A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateFast, Reliable ADU Builders Across Los Gatos
Building an accessory dwelling unit (ADU) – a self-contained living space on your existing lot – in Los Gatos typically costs between $180,000 and $420,000 for a full detached unit, with garage conversions landing between $95,000 and $185,000. The town’s hillside overlay zones, historic review requirements, and steeply sloped lots mean your project will face more permitting scrutiny up front than a flatlands build in a neighboring city. That’s why we sequence every Los Gatos project around the geotechnical trigger points, party-wall notice rules, and design review standards specific to this town before we ever put a number in front of you. Call (669) 266-4319 and you’ll get a real person, a written price, and a crew that knows the Almond Grove from the Summit.
Our team serves Los Gatos neighborhoods directly, from the flat streets near Blossom Hill Road up through the hillside parcels off Summit Road and Kennedy Road. We coordinate our scheduling and dispatch from the brand’s San Francisco Bay Area office, but the crews you’ll see on your property are Los Gatos-local, familiar with the town’s permit counter, its noise ordinance, and its design review board. Led by Russ Delmar, our ADU Builders team understands that a tight Los Gatos lot changes everything: staging, access, setbacks, and schedule.
Key Takeaways for Los Gatos Homeowners
- Any ADU over 120 square feet touching a slope steeper than 15% triggers mandatory hillside development review in Los Gatos – the only town in Santa Clara County with this requirement.
- Almond Grove and other historic districts require exterior details to match the original home’s character, from window trim to roof pitch.
- Party-wall notice in Los Gatos must be delivered 10 days before excavation starts on a zero-lot-line project.
- Written pricing comes before any work starts, every time, with no door-change – the price we quote is the price you pay.
Why Lodgewick ADU San Jose Is Los Gatos’s Preferred ADU Builders Company
Los Gatos homeowners have been burned before. They’ve watched a contractor’s quote double after the concrete was poured, or spent three months chasing a follow-up call that never came. Lodgewick ADU San Jose, part of the Kingswell family of home-service companies since 2010, operates differently. Every project runs under The Kingswell Guarantee: a written price before work begins, a defined arrival window, a clean job site, and a written guarantee on every job. If the work isn’t right within 365 days, we come back and make it right – free. That’s the 365-Day Done Right Promise, and it’s in writing before the first nail is driven.
We know the Los Gatos permit process because we’ve moved through it repeatedly. Our team has pulled building permits for detached ADUs, JADUs, and garage conversions across the town, including projects in the Almond Grove historic district that required full design review. Russ Delmar and our local crews have sat through pre-application meetings with the town’s planning staff; we know when a geotechnical report will be triggered and how to sequence it so your timeline doesn’t stall. Background-checked, uniformed technicians show up for every site visit, so you always know who is walking your property. And when you call (669) 266-4319, a live person answers – 24 hours a day, 7 days a week – not a voicemail loop.
JADU in Los Gatos
A JADU (Junior Accessory Dwelling Unit) is the most compact and cost-efficient route to add living space on a Los Gatos lot, converting up to 500 square feet of existing space inside or attached to your primary home – often a spare bedroom, a portion of a basement, or a garage wing – into a self-contained unit with its own kitchenette, sleeping area, and private entrance. In Los Gatos, a JADU conversion typically runs $75,000 to $145,000 depending on whether plumbing rough-ins already exist, how much of the original structure you’re preserving, and whether your home sits in a historic district like Almond Grove where exterior door hardware and window trim must meet design review standards. Homeowners on constrained or steeply sloped lots often choose a JADU because it works within the existing building envelope, avoiding the hillside setback and grading triggers that complicate a detached build.
When a JADU Makes Sense
If your lot has limited flat space – common in the hillside neighborhoods off Old Santa Cruz Highway or in tighter parcels along Los Gatos Boulevard – a JADU keeps the project inside walls you already own. No new foundation, no hillside review, no grading. For a homeowner in the Almond Grove district with a detached garage that’s structurally sound but too small for a full ADU under current code, converting the attached garage wing or an underused interior room into a JADU can bypass the more extensive historic review that a detached ADU addition would trigger. The trade-off is size: a JADU tops out at 500 square feet, and Los Gatos code requires the property owner to live on-site in either the main house or the JADU.
What a JADU Project Involves
We start with a site visit where Russ Delmar or one of our lead builders walks the existing space, checks the foundation and framing, and maps where plumbing and electrical will run. Then we produce a written plan set – including all exterior details if historic review applies – and a line-item price. Construction on a JADU typically takes 3 to 5 months in Los Gatos, depending on the permitting queue and the scope of the mechanical work. Our crews work within the town’s noise ordinance, scheduling louder operations for permitted hours and keeping the job site tidy on narrow streets where a dumpster simply won’t fit; we use smaller bins and scheduled hauling runs instead.
ADU Plans in Los Gatos
ADU Plans are the architectural drawings, structural calculations, and permit-ready documents that get your project from idea to approved building permit – and in Los Gatos, ADU Plans often involve more review than the build itself. A full set of ADU Plans for a Los Gatos project – including site plan, floor plan, elevations, structural engineering, Title 24 energy compliance, and any hillside or historic overlay documentation – typically runs $8,000 to $18,000. That’s higher than flatland cities like San Jose or Santa Clara, because Los Gatos reviews plans through a design review process that may require geotechnical input, fire-hardening details, and elevation drawings that match the original home’s character. You need ADU Plans before you can pull a permit, before you can get an accurate construction bid, and before you can apply for financing tied to the build.
When You Need Full Plans vs. Stock Plans
If your Los Gatos lot is flat and outside any historic district, a stock plan adapted to your parcel can save time and money – our team works regularly with Los Gatos homeowners using pre-drawn designs from manufacturers like Abodu and Cover, then customizes the foundation, utility connections, and site plan locally. If your lot is on a slope over 15% or your home sits in the Almond Grove district, stock plans usually need substantial engineering revision, and in historic zones the exterior elevations must be redrawn to reference your specific home’s trim, roof pitch, and window proportions. Full custom ADU Plans are the safer route in those cases, and they’re what we recommend when we know the town’s review board will be scrutinizing every elevation line.
What’s in a Los Gatos-Ready Plan Set
A plan set that clears Los Gatos review typically includes a soils report or geotechnical letter if hillside development review is triggered, a site plan showing setbacks from the downslope edge (which can shrink buildable area by 15 to 20 feet), fire-resistant material callouts for properties in the wildland-urban interface, and – for Almond Grove parcels – an exterior details sheet matching trim profiles and roof pitch to the original structure. Our team coordinates the structural engineer, the geotech, and the Title 24 consultant so you’re not chasing three separate vendors. Once the plans are approved and the permit is issued, we hand you a written construction estimate that reflects true access cost – not a flat-rate guess based on square footage alone.
Trusted Brands We Service in Los Gatos
We’re hands-on with the prefab and panelized systems that suit Los Gatos lots best. For hillside parcels where a traditional stick-build would require expensive grading and a long foundation cure, we install Abodu and Cover units that are delivered in modules and set on engineered piers or a minimal concrete pad, cutting foundation work dramatically. For homes in fire-prone interface zones east of downtown, we spec James Hardie fiber-cement siding and trim because it carries the Class A flame-spread ratings the town’s wildland-urban interface code requires. And for Almond Grove projects where the historic review board demands authentic wood character, we match Dvele panel finishes and custom trim to the original Craftsman details. We keep local suppliers on rotation and hold material for Los Gatos projects so a backordered panel doesn’t idle your build.
Common ADU Builders Problems We See in Los Gatos Homes
- Slope-triggered plan rejections. A homeowner draws up a detached ADU for a parcel off Old Santa Cruz Highway, files for a permit, and gets a denial because the downslope setback pushes the buildable area 15 to 20 feet in from where they assumed they could build. We sequence the geotech and hillside review first, so the plan we submit matches the plan that gets approved.
- Historic district exterior mismatches. In the Almond Grove district, a studio ADU with modern vinyl windows and a flat metal roof will not pass design review. Exterior details – window trim, roof pitch, siding profile – must reference the original home’s character, and we handle that up front in the plan set so review goes through without a resubmittal.
- Party-wall notice failures. A garage conversion ADU on a zero-lot-line parcel in Los Gatos requires 10 days’ written notice to the adjacent property owner before excavation starts. Skip that step and the neighbor’s objection can stall or kill the permit. We handle the notice, the documentation, and the conversation.
- Right-of-way conflicts on narrow streets. Book a 40-foot dumpster on an Almond Grove street without a right-of-way permit and you’ll get a stop-work order and a $500 fine. We use smaller bins, coordinate hauling runs, and pull the encroachment permits before any equipment arrives.
Pricing for ADU Builders in Los Gatos, CA
Here’s what you can expect to pay for an ADU project in Los Gatos, based on our current estimates and recent builds across the town:
- Studio ADU (under 500 sq ft): $165,000 – $240,000
- One-bedroom detached ADU (500-800 sq ft): $210,000 – $310,000
- Two-bedroom detached ADU (800-1,200 sq ft): $280,000 – $420,000
- JADU conversion (up to 500 sq ft, existing space): $75,000 – $145,000
- Garage conversion to ADU: $95,000 – $185,000
- ADU Plans (full permit-ready set): $8,000 – $18,000
- Prefab or panelized ADU (Abodu, Cover, Dvele): $180,000 – $350,000 installed
Hillside lots run 10 to 25% higher than these ranges because of geotechnical work, deeper foundations or pier systems, and longer material handling. Historic district projects carry an additional design review cost of $2,000 to $5,000 depending on the exterior detail work. We give you a written price before any work starts, and that price holds. No change orders at the door, no “we discovered a problem” upcharge halfway through. Call (669) 266-4319 to schedule a free estimate and we’ll give you a real number in writing.
We Also Serve Cities Near Los Gatos
While this page focuses on Los Gatos, our crews also run projects in Santa Clara, San Jose, Los Altos, and Milpitas. If you’re in one of those cities, we bring the same Kingswell Guarantee, the same written pricing, and the same local-permit familiarity to your build. Each location runs independently, but the standards don’t change.
Serving Los Gatos, CA - Our Local Coverage Area
We’re based in the Los Gatos 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 Builders in Los Gatos
In the Almond Grove historic district, your ADU’s exterior – window trim, roof pitch, siding material, door hardware – must match the original home’s character, and the town’s design review board approves every detail before the permit issues. A modern metal-and-glass studio won’t pass; a gable-roofed unit with Craftsman window proportions and redwood trim will. We handle the design review package so you’re not guessing what the board will accept. Call (669) 266-4319 for a site walk and we’ll tell you what’s buildable on your specific parcel before you spend on plans.
Yes, but it will likely be built on a hillside foundation system – engineered piers, a cantilevered deck, or a stepped stem wall – rather than a conventional slab. Los Gatos triggers mandatory hillside development review for any ADU over 120 square feet that touches a slope over 15%, so a geotechnical report is part of the package. The good news: prefab units from Abodu and Cover are designed for elevated pier foundations, and our crews have set them on Los Gatos slopes where flat area is scarce. The cost runs higher than a flatlands build – factor 10 to 25% more – and we’ll give you that number in writing before anything starts.
Los Gatos requires 10 days’ written notice to the adjacent property owner before you begin excavation or structural work on a zero-lot-line project like a garage conversion. The notice is a legal step – skip it and a neighbor objection can halt your permit. We draft and deliver the notice, document it, and talk directly with the neighbor so the process doesn’t turn into a dispute. Call (669) 266-4319 and we’ll walk you through the sequence on your specific lot line.
Almond Grove streets run as narrow as 18 feet, so we use small bins instead of a full-size dumpster, pull right-of-way permits before any equipment or loader arrives, and schedule deliveries for windows that don’t block the street. We’re inside the town’s noise ordinance on every build, and we set a defined arrival window with our crews so you and your neighbors know when we’ll be on site. The job site is left clean every evening in line with The Kingswell Way – written price first, real arrival window, cleaner than we found it. Call (669) 266-4319 for a free estimate on your Almond Grove project.
Yes. Properties in Los Gatos’s wildland-urban interface zones require fire-resistant exterior materials – typically Class A flame-spread-rated siding like James Hardie fiber cement, ember-resistant vents, and tempered or double-pane windows. The roof assembly also needs a Class A rating. These requirements are baked into your plan set; skipping them gets your permit rejected at review. We spec these materials from the start so the plan matches the code and the review board’s expectations. Call (669) 266-4319 for an exact materials list and written price on your hillside ADU.
Building a JADU or detached ADU in Los Gatos on a constrained lot doesn’t have to be a guessing game. We lay out the geotech triggers, the party-wall steps, the design review details, and the real access costs before you commit. Call (669) 266-4319 to schedule your free estimate – a live person answers, and the price we give you is the price you’ll pay.
Written by Russ Delmar, Owner at Lodgewick ADU San Jose, serving Los Gatos and the surrounding Bay Area.
