A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Millbrae, CA
Lodgewick ADU Builders is the ADU company Millbrae homeowners call when they want a straight answer about adding livable space to their property. An accessory dwelling unit, or ADU, is a second, smaller home built on the same lot as your main house, and in Millbrae that usually means a garage conversion, a basement carve-out, or a tuck-under unit on a hillside lot. The houses here are mid-century, the lots are tight, and the fog rolls in most evenings, so every project needs a builder who plans for drainage, slope, and below-grade moisture from day one. Call (707) 760-0502 for a free estimate and we’ll put a written price in front of you before anything starts.
Why Millbrae Homes Are Different
Millbrae sits right on the BART/Caltrain line, which has pushed land values up and made ADUs one of the smartest ways to add square footage without buying a bigger house. The catch is the terrain. Many Millbrae homes climb the hills east of El Camino Real, where lots slope enough that a standard flat-pad ADU won’t work without retaining walls and careful drainage. We’ve walked hillside properties where the best answer is a tuck-under unit, the kind where the garage space below the main floor becomes a one-bedroom apartment, and the retaining wall doubles as a privacy screen for the front door.
The housing stock itself is another factor. Millbrae is full of mid-century single-family homes, many with oversized garages built for a single car and a workbench, and basements that were never finished. Those spaces are often the easiest path to an ADU, but the foundations underneath them are 60 to 70 years old in a lot of cases. Seismic anchoring, shear walls, and sill-plate reinforcement are common line items on Millbrae garage conversion and basement ADU jobs, and we factor them into the written price up front rather than discovering them halfway through. The coastal fog also means below-grade units need real ventilation, vapor barriers, and dehumidification, not just a coat of paint and some drywall. A basement ADU in Millbrae that skips moisture management will smell like a wet garage within a year, and that’s a call-back we don’t want to make, so we don’t create it.
Our Main Millbrae Services
Most Millbrae homeowners reach out to us for one of three projects, and each one has its own dedicated page with pricing, timelines, and the local permit realities spelled out.
Home Addition Contractor in Millbrae
A home addition in Millbrae is different from one in a flat East Bay suburb because of the slope. A ground-level bump-out on a hillside lot often needs stepped footings, short retaining walls, and roof tie-ins that respect the existing mid-century lines. We handle the structural engineering, the city submittal, and the build as one scope, so homeowners aren’t juggling three separate contractors. A written price comes before any work starts, and the 365-Day Done Right Promise applies to every addition we build. Home Addition Contractor in Millbrae
Garage Conversion Contractor in Millbrae
Garage conversions are the most common ADU path in Millbrae, because the mid-century garages here are already oversized and the lot is already paid for. The work typically involves foundation upgrades, new electrical from the panel, insulation and drywall, and a bathroom, and on hillside lots we often see tuck-under layouts where the garage is below the living floor and needs water management designed in from the start. The written price covers everything we can see, and we name the things we’ll check before we open walls. Garage Conversion Contractor in Millbrae
ADU Builders in Millbrae
As ADU builders, we guide Millbrae homeowners through the whole process: site assessment, permit-ready plans, foundation and utility work, the build itself, and the final inspection. For lots that can’t support a stick-built unit given the slope or the access, we work with prefab ADU makers like Abodu and Cover, and we’ve also used Tuff Shed as a shell for detached work studios that later become permitted ADUs. Every project gets a written price and a written guarantee before work begins. ADU Builders in Millbrae
What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Brands We Service in Millbrae
We work with Abodu, Cover, and Tuff Shed on Millbrae projects, and we use James Hardie siding and trim on the exterior of many of our builds and conversions. Our crews are hands-on with these systems, so if you have a prefab ADU from one of these makers and it needs foundation work, utility tie-in, or finishing, call us and we’ll quote the work in writing. See our brands for more detail.
Pricing for ADU Company in Millbrae, CA
| Service | Typical range in Millbrae |
|---|---|
| Garage conversion to ADU (full build) | $120,000 – $220,000 |
| Garage conversion (finish-out only) | $45,000 – $90,000 |
| Detached ADU, stick-built | $200,000 – $380,000 |
| Prefab ADU (Abodu or Cover, installed) | $180,000 – $330,000 |
| Tuff Shed shell as work studio (unpermitted) | $8,000 – $25,000 |
| Basement ADU build-out | $140,000 – $260,000 |
| Home addition, ground-level bump-out | $150,000 – $350,000 |
| Foundation and seismic retrofit on existing garage | $15,000 – $40,000 |
| Retaining wall for hillside ADU site | $12,000 – $45,000 |
| Utility tie-in (water, sewer, electrical) | $8,000 – $25,000 |
| Permit and plan set (architectural + structural) | $8,000 – $20,000 |
The two things that push Millbrae pricing up are slope and foundation age. A hillside lot with poor access can add several thousand in retaining and excavation work, and a 1960s garage that needs a full seismic retrofit will always cost more than one on a flat slab that’s already sound. Whatever the number is, it’s in writing before any work starts, and that written price does not change at the door.
Neighborhoods We Serve in Millbrae
We work across Millbrae, from the flats near Broadway up into the hills east of El Camino Real. Each pocket has its own typical lot shape and access pattern, and we plan for that when we walk the property.
- Mills Estates
- Green Hills
- Lomita Park
- Meadow Glen
- Central Millbrae (near BART and El Camino)
Scheduling in Millbrae is generally straightforward since crews stage from the San Francisco Bay Area office, and a typical estimate visit happens within a few business days of your call.
Service Area – Cities Near Millbrae
Beyond Millbrae, our crews cover the surrounding peninsula and northern San Mateo County communities. If you’re a few minutes north or south, you’ll find the same written-price policy and the same 365-Day Done Right Promise. We work in San Bruno, CA, Daly City, CA, San Carlos, CA, and San Francisco, CA.
Serving Millbrae, CA - Our Local Coverage Area
We’re based in the Millbrae 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 ADU Company in Millbrae
Yes. Millbrae has its own building department review process, and we handle the plan submittal, structural engineering, and permit tracking as part of the job. Hillside lots often trigger additional geotechnical review, and we include that in the written price when we know it’s required.
A garage conversion usually runs four to seven months from permit submittal to final inspection. A detached ADU or a home addition can run seven to twelve months, depending on slope, foundation work, and city review time. We put the schedule in writing and name the window before work begins.
No. The written price we give you before the job starts is the price we build to. If we open a wall and find something unexpected, like rotted sill plates or old knob-and-tube wiring, we’ll show you, explain what it means, and put any change in writing for your sign-off before we proceed. Call (707) 760-0502 for an exact quote, free of charge.
What happens when you call
- 1A real person answersNo phone trees - talk to a local adu pro.
- 2You get an upfront price rangeHonest numbers before anyone is dispatched. No surprises.
- 3We come out and measureLicensed & insured, at a time that suits you - the visit and the quote are both free.
- 4You get the price in writingLine-itemed, yours to keep, and nothing starts until you say go.
What Millbrae Customers Say
"The ADU came out beautiful and the permitting, which terrified me, was handled start to finish. They kept me updated every week so I was never wondering what was happening."
- Shauna Mills"Turned our detached garage into a little guest house. Clean crew, respectful of the neighbors, and no mystery charges at the end. Love how it turned out."
- Carmela Fontes"I was nervous about adding on but they walked me through every step and every cost before we started. No surprise change orders halfway through like I'd heard horror stories about."
- Eleanor Pratt
