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 Hills, CA
Planning an ADU in Los Altos Hills means working with a lot that is typically an acre or larger, often on a slope, and almost always subject to design review that cares about how the building meets the land. Lodgewick ADU Builders, led by Russ Delmar, plans accessory dwelling units, garage conversions, and home additions around those realities: grading, drainage, septic or sewer capacity, and fire-resistant exterior choices. If you’re weighing whether your Los Altos Hills property can support an ADU, call (669) 266-4319. We’ll walk the site with you and give you a written price before any work starts.
Why Los Altos Hills Homes Are Different
Los Altos Hills enforces a one-acre minimum lot size, which keeps the town semi-rural and low-density. That shapes ADU planning more than most homeowners expect. A detached ADU on a hillside parcel often needs engineered retaining walls, a geotechnical report, and stormwater controls that a flat suburban lot would never trigger. Properties on the western ridges and along roads like Elena Road or La Paloma Road also sit in higher wind exposure zones, which means siding, roof attachment, and window flashing all get specified differently.
Many homes here were custom-built from the 1950s onward, and a large share are served by private septic systems or long sewer laterals rather than a short city connection. Adding an ADU frequently means proving the existing septic field can handle the extra bedroom, or paying for a sewer extension that can add five figures to the job before a foundation is even poured. The Mediterranean climate, dry summers and wet winters, also pushes drainage and erosion control to the front of every plan. We account for all of that in the written quote, so the number we give you is the number you build against.
Our Main Los Altos Hills Services
Most Los Altos Hills homeowners come to us with one of three goals: more living space attached to the main house, a garage turned into a rentable or family unit, or a new detached ADU on the back of a large lot. Each has its own Los Altos Hills page with local pricing and specifics.
Home Addition Contractor in Los Altos Hills
A home addition in Los Altos Hills often means extending into a hillside or cantilevering over a slope, not just bumping out a wall on a flat lot. Setbacks on one-acre parcels are generous but viewshed and ridgeline rules can constrain exactly where square footage can go. We handle the structural engineering, foundation work, and the design-review submittal so the addition fits both the house and the hillside. For a full breakdown of what that looks like on your street, see our Home Addition Contractor in Los Altos Hills page.
Garage Conversion Contractor in Los Altos Hills
Garage conversions are the fastest path to livable square footage in Los Altos Hills, because the foundation and roof already exist. Many older hillside garages, though, were built as detached structures with minimal insulation and no sewer stub, so the real work is often underground: tying into the septic system or sewer lateral, and bringing power up to code for a dwelling unit. We inspect the existing slab and framing before we price anything. Read the local specifics on our Garage Conversion Contractor in Los Altos Hills page.
ADU Builders in Los Altos Hills
A detached ADU on a Los Altos Hills lot is usually a 600 to 1,200 square foot unit sited to preserve the main home’s view while staying within ridgeline and setback rules. Septic capacity is the most common feasibility question we answer first, because it can decide whether a two-bedroom unit or a one-bedroom unit makes sense on your parcel. We plan around the existing septic field, the slope, and the design-review board’s expectations for materials and rooflines. For pricing and process, visit our ADU Builders in Los Altos Hills page.
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 Hills
We work with several established ADU and materials brands, including our brands like Plant Prefab, Tuff Shed, and James Hardie. On Los Altos Hills jobs, James Hardie siding shows up often because of the fire-resistant spec in wooded areas, and Plant Prefab panels can shorten the foundation-to-dry time on a hillside build by weeks. Parts and material lead times are confirmed before the quote is final, so the schedule we write is the schedule we keep.
Pricing for ADU Company in Los Altos Hills, CA
| Service | Typical range in Los Altos Hills |
|---|---|
| Feasibility site visit and written assessment | $150 – $400 |
| Detached ADU, design through permits | $18,000 – $35,000 |
| Detached ADU, full build (per square foot) | $350 – $550 |
| Garage conversion, design through permits | $12,000 – $22,000 |
| Garage conversion, full build (per square foot) | $200 – $350 |
| Home addition, design through permits | $15,000 – $30,000 |
| Home addition, full build (per square foot) | $300 – $500 |
| Septic system inspection and capacity report | $600 – $1,200 |
| Septic system expansion or replacement | $15,000 – $45,000 |
| Sewer lateral extension (per linear foot) | $150 – $300 |
| Grading and retaining wall engineering report | $2,500 – $6,000 |
| Fire-resistant siding upgrade (per square foot) | $12 – $22 |
In Los Altos Hills, the price of an ADU or addition is driven hardest by slope, septic, and design-review requirements. A flat one-acre parcel with city sewer can be tens of thousands less than a hillside lot that needs a new septic field and a retaining wall. Whatever the number, we put it in writing before work begins and it does not change at the door.
Neighborhoods We Serve in Los Altos Hills
We work across Los Altos Hills, from the larger estate parcels off Page Mill Road to the hillside lots along Elena Road, La Paloma Road, and the quieter streets near the Los Altos Hills town center. Each area has its own mix of septic systems, slope grades, and design-review expectations, and we route our crew and the site visit around your specific street rather than a generic zone.
- Page Mill Road corridor
- Elena Road and the western ridge
- La Paloma Road area
- Los Altos Hills town center and surrounding streets
- Ravensbury Drive and nearby parcels
Most Los Altos Hills site visits happen within a few business days of your call, because we schedule around the town’s permit office and our existing Hills jobs rather than a regional queue.
Service Area – Cities Near Los Altos Hills
Lodgewick ADU San Jose dispatches crews from the brand’s San Francisco Bay Area office, and Los Altos Hills is one of our core service areas. We also work regularly in San Jose, CA, Palo Alto, CA, Milpitas, CA, and Fremont, CA, so if your project sits near a city line or you own property in two areas, we can coordinate both from the same plan.
Serving Los Altos Hills, CA - Our Local Coverage Area
We’re based in the Los Altos Hills 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 Hills
Plan for design review to take three to nine months depending on the slope, septic capacity, and whether the town requires a geotechnical report with the submittal. The actual build on a Los Altos Hills lot typically runs seven to fourteen months after permits are issued. We give you a written schedule at contract signing and update it weekly, so there are no silent gaps. Call (669) 266-4319 and we’ll walk through your specific parcel.
Most ADU projects in Los Altos Hills go through the town’s design review process because the semi-rural character ordinance applies to new accessory structures, even ones that meet state ADU law. Some neighborhoods also have private covenants. We submit the design package and handle the review comments, and we include that work in the written quote rather than billing it as a surprise line item.
Yes. Every Lodgewick project comes with the 365-Day Done Right Promise in writing before work starts. If something we built fails within that year, we return and make it right at no charge. That promise is part of The Kingswell Guarantee and it applies to every ADU, garage conversion, and home addition we complete in Los Altos Hills. Call (669) 266-4319 to schedule your free estimate.
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 Hills 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
