can often keep living at home. If you are still deciding whether to remodel or move, our remodel or move guide sets out the trade-offs, and the whole-house remodeling page explains the process.
ADUs and garage conversions
We build detached and attached ADUs, two-story ADUs and garage conversions. San Jose lets you design an ADU under either its own standards or the state’s, but not a mix of the two, and the choice changes the size, height and setbacks you can use. Units of 750 square feet or less pay no school or parkland impact fees there. Start with our ADU builders page or the garage conversion guide.
Custom homes and new construction
For a new house on your lot, or a teardown and rebuild, we work with architects and structural engineers and run construction from site work to move-in. Our Creek Dr project in San Jose is a complete new build, with 42 photos in the project gallery. More on custom home building.
How a QA Builders project runs
- Consultation and walk-through. We visit the house, measure, and talk through what you want and what you want to spend. Contact us for a free consultation and estimate.
- Design and engineering. Layouts and 3D renderings for interiors; for structural work, we collaborate with top architects and engineers. San Jose accepts plans drawn by anyone for conventional wood-frame additions and remodels to one- and two-story homes, but any part that departs from conventional framing must be designed, stamped and signed by a licensed architect or engineer.
- Permits. We navigate San Jose’s permitting process on your behalf, handling all paperwork and inspections. Small projects on one-story homes (an addition under 500 square feet, a remodel of 750 square feet or less, no load-bearing walls touched) can qualify for the City’s over-the-counter service; larger or structural work goes through standard plan review.
- Construction with one point of contact. Every project receives a dedicated project manager so you know who to turn to every step of the way.
- Inspection and handover. City final inspection, then final walk-through, punch list completion, and our comprehensive warranty.
Our team employs the most innovative technology to stay ahead on your timeline, budget and overall outcome. Our engagement goes way beyond project completion. We maintain close relationships with each of our clients.
“The first point that set QA Builders apart from the others was that they sent the project manager instead of an estimator.”
Hyung-Suk K., on a townhouse kitchen renovation and new flooring (Google review)
Licensed, bonded and insured
QA Builders is Q A Builders Inc, a California Class B General Building contractor. As of October 2026, the state license board record for CSLB License #1073096 shows the license as current and active, a $25,000 contractor’s bond, and workers’ compensation insurance on file with the state board.
You can check any contractor yourself, and it is worth doing for each of the remodeling and construction companies you compare in San Jose: enter the license number on the California Contractors State License Board’s license check and confirm the name, status, bond and insurance. California also requires contractors to show their license number in advertising, so an ad without one is worth a question. Our guide on how to choose a remodeling contractor lists the other checks worth making.
Certified
Fully licensed & insured company for your residential project.
Experience
Over 500+ remodeling projects and new construction builds.
Honorable
Clear, honest communication and high quality work at our core.
Reliable
Happy customers and a long list of referrals showcase our results.
What clients say
QA Builders holds a 5.0 average from 47 Google reviews (Google Business Profile, October 2026). Clients name the people they worked with: Sal, the owner; Josh and Poli, who run projects; and Walter, who leads construction on site.
“The project was completed on time and within budget, and the quality of the workmanship and finishing exceeded our expectations.”
Nithin V., on two bathroom remodels, flooring and painting (Google review)
Watch clients walk through their finished projects on our video testimonials page.
Where we work
We take projects across three counties. In Santa Clara County: San Jose (including Willow Glen), Santa Clara, Sunnyvale, Campbell, Saratoga, Palo Alto, Los Gatos, Mountain View, Milpitas and Cupertino. In San Mateo County: East Palo Alto, Redwood City, San Carlos and San Mateo. In Alameda County: Fremont, Newark and Union City.
Questions homeowners ask a general contractor
What does a general contractor do on a remodel or addition?
A general contractor takes responsibility for the whole job: it prices the work, coordinates the designer and engineer, pulls the permits, schedules every trade, books the city inspections and answers to you for the result. Without one, you become the person who sequences the framer, plumber, electrician and drywall crew and fixes the gaps between them.
How much does a remodel or addition cost in San Jose?
Our service pages publish these ranges:
- Home additions: costs typically range from $200-$400 per square foot depending on complexity, materials, and whether structural work is needed.
- Kitchens: a typical Bay Area kitchen remodel ranges from $30,000 to $100,000+.
- Bathrooms: bathroom remodel costs range from $15,000 to $50,000+ depending on scope, materials, and size.
- ADUs: ADU costs typically range from $150,000 to $350,000+ depending on size, type, and finishes.
Where your project falls depends on its size, whether the structure changes, how far plumbing and electrical move, the finishes you choose, and what the permit path requires. We price each project after the walk-through. Our cost guides for additions, kitchens, bathrooms and ADUs explain each cost driver.
Do I need a permit for my project?
In San Jose, cosmetic work such as paint, new flooring, new countertops and cabinet replacement needs no building permit. New construction, additions, structural changes, demolitions and most plumbing, electrical and mechanical work do. The City notes that unpermitted work has to be disclosed when you sell, and insurance generally will not cover damage tied to it.
Contact Our Team
Talk to us about your project
Call (669) 213-8077 (Mon-Fri 8AM-6PM, Sat 9AM-3PM), email Contact@qabuilders.com, or send the form on our contact page. One of our representatives will get back to you promptly with a free quote.
QA Builders, 1917 Creek Drive, San Jose, CA 95125.