A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateFast, Reliable Garage Conversion Contractor Across San Jose
A garage conversion in San Jose typically costs $85,000 to $145,000 for a full living-space build-out with kitchenette and bath, and most projects take 10 to 16 weeks from permit to final inspection. That’s the honest range before we open a single wall. What changes that number is what’s behind the drywall: outdated wiring, a 60-amp panel, a shallow sewer lateral, or framing that doesn’t meet current seismic code. Our Garage Conversion Contractor team has opened enough San Jose garages to know exactly what inspectors will flag and what it costs to fix it before you sign anything. Call us at (669) 266-4319 if you want the real numbers for your specific garage.
We serve all of San Jose from our Bay Area dispatch office, with crews working locally in your neighborhood, not driving in from two counties away. Russ Delmar leads our San Jose team and he’ll be the one walking your garage with you at the estimate.
Why Lodgewick ADU San Jose Is San Jose’s Preferred Garage Conversion Contractor Company
We’ve been converting San Jose garages under the Kingswell Guarantee since 2010, and in a city where homeowners have heard every contractor promise and seen too many ghost, we’ve built our name on one thing: a written price before work starts. That means the number we quote you at the estimate is the number you pay, unless you approve a written change order. No door-knock surprises, no “we found something” mid-project.
Our San Jose customers call us back for second projects because our background-checked, uniformed crew shows up inside the arrival window we gave them, and they leave the job site cleaner than they found it. That’s the Kingswell Way, and it’s written into every contract. We answer our phones with a live person 24 hours a day, so when you have a question about your conversion at 9pm, you talk to a human, not a voicemail.
We also know San Jose’s building department and its pre-approved ADU plan library well enough to tell you upfront whether your garage will sail through plan check or get hung up on a seismic shear requirement. That local knowledge saves you weeks and thousands.
Garage Conversion to Living Space in San Jose
Garage Conversion to Living Space in San Jose means taking your existing attached or detached garage and turning it into a permitted, insulated, finished room that can serve as a family room, home office, gym, or guest suite. In San Jose, where single-family homes on 6,000-square-foot lots are the norm, the garage is often the largest underused square footage you own, and converting it costs far less per square foot than hiring a San Jose Home Addition Contractor to build from scratch.
Most San Jose garage-to-living-space conversions run $85,000 to $125,000 when they include drywall, insulation, flooring, electrical upgrade, lighting, and a mini-split or ducted HVAC tie-in. Adding a bathroom pushes the range to $110,000 to $145,000 because of plumbing, sewer tie-in, and San Jose’s inspection requirements for new fixtures in formerly unconditioned space.
Attached Garage Conversions
Converting an attached garage in a San Jose ranch home usually means tying into the existing roofline and foundation, which saves on structural work but often triggers upgrades to the main panel and shared walls. In neighborhoods like Cambrian and Berryessa, we regularly find original 100-amp panels that are already at capacity, so the conversion means a 200-amp service upgrade before the new circuits can go in. We write that allowance into your contract upfront.
Detached Garage Conversions
A detached garage conversion in San Jose gives you more design freedom but costs more per square foot because you’re running new utilities, new trenching for sewer and water, and meeting separate structure requirements for shear and anchoring. In Almaden Valley and Evergreen, where lots are larger and detached garages sit further from the house, we see trenching runs of 40 to 80 feet that add $8,000 to $15,000 to the project total. We quote that line item plainly.
Garage to Bedroom Conversion in San Jose
Garage to Bedroom Conversion in San Jose is the most requested scope we handle, especially in neighborhoods like Willow Glen, Rose Garden, and Naglee Park where growing families need another bedroom but don’t want to leave their street. Converting a garage to a bedroom means meeting California Building Code for egress windows, ceiling height, insulation values, and a closet, plus dedicated heating and cooling, and in San Jose, that almost always means a new subpanel or full electrical upgrade.
A garage-to-bedroom conversion in San Jose runs $75,000 to $115,000 for a code-compliant single bedroom without a bath, and $95,000 to $135,000 if you’re adding an en-suite bathroom. In pre-1980 garages, factor in the electrical and shear upgrades described below, or you’ll be surprised at first inspection.
The Egress and Light Requirement
San Jose requires any sleeping room to have an emergency escape window or door that opens directly outside, plus minimum natural light and ventilation. Most garages have the big roll-up door, which doesn’t count. We typically install a new 5-foot-wide egress window or a French door, and we include the header engineering in your written quote so it’s not an add-on later.
Insulation and Soundproofing
Garages weren’t built to be lived in. The slab typically has no vapor barrier, the walls have no insulation, and the ceiling joists are undersized for drywall. In San Jose’s older core, we almost always install a vapor barrier overlay or raise the finished floor, add R-21 wall and R-38 ceiling insulation, and re-frame ceiling joists to carry the load, plus a layer of quiet-rock or sound batt if the bedroom shares a wall with the main house.
Trusted Brands We Service in San Jose
We work with prefab ADU manufacturers and material brands that suit San Jose lots and budgets, including Abodu for turnkey detached units, Cover for panelized builds, and our San Jose Dvele service for precision-built prefab units, plus James Hardie siding for fire-rated, low-maintenance exteriors that hold up through San Jose’s wet winters and dry summers. Because our San Jose crews stock common components locally, we’re not waiting on a truck from out of state when a change order needs a specific panel or piece of flashing. If you’re weighing a prefab unit against a conventional conversion, we can price both honestly and tell you which fits your lot, your timeline, and your inspection reality.
Common Garage Conversion Contractor Problems We See in San Jose Homes
San Jose’s housing stock is older than most of the surrounding cities. The garages we open here date back to the 1950s, 60s, and early 70s, and they hide the same issues over and over. Here’s what we find most often, and how it hits your budget:
- Original 60-amp electrical panels and knob-and-tube wiring: Opening garage walls in San Jose routinely exposes original 60-amp service and old knob-and-tube circuits feeding garage outlets and lights. Adding a bedroom or living space then triggers a code-required panel upgrade to 100 or 200 amps, which can add $6,000 to $12,000 before you account for the rewire itself.
- Insufficient foundation anchors and shear walls: San Jose sits in a high-seismic zone, and the California Building Code now requires hold-down anchors and shear panels that 1950s-70s slabs were never built with. If we don’t retrofit the garage’s shear wall, the conversion fails inspection, and you get a stop-work order.
- Shallow clay sewer laterals under 1950s garages: Original San Jose sewer laterals were laid shallow, often only 12 to 18 inches below the slab, which won’t maintain fall for a new bathroom tied into the main line. Adding a bath often means trenching through the garage slab and upsizing the lateral to meet current code, a $10,000 to $20,000 line item that almost never shows up in a competitor’s flat quote.
- Slab moisture and lack of vapor barrier: 1950s and 60s garage slabs in San Jose were poured without a vapor barrier, and in wet winters, ground moisture wicks up through the concrete. Any finished floor over that slab needs a membrane or you’ll be replacing warped flooring in two years.
Pricing for Garage Conversion Contractor in San Jose, CA
Here are real San Jose numbers, the same ranges we give on the phone and at the kitchen table. A straight garage-to-living-space conversion without a bathroom runs $85,000 to $125,000. A garage-to-bedroom conversion runs $75,000 to $115,000 for the bedroom alone. Adding a bathroom to either scope runs $95,000 to $145,000 depending on sewer depth, trenching distance, and whether you need a panel upgrade. Detached conversions run 10 to 15 percent higher than attached because of new utility runs and separate structural requirements. Any quote that’s dramatically lower than this is almost certainly excluding the seismic retrofits and electrical upgrades San Jose inspectors will require the moment we open your walls. We write every one of those allowances into your contract before you sign. Call (669) 266-4319 for a fixed written estimate on your garage.
We Also Serve Cities Near San Jose
Our San Jose crews serve Milpitas, Santa Clara, Los Gatos, and Los Altos as well, and we know the different municipal plan check requirements in each. If you’re in one of those cities, our Garage Conversion Contractor team can tell you upfront whether your garage conversion triggers the same seismic and electrical upgrades we see in San Jose or a lighter review. Call us and we’ll walk through it.
Serving San Jose, CA - Our Local Coverage Area
We’re based in the San Jose area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About Garage Conversion Contractor in San Jose
San Jose’s pre-approved ADU plan library can shorten plan check to a few weeks for new detached units, but it does not bypass the garage conversion permit when you’re opening existing walls, which means your 1950s-70s garage still gets inspected for electrical, seismic shear, and sewer compliance. Our team coordinates both paths so you don’t lose time waiting on a revision cycle. Call (669) 266-4319 and we’ll tell you honestly which permit route your project falls under.
We stop work, photograph the issue, and write you a change order with the exact cost to bring the wiring to current San Jose code, which you approve in writing before we touch another wire. No surprise invoice. Call us at (669) 266-4319 if you want to know what a rewire on a 1960s Willow Glen garage typically costs.
Because most contractors price a conversion without opening the drywall, and in San Jose’s pre-1980 garages, that first inspection routinely uncovers a 60-amp panel, missing shear anchors, or a shallow sewer lateral that code requires to be upgraded. We price those allowances upfront so your quote doesn’t jump. Call (669) 266-4319 for a written estimate that already accounts for what we know we’ll find.
We locate the lateral, measure its depth and fall, and if it’s too shallow to meet San Jose code, we write the trenching and upsizing into your contract as a line item before we pour anything. In many 1950s garages this means saw-cutting the slab and digging down 3 to 4 feet. Call (669) 266-4319 and we’ll tell you what a lateral replacement on your street is likely to cost.
Yes. San Jose’s high-seismic requirements apply to any converted space, not just additions, so any pre-1980 garage we open gets evaluated for shear wall and hold-down retrofits, and most need at least some. We include that engineering in our written price so it’s not a change order later. Call (669) 266-4319 to schedule a free estimate and we’ll check yours in person.
Get Your San Jose Garage Conversion Priced in Writing
We’re Russ Delmar and the crew at Lodgewick ADU San Jose, and we’ve been opening San Jose garages long enough to know what’s behind the drywall before we quote you. Call (669) 266-4319 to schedule a free on-site estimate. We’ll walk the garage with you, point out what the inspector will flag, and hand you a written price that covers the whole job, including the electrical, seismic, and sewer upgrades that almost every pre-1980 garage in San Jose needs. No pressure and no surprises. Just the real numbers, in writing, before you decide.
Written by Russ Delmar, Owner at Lodgewick ADU San Jose, serving San Jose and the surrounding Bay Area since 2010.
