A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Westlake Village, CA
Most ADU projects in Westlake Village run between $180,000 and $320,000 for a detached unit before site work, depending on size and finish level. If you’re researching an ADU, home addition, or room addition in Westlake Village, you’re dealing with a city where HOA rules, lot sizes, and terrain vary street by street, and where the right contractor choice changes your timeline and final cost. This page gives you the local picture: what Westlake Village jobs actually cost, why this city’s homes are different, and what you should expect before you commit. Call us at (472) 248-8213 when you’re ready for a written, locked-in price.
Why Westlake Village Homes Are Different
Westlake Village is not a tract of identical 1990s houses. You have older custom homes along streets like Hampshire Road and Lindero Canyon Road sitting beside the lake, mid-century builds in the hills around Triunfo Canyon, and whole neighborhoods governed by HOAs that maintain their own architectural review committees. That matters for your project because an HOA approval can add two to four months to your ADU timeline, and some associations require specific cladding materials or roofline profiles. We walk clients through that paperwork early, because it changes when you can start.
The terrain also shapes the work. Westlake Village lots tilt more often than they sit flat, which means drainage planning and retaining considerations become part of the ADU conversation before foundation work begins. We regularly see projects on hillside lots where the slab or pier system has to account for runoff from the Santa Monica Mountains side of town. A flat-lot price from a contractor who hasn’t walked your specific street is not a real price.
Our Main Westlake Village Services
Most Westlake Village homeowners call us for one of three projects: a full home addition, a detached ADU, or a room addition. Each has its own dedicated Westlake Village page linked below with local pricing and specifics.
Home Addition Contractor in Westlake Village
Home additions here usually mean expanding a first floor outward, adding a second story over an existing wing, or building out a hillside lot where the foundation work gets complicated quickly. Westlake Village’s terrain and older home stock mean we spend more time on structural assessment and drainage planning than a builder working in flatland communities. If you’re considering a larger footprint for your home, see our full Westlake Village pricing and process at Home Addition Contractor in Westlake Village.
ADU Builders in Westlake Village
A detached ADU in Westlake Village usually runs 400 to 1,200 square feet, and the two factors that shape your quote most are your lot’s slope and your HOA’s design standards. We work with prefab lines like Abodu and Dvele when the lot suits them, and we frame custom where the terrain or design review process demands it. For full Westlake Village ADU pricing, timelines, and the permit realities specific to this city, read ADU Builders in Westlake Village.
Room Addition Contractor in Westlake Village
A room addition in Westlake Village tends to be a bedroom, home office, or family room bump-out, often on the same level as the existing house. The local wrinkle is often setback requirements (the required gap between your addition and the property line), which vary by neighborhood and can force a design adjustment mid-planning. We handle those before you spend a dollar on plans. See Room Addition Contractor in Westlake Village for room-by-room Westlake Village pricing.
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 Westlake Village
We have direct experience with Abodu, Cover, Dvele, and James Hardie cladding systems, and we can source parts locally for most projects without long shipping delays. See our brands page for the full list. Choosing the right product line depends on your lot, your HOA, and your budget, and we’ll give you a straight recommendation, not a sales pitch.
Pricing for ADU Company in Westlake Village, CA
Westlake Village pricing varies by square footage, site conditions, and finish level. The table below reflects what we see most often in this market. Every figure includes written allowances, so the price doesn’t quietly drift upward once work starts.
| Service | Typical range in Westlake Village |
|---|---|
| Detached ADU, 400 – 750 sq ft | $180,000 – $260,000 |
| Detached ADU, 750 – 1,200 sq ft | $260,000 – $340,000 |
| Garage conversion ADU | $90,000 – $160,000 |
| Primary suite addition | $120,000 – $210,000 |
| Bedroom addition | $60,000 – $110,000 |
| Bathroom addition | $45,000 – $85,000 |
| Second-story addition | $180,000 – $320,000 |
| Family room bump-out | $70,000 – $140,000 |
| Site work and foundation, hillside | $25,000 – $70,000 |
Hillside lots, retaining walls, and HOA-required design revisions are the three things that push Westlake Village ADU projects toward the top of these ranges. You get a written price before any work starts, and that number is what you pay unless you change the scope yourself.
Neighborhoods We Serve in Westlake Village
We work throughout Westlake Village, from the lake-adjacent streets to the Triunfo Canyon hillsides and the neighborhoods along Thousand Oaks Boulevard. Response time for most homeowners is within the same week for estimates, and we schedule site visits around HOA review windows when needed.
- The Southshore and Northshore lake areas
- Triunfo Canyon
- First Neighborhood and Foxmoor Hills
- North Ranch
- Westlake Trails and surrounding hillside streets
Service Area – Cities Near Westlake Village
If you’re just outside the Westlake Village line, we also handle ADU and addition work in Thousand Oaks, CA, Agoura Hills, CA, Oak Park, CA, and Newbury Park, CA. Terrain and HOA realities vary only slightly across these communities, so the pricing logic on this page generally holds.
Serving Westlake Village, CA - Our Local Coverage Area
We’re based in the Westlake Village 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 Westlake Village
Most Westlake Village homeowners get an estimate visit scheduled within a week of calling. We coordinate from the brand’s Los Angeles office, but crews are local to the area and know Westlake Village HOA and permit processes. Call (472) 248-8213 and a live person answers, day or night.
Yes, and it varies by association. Some Westlake Village HOAs approve quickly, while others have architectural committees that meet monthly and want specific materials or rooflines. We map out your HOA’s process during the estimate, so you know the real timeline before you commit. Call (472) 248-8213 for a straight read on your specific neighborhood.
We handle the permit package for every Westlake Village ADU, addition, and room addition we build, including submissions to the city and responses to plan-check comments. HOA approval runs parallel where applicable. Call (472) 248-8213 to discuss your site, and we’ll tell you what the approval path looks like.
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 Westlake Village Customers Say
"They handled the drawings and the permit paperwork for us. All I had to do was pick the finishes."
- Rosa M."Every crew member was vetted and carried a badge, which matters when they are around your family for months. Tidy site every day."
- Daniel F."Itemized estimate with allowances laid out. Final cost was within a hair of the quote."
- Naomi R.
