Garage Conversions

We serve Northern California across three regions: the San Francisco Bay Area (six counties from Alameda to Santa Clara), Greater Sacramento (Sacramento out to Roseville, Folsom, and Davis), and the Central Valley (Stockton to Modesto). Our crews are based in Castro Valley. We handle permits and know the building codes for each jurisdiction, which matters because requirements and fees vary significantly between cities.

We offer $0-down financing with approved credit, 12-month same-as-cash plans, and extended terms up to 15 years for larger projects. You only pay for completed, inspected work — we never ask for full payment before the job is done. Your project manager will walk you through every option during your estimate appointment. We also accept checks, ACH, and all major credit cards.

Yes. CSLB License #1078806 — verify it anytime at cslb.ca.gov. We carry $2M general liability, full workers’ comp, and are bonded per California law. We hold GAF Master Elite, Owens Corning Preferred, CertainTeed ShingleMaster, and James Hardie Elite Preferred certifications — each requires annual training and quality audits to maintain. We’re happy to provide proof of insurance before any work begins.

Most exterior projects in Northern California require a building permit. Fees vary by city — Oakland runs $200–$600, Peninsula cities often more. We handle the entire permit process: application, plan submission, and scheduling inspections. Permit fees appear as a separate line item in your estimate so you’ll see every cost upfront. For homes in WUI fire zones (Berkeley Hills, Oakland Hills, parts of Marin), we ensure full compliance with local fire-rated material requirements.

Garage conversions in the Bay Area cost $80,000–$150,000 depending on size, finishes, and structural work required. A single-car garage (200–250 sq ft) with standard finishes starts around $80K. A two-car garage (400–500 sq ft) with full kitchen, bathroom, and quality finishes runs $120K–$150K. These figures include permits, design, engineering, and construction.

Total timeline is 4–6 months: 2–3 weeks for design and engineering, 4–8 weeks for permitting (covered by our 60-day permit guarantee), and 6–10 weeks of construction. Garage conversions are the fastest ADU type because the existing structure eliminates foundation and framing phases.

No. California law (AB 68, effective 2020) prohibits cities from requiring replacement off-street parking when a garage is converted to an ADU. This applies statewide regardless of your local zoning. Most homeowners use their driveway or street parking instead.

Both attached and detached garages can be converted. Attached garages often cost less because plumbing and electrical are closer to existing connections. The main additional requirement for attached garages is fire separation: 5/8" Type X fire-rated drywall on the shared wall and a 20-minute fire-rated door if maintaining an interior connection.

We frame the opening with standard stud walls, add insulation, and finish the exterior with siding, windows, and an entry door that match your home's existing materials and style. Done well, the conversion looks intentional rather than like a modified garage.

Almost always. Most garages run on a 15–20 amp circuit, which can't support a dwelling unit's electrical load (kitchen appliances, HVAC, water heater, outlets). We typically upgrade the main house panel from 100A to 200A and install a new 60–80 amp subpanel for the ADU. Panel upgrade cost is included in our project pricing.

At minimum, a bathroom requires hot and cold supply lines and drain/waste/vent connections. If adding a kitchen, you'll need additional supply lines, a drain line, and possibly a gas line. Attached garages near existing plumbing keep costs lower. Detached garages may need a new sewer lateral run of 20–60 feet, which adds $5,000–$12,000.

For attached garages, California Building Code requires a one-hour fire-rated assembly on the wall shared with the main house (5/8" Type X drywall on both sides) and a solid-core, self-closing, 20-minute fire-rated door if an interior connection exists. Detached garages with 3+ feet of separation from the main house have no special fire separation requirements.

A bathroom is required by code for any ADU, so every garage conversion includes one. A full bathroom (shower, toilet, vanity) typically adds $15,000–$25,000 to the project depending on distance from existing plumbing lines and finish selections.

Permitting timelines vary by city: Palo Alto and Fremont process in 4–6 weeks, San Jose and Oakland in 6–8 weeks, San Francisco in 8–12 weeks. Our 60-day permit guarantee means we manage all plan check corrections and resubmissions. If permitting exceeds 60 days due to our documentation, we cover resubmission costs.

Yes. A stackable washer/dryer closet fits in most garage conversions and is a strong selling point for rental units. It requires a 240V electrical circuit, hot and cold water supply, a drain connection, and a dryer vent to the exterior. We include a laundry closet option in all two-car garage conversion designs.

Garage conversions must meet California Title 24 energy standards. This means R-13 minimum in walls (we use R-15 or R-21 depending on framing depth), R-30 in the ceiling, and insulation under the slab or a floating insulated subfloor system. The garage door wall, once framed in, gets the same insulation as all other walls.

Common options include HELOC (home equity line of credit), home equity loan, cash-out refinance, and the CalHFA ADU Grant Program (up to $40,000 for qualifying homeowners). With Bay Area home values, most homeowners have ample equity. Monthly payments on a $120K HELOC at current rates are roughly $800–$1,000, which is often covered by rental income.

Bay Area garage conversion ADUs rent for $1,500–$2,800 per month depending on location, size, and finishes. A studio in Oakland or San Jose rents for $1,500–$2,000; a one-bedroom in Palo Alto or San Mateo commands $2,200–$2,800. At these rates, most garage conversions pay for themselves in 5–8 years.

California requires 7’6" minimum finished ceiling height for habitable rooms. Most two-car garages built after 1960 meet this standard. Single-car garages and pre-1960 structures sometimes fall short. If your garage is close but under the minimum, raising the roof plate is possible but adds $10,000–$20,000 to the project. We measure during our free assessment.

Yes, modestly. Converting a garage to permitted living space triggers reassessment of the improvement value only (not the land) under Proposition 13. Typical property tax increases run $1,000–$2,500 per year, which is offset many times over by rental income potential of $1,500–$2,800 per month.