Find Trusted Garage Conversion Contractors in California
We match you with pre-screened, local pros so you can build with confidence.
Trusted by homeowners across California
GreatBuildz helps homeowners find trusted garage conversion contractors across California. We started in Los Angeles and now cover Orange County, Ventura County, San Diego, the Inland Empire, and the Bay Area.
The perfect contractor in 3 easy steps
Why Homeowners Choose GreatBuildz
It’s free for homeowners.
Using GreatBuildz is completely free for homeowners. No fees, no obligation, and we never sell your information.
We actually vet our contractors.
Every contractor passes a 10-point screening: licensing, insurance, background, references, and more. Fewer than 5% make it into our network.
You get a dedicated remodeling advisor.
A real person stays in your corner from day one, helping you compare bids, answer questions, and keep your project moving. Most homeowners say it’s the part they didn’t know they needed.
We hold contractors accountable.
Our reputation rides on every match we make. We stay involved through the whole project and stand behind every contractor in our network.
Garage Conversion Basics
What You Can Turn Your Garage Into
A garage is the cheapest square footage you will ever add, because the slab, walls, and roof are already there. How far you take it decides your permits, your timeline, and your budget.
Our guides to office conversions, studio apartments, and garage bedrooms cover the smaller projects in detail.
Finished Room
A home office, gym, music studio, or extra bedroom. Insulation, drywall, flooring, electrical, and climate control, with little or no new plumbing. It still needs permits, but it is not an ADU and it costs far less than one.
Studio or Guest Suite
A smaller independent space with a bathroom, a compact kitchen, and its own entrance. Once it has a kitchen and a private entry it follows the ADU permit path, at a smaller scope than a full build.
Full Garage ADU
A complete living unit with a full kitchen, bathroom, and private entrance that you can rent out, house family in, or hold for long-term property value. This is what most homeowners come to us for.
Garage Conversion Costs
How Much a Garage Conversion Costs in California
A garage conversion is the most affordable way to add a full living unit to your property, because the structure, slab, and roof already exist. Most garage conversion ADUs in California run $120,000 to $150,000 with standard finishes, plus $8,000 to $15,000 for design and plans.
Upgraded finishes and systems push projects to $150,000 to $200,000, and large or premium conversions can top $200,000. Wherever you land, smart budgeting includes a 10 to 15 percent contingency for surprises.
The garage itself decides a big share of the number. Slab condition, ceiling height, and how far the garage sits from your utility lines swing the price more than finishes do. A simpler conversion without a kitchen or bathroom, like an office or gym, costs far less because there's little or no new plumbing.
Basic Garage ADUStandard finishes, layout as-is
Upgraded Finishes & SystemsBetter materials, electrical, HVAC
Large or Premium ConversionExpanded scope or high-end build
One honest piece of advice: the cheapest bid is rarely the best choice.
A quote that comes in far below the others often means an incomplete scope, lower-grade materials, or change orders that show up later. We help you compare bids on equal terms so you can tell the difference.
Ready to convert your garage?
Tell us about your project and we’ll connect you with three vetted local contractors. It’s free, with no obligation.
Timeline & Permits
Garage Conversion Timeline, Permits, and Unpermitted Conversions
How Long a Garage Conversion Takes
A garage conversion ADU typically takes 5 to 6 months from start to finish. Design, plans, and city approvals usually take about 3 months, and construction runs another 2 to 3 months once permits are in hand. Simpler conversions without plumbing move faster, and a slow plan-check desk can stretch the front end, so where you build matters.
Design, Plans & City Approvals
Construction
Start to Finish
Permits and the Laws on Your Side
Every garage conversion needs permits through your city's building department (LADBS in the City of Los Angeles). The good news is that California's ADU laws clear most of the old roadblocks:
- A conversion with a kitchen and bathroom counts as an ADU, so it gets streamlined approval: no planning board hearings, no neighbor sign-off
- There's no minimum lot size, so almost any residential property qualifies
- Existing garages that don't meet today's setback rules can often be grandfathered in as they stand
- No parking spot is required for the ADU if you're within half a mile of public transit
- Your HOA can't prohibit an ADU conversion (California law AB 670)
Good to Know
In California, a contractor can’t legally ask for a down payment of more than
Of the contract price, whichever is less
A licensed general contractor will pull the permits as part of the job, and every contractor in our network is licensed, bonded, and insured.
Already Have an Unpermitted Conversion?
You're far from alone; LA is full of them. Leaving it unpermitted risks fines, forced restoration, insurance denial, and trouble when you sell. Legalizing it usually means new plans ($4,000 to $12,000) showing the space meets code, city approval, and construction to bring it up to standard ($20,000 to $70,000 in most cases). If the unit was built before January 1, 2020, California's AB 2533 requires your city to help you get it permitted.
Our guide to legalizing an unpermitted garage conversion walks through the whole process, and we match homeowners with contractors who do exactly this work.
Reviews & Projects
Real Garage Conversions and Reviews
California homeowners come to GreatBuildz unsure how to find a contractor they can trust with a conversion, and leave with a finished unit they actually use. Here’s what a few of them had to say.
Used them to get a few estimates on converting a garage and existing space to an ADU. All 3 were reasonable quotes and we chose one to do the work that we felt very comfortable with… It’s hard to start with a contractor you don’t know but GreatBuildz knows them well and has worked with them so they only refer reliable contractors who are fully insured and licensed.
Dealing with contractors can be such a hassle, there are so many things you need to know and is easy to be fooled or scammed. GreatBuildz was a blessing, they guided me through the process on how to turn my garage into an ADU.
The project involved converting a bonus room into an ADU… This included a full kitchen, bath and laundry in a smaller space. The contractor that GreatBuildz referred was knowledgeable and capable. Their estimates were accurate, and they kept to the established project timeline.
Recent Garage Conversions
Garage Conversion FAQs
How much does a garage conversion cost in California?
How much does it cost to convert a garage into an office or gym?
How long does a garage conversion take?
Do I need a permit to convert my garage?
Can I legalize a garage that was already converted without permits?
Does a garage conversion count as an ADU?
Can my HOA stop a garage conversion?
What kind of contractor does garage conversions?
How much can a contractor ask for as a deposit in California?
Is GreatBuildz really free?
Finding a Garage Conversion Contractor in Los Angeles
Los Angeles might be the best garage conversion market in the country: hundreds of thousands of detached garages, ADU laws that make conversions straightforward, and rents that make the math work. The hard part isn’t the garage or the demand. It’s finding a contractor who handles the permit process cleanly and knows what they’re looking at when they open up a 70-year-old garage.
That’s why we started GreatBuildz. It’s a free service that matches homeowners with pre-screened general contractors who do this work every month. Every contractor passes our 10-point vetting process before we invite them into our network: license, insurance, background check, references, financial review, and more. Contractors can’t pay to join, and only the ones who meet our standards get in.
We match you with three vetted contractors to compare, plus a dedicated remodeling advisor to guide you from the first bid to final inspection. That matters here more than most places: many LA garages were built in the 1940s and 50s with minimal foundations and old electrical, and plenty were informally converted somewhere along the way. A contractor who converts garages every month checks slab condition, ceiling height, and utility runs before quoting, not after demo.
Using GreatBuildz costs you nothing, and we never sell your information. We match homeowners in Los Angeles and across California. If you’re still planning, our Los Angeles garage conversion guide covers costs in depth, and our guide to legalizing an unpermitted garage conversion covers the fix-it path. Thinking bigger than the garage? We also match homeowners with ADU contractors for new backyard units.
Hi, I’m Stephanie. I’ll match you with the right contractors for your project.