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 Martinez
Garage conversion in Martinez typically costs between $95,000 and $160,000 for a full ADU with kitchen and bath, and most projects run 10 to 16 weeks from permit submission to final inspection. That’s the straight answer we give homeowners on Estudillo Street, up near Hidden Lakes, and everywhere in between. We’re the Garage Conversion Contractor team from Lodgewick ADU San Francisco, and we’ve done enough work in Martinez to know exactly what your pre-1960s detached garage is hiding under that slab. Call (707) 760-0502 and you’ll get a live person, not a voicemail tree.
Why Lodgewick ADU San Francisco Is Martinez’s Preferred Garage Conversion Contractor Company
Russ Delmar leads our Martinez garage conversion work, and he’s spent enough hours under hillside foundations here to know what the city inspector will flag before the inspector even arrives. Martinez homeowners call us because we write the price down before we touch a single nail, and that number doesn’t change at the door. The 365-Day Done Right Promise backs every conversion we complete in Martinez: if something isn’t right within a year, we come back and fix it, free. That’s in writing on every project.
Our clients in Martinez tell us the same thing: they’d been burned before by a contractor who reused an old slab without checking the rebar, or who never showed up during the rough-in. We show up in the window we give, our crew wears uniforms and passes background checks, and the job site gets cleaned every single day. Serving Martinez means understanding that your 1940s garage isn’t the same as a 1990s garage in a newer East Bay suburb.
Garage Conversion ADU in Martinez
A Garage Conversion ADU in Martinez is a permitted dwelling unit built inside your existing garage footprint, with its own kitchen, bath, entrance, and address, and it’s the fastest way to add rentable or family space on a lot that already has the structure standing. In Martinez, where much of the housing stock dates from the early-to-mid 20th century and lots are generous, a garage conversion ADU typically runs $95,000 to $160,000 depending on whether you’re converting an attached single-car or a detached two-car with separate electrical service.
Older Slab, New Loads
Many pre-1960s garages in downtown Martinez sit on slabs poured without rebar and with footings only 12 inches deep. That’s not a detail, it’s the central issue. We verify slab thickness and footing depth before we ever give you a written price.
110 mph Wind Uplift
California’s Title 24 standard for Martinez requires your converted garage to resist 110 mph ultimate design wind speed for Risk Category II structures. The roof-to-foundation connection has to be continuous. We install Simpson Strong-Tie HDU hold-downs and shear panels as standard on every Martinez ADU conversion.
Garage Apartment Conversion in Martinez
A Garage Apartment Conversion in Martinez is a garage turned into a separate rental unit or in-law apartment, often without the full ADU permit path if the space stays under 500 square feet, and it’s a smart move for homeowners near downtown Martinez who want rental income without building new. A garage apartment conversion here runs $80,000 to $135,000 for a studio or one-bedroom, with the final number driven by how much structural retrofit your existing garage needs to meet wind-load standards.
Rental-Ready Compliance
Martinez requires the same wind-load path hardware for a garage apartment as it does for a full ADU, even if the square footage is smaller. That means hold-downs, straps, and either new shear panels or engineered moment frames on the garage door wall. We price that in from the first line item.
Insurance Paperwork That Pays
When the work is permitted and the wind-load documentation is filed, homeowners report insurance premium credits of 10 to 15 percent on the ADU portion of their policy. We hand over the structural engineering letters and inspection sign-offs at closeout, not months later when you’re trying to renew.
Trusted Brands We Service in Martinez
Our Martinez garage conversion projects go faster because we work directly with the material suppliers that carry what this city actually approves. We regularly specify James Hardie fiber-cement siding over new plywood shear panels, which passes Martinez’s wind-load inspection without a second look. For prefab ADU options on spacious hillside lots, we work with Plant Prefab and Tuff Shed, both of which carry engineered wind-resistance documentation that satisfies Contra Costa County plan check. We don’t make you wait on parts shipped from out of state. We know what the Martinez inspector accepts, and we stock the hardware locally.
Common Garage Conversion Contractor Problems We See in Martinez Homes
- Undersized footings on pre-1960 garages. Many downtown Martinez garages were built on 12-inch footings with no rebar. To hit the 110 mph wind-load standard, we saw-cut the perimeter, pour new 18-inch footings, and epoxy-dowel rebar into the existing slab.
- Missing continuous load-path hardware. Crews that cut corners skip the hold-downs and straps connecting the garage roof to the foundation. On hillside lots like those near Hidden Lakes, wind uplift pulls the structure apart at exactly those connection points.
- Slab reuse without verification. A contractor reuses the old slab because it “looks fine.” It isn’t. We core-sample the slab before we bid, and if there’s no rebar, that’s a line item in your written price, not a surprise change order later.
- No structural engineering in the quote. Some Martinez quotes leave out the $3,000 to $5,000 for structural engineering and plan-check fees. Then the homeowner finds out mid-project that the permit can’t be issued without a wind-load stamp. We include engineering in every quote from day one.
Pricing for Garage Conversion Contractor in Martinez, CA
Here’s what a Martinez garage conversion actually costs. A basic garage-to-living-space conversion with no kitchen and a bathroom added runs $80,000 to $110,000. A full garage conversion ADU with a kitchen and separate entrance lands between $95,000 and $160,000, with the spread driven by footing depth, wind-load retrofit scope, and whether you’re on flat downtown grid or a hillside lot near Hidden Lakes. Structural engineering and plan-check fees for wind compliance run $3,000 to $5,000 and are always itemized in our written price. We never hand you a number that grows once the work starts. Call (707) 760-0502 for a free written estimate on your Martinez garage conversion.
We Also Serve Cities Near Martinez
Our crews cover Martinez and the surrounding Contra Costa communities, including Orinda, Moraga, Richmond, and Emeryville. If your home sits in one of these nearby cities, the same written-price commitment and 365-Day Done Right Promise apply. Call (707) 760-0502 to schedule a free estimate at your property.
Serving Martinez, CA - Our Local Coverage Area
We’re based in the Martinez 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 Martinez
Your Martinez garage conversion must meet California Title 24 requirements for an ultimate design wind speed of 110 mph for Risk Category II structures. That means the roof-to-foundation load path is continuous, with Simpson Strong-Tie HDU hold-downs, straps, and shear panels installed and inspected. Our written quotes always include the engineering for this standard, so there’s no gap between what the plan says and what the inspector approves. Call (707) 760-0502 for a free estimate that covers wind-load compliance from the first line item.
Yes. Many pre-1960 garages in Martinez have footings only 12 inches deep and slabs poured without rebar, so they need footing enlargement and epoxy-doweled rebar connections before they can resist 110 mph wind uplift. We saw-cut the perimeter and pour new 18-inch footings as part of the conversion. This work is always in our written price before we start, never added later. Call (707) 760-0502 and we’ll walk your specific garage with you.
James Hardie fiber-cement siding over new plywood shear panels is the most common approved assembly we use in Martinez, and it passes local plan check without pushback. Some homeowners on hillside lots also use engineered prefab panels from Plant Prefab or Tuff Shed, which carry wind-load documentation that satisfies Contra Costa County. We match the product to your lot exposure and budget. Call (707) 760-0502 for a product recommendation specific to your street.
When wind-load compliance is documented through permitted plans and inspection sign-offs, Martinez homeowners often see a 10 to 15 percent credit on the ADU portion of their homeowners insurance. That documentation comes from structural engineering letters and the final building inspection record, which we hand over at closeout. If the work isn’t permitted, the ADU can be excluded from coverage entirely. Call (707) 760-0502 and we’ll explain what your project needs to generate that paperwork.
Your Martinez garage conversion needs a structural engineering stamp on the wind-load design before the building permit is issued, and the inspector will check hold-downs, straps, and shear panels during the rough-in and final inspections. Plan-check fees for wind resistance run $3,000 to $5,000 and are itemized in our written price. We pull the permits, we schedule the inspections, and we keep every sign-off on file for your insurance. Call (707) 760-0502 for a free written estimate that covers the entire permit path.
If you have a garage in Martinez that’s been sitting half-used for years, we’ll give you a real number in writing and a schedule we’ll actually keep. Call (707) 760-0502 to schedule your free estimate.
Written by Russ Delmar, Owner at Lodgewick ADU San Francisco, serving Martinez through the Kingswell Guarantee since 2010.
