







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Los Altos, CA
Los Altos is one of the toughest places in the Bay Area to build an accessory dwelling unit, garage conversion, or home addition, and one of the most rewarding. The lots are large, the planning department is rigorous, and the value added to a property here is substantial. A Lodgewick ADU Builders project in Los Altos means working around heritage oaks, navigating strict design review, and building to seismic standards that many contractors never touch. If you’re planning an ADU, garage conversion, or addition in Los Altos, call us at (669) 266-4319 for a written estimate before any work begins.
Why Los Altos Homes Are Different

Most Los Altos homes sit on lots of 10,000 square feet or more, which sounds generous until you start mapping where an ADU can legally go. Setbacks, heritage tree protection zones, and utility easements shrink the buildable area fast. Many of the homes are mid-century ranches that have been remodeled multiple times, which means we often find surprises behind the walls: outdated electrical panels, undersized gas lines, or foundation conditions that need addressing before framing starts.
The climate here is mild but the winter rains are real. Drainage and waterproofing matter on flat lots, and they matter even more on the hillside properties in the Los Altos Hills-adjacent zones where slope stability and retaining walls come into play. Los Altos sits in a seismically active region, so every ADU we build must meet current California seismic and Title 24 energy codes, including roof-mounted solar or another approved renewable energy source. These are not optional upgrades. They are the cost of building legally in Los Altos, and we price them into the written quote up front so there are no surprises later.
What we see consistently in Los Altos: homeowners are not building rental units as an afterthought. They are building housing for aging parents, adult children, or long-term tenants who work in tech and expect the same finish level as the main house. EV charger rough-ins, mini-split HVAC, custom cabinetry, and two-story ADUs to preserve yard space are all common requests here.
Our Main Los Altos Services
Los Altos homeowners call us most often about three types of projects: adding square footage to the main house, converting an existing garage into living space, and building a detached or attached ADU from the ground up. Each of these has its own Los Altos page with detailed pricing and local specifics.
Home Addition Contractor in Los Altos
A home addition in Los Altos usually means expanding a mid-century ranch outward or upward. The existing structure often needs structural upgrades before the new square footage can tie in, especially on older homes that predate current seismic codes. We handle the architectural coordination, structural engineering, permits, and construction as a single scope of work with one written price. On a typical Los Altos addition, mature landscaping and heritage trees often dictate the site plan, so we work with the city’s arborist requirements from day one rather than discovering them mid-project. Home Addition Contractor in Los Altos has the full pricing breakdown and local permit detail.

Garage Conversion Contractor in Los Altos
Converting an attached garage into a junior ADU or full ADU is often the fastest path to livable space on a Los Altos lot, but it is rarely as simple as drywall and flooring. Many Los Altos garages were built with slab foundations that need leveling, electrical services that cannot support a full dwelling unit, and no insulation to speak of. We have converted garages on lots throughout Los Altos, and we know what the city’s inspectors will flag before they flag it. The written quote includes all required seismic, insulation, and Title 24 upgrades before work starts. Garage Conversion Contractor in Los Altos covers costs, timelines, and the conversion process for Los Altos specifically.

ADU Builders in Los Altos
Detached ADUs in Los Altos are frequently two-story structures built to preserve what remains of the yard. The city’s setback rules and lot coverage limits, combined with heritage tree protections, often push the footprint smaller and the footprint up. We also see growing demand for the city’s ADU amnesty program, where owners of unpermitted units need to bring them into compliance. Our team handles the retrofit drawings, engineering, and corrections required by the city, along with new ground-up builds using prefab manufacturers like Abodu and Plant Prefab where the lot and budget fit. ADU Builders in Los Altos has the complete guide to detached, attached, and garage-conversion ADU costs in the city.

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 Los Altos
We work with established ADU and building-material brands that hold up to Los Altos conditions and design review. Most Los Altos projects in our pipeline use James Hardie siding for its fire resistance and low maintenance, and we have built with prefab ADU systems from Abodu and Plant Prefab. Learn more about the equipment and materials we service and install at our brands. We stock common components locally so warranty work moves quickly.
Pricing for ADU Company in Los Altos, CA
| Service | Typical range in Los Altos |
|---|---|
| Detached ADU (new build) | $250,000 – $450,000 |
| Attached ADU | $180,000 – $350,000 |
| Garage conversion to ADU | $120,000 – $250,000 |
| Junior ADU (JADU) within existing home | $80,000 – $150,000 |
| Prefab ADU (installed, site work included) | $220,000 – $400,000 |
| Home addition (ground-floor, 300 – 600 sq ft) | $180,000 – $380,000 |
| Second-story addition | $300,000 – $600,000 |
| Kitchen addition | $120,000 – $250,000 |
| Primary suite addition | $150,000 – $300,000 |
| Permit and design fees (Los Altos) | $15,000 – $40,000 |
| Site prep, foundation, and drainage | $25,000 – $80,000 |
| Utility connections and solar compliance | $10,000 – $35,000 |
What pushes a Los Altos project toward the top of these ranges is usually the lot, not the structure: hillside grading, heritage tree protection, long utility runs from the street, and design review revisions all add cost. Every Lodgewick project gets a written price before work starts, and that price does not change at the door. The Kingswell Guarantee is a written commitment, not a verbal one.
Neighborhoods We Serve in Los Altos

We work throughout Los Altos, from the flat, established streets of North Los Altos to the larger lots and newer builds south of Foothill Expressway. No two neighborhoods have the same setback or tree-protection profile, and we price each job against the actual lot conditions, not a generic city average.
- North Los Altos
- South Los Altos
- The Country Club area
- Loyola Corners
- Woodland Acres
For most Los Altos projects, we can schedule an on-site walkthrough and measurement visit within a week of your call, and written estimates follow within days after that.
Service Area – Cities Near Los Altos
While this page covers Los Altos, our crews also work regularly in Palo Alto, CA, where similar mid-century housing stock and tight planning rules apply, as well as the larger hillside lots of Portola Valley, CA. To the south, we serve Santa Clara, CA for homeowners who want quicker-moving permits, and Los Gatos, CA for hillside ADUs and additions. Each city has its own permit timeline and lot profile, and we scope every job against the actual municipality.
Serving Los Altos, CA - Our Local Coverage Area
We’re based in the Los Altos 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 Los Altos

We can typically get an estimator to your Los Altos property within a week of your first call, and a written estimate follows within days of that site visit. Design, engineering, and the city’s design review process are the variables that determine when construction actually begins. Call (669) 266-4319 to get the process started with a free estimate.
State law limits what an HOA can restrict on ADU construction, but some Los Altos neighborhoods with active HOAs still impose design review conditions on exterior finishes, rooflines, and landscaping. We read the governing documents early in the process and flag any restrictions before they become change orders.
The design review process can add iterations, but your Lodgewick price is written after reviewing your specific project scope. If the city requires changes that affect the build, we put a revised written price in front of you before proceeding. There are no surprise change orders at the door. Call (669) 266-4319 for a free estimate on your Los Altos project.
If you’re planning an ADU, garage conversion, or home addition in Los Altos, start with a written price. Call (669) 266-4319 to schedule a free estimate with Lodgewick ADU Builders, led by Russ Delmar and operated under The Kingswell Guarantee. A live person answers, 24 hours a day.
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 Los Altos Customers Say
"Converted our garage into a rental studio. The crew was respectful of the neighbors and kept the site clean. It's bringing in rent now and paid for itself faster than I expected."
- Grace Yoon"Built a backyard unit for my mother in law. They handled the permits, gave me a real timeline, and stuck to it within a few days. The written price is what we paid, which anyone who's done construction knows is rare."
- Dennis Fairchild"Added a suite for my dad. They walked us through every cost before a hammer swung and stuck to it. The written price is what we paid, no change orders."
- Ingrid Salazar





