







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in West Hills, CA
Benson ADU Builders is the ADU company West Hills homeowners call when they want a written price before any work starts. We build accessory dwelling units, home additions, and room additions across West Hills, and every project comes with our 365-Day Done Right Promise in writing. West Hills jobs are different from the rest of the San Fernando Valley: larger lots, older single-story stock, hillside setbacks, and a real mix of HOAs and unincorporated pockets that change how we plan and pull permits. Call (903) 568-7222 to start with a free, no-hassle estimate.
Why West Hills Homes Are Different

West Hills sits at the far western edge of the Valley, pressed against the Santa Susana foothills and the Upper Las Virgenes Canyon Open Space Preserve. That geography shows up in the work. Many homes off Valley Circle Boulevard and Roscoe Boulevard were built in the 1960s and 1970s: single-story ranchers with generous backyards, which is good news for ADU placement, but also hillside grading and drainage requirements that a flat-lot project in the central Valley never has to deal with. The terrain means we spend real time on soil reports and setback compliance before we draw a single ADU line.
Parts of West Hills fall under the West Hills Neighborhood Council and a patchwork of HOAs, particularly in the gated communities north of the 101. Some HOAs require architectural review before an ADU or addition can even go to the city. The climate does its part too: hot, dry summers and the occasional heavy winter rain rolling off the hills. We frame and finish for that reality, using James Hardie cladding and moisture-conscious details that hold up under sun and storm. If you have a mid-century home on a hillside lot in West Hills, your ADU plan looks nothing like a tract-home addition in the flatlands, and we price it that way from the start.
Our Main West Hills Services
Most West Hills homeowners start with one of three conversations: an ADU in the backyard, a home addition that expands the footprint, or a room addition that reworks what they already have. Each has its own page below, and each starts the same way for us: a written price before any work begins.
ADU Builders in West Hills
We are ADU Builders in West Hills, and we build both prefab and site-built accessory dwelling units. On hillside lots, a prefab panel system from Dvele or Mighty Buildings can save weeks of framing time because the modules arrive engineered for the site, not cut on the ground. A detached ADU in West Hills typically starts in the high $100s to low $200s depending on size and utility runs; a garage conversion comes in lower when the shell is already there, and a JADU, or junior ADU, which is a converted bedroom with its own entrance, is the most budget-conscious path. Every option gets a written price and a 365-Day Done Right Promise before a shovel turns.

Home Addition Contractor in West Hills
When a growing family needs a bigger kitchen or a new primary suite, we act as your Home Addition Contractor in West Hills. These are the jobs where West Hills terrain most affects the number: a room bump-out on a flat lot off Sherman Way is straightforward, while a second-story addition on a hillside pad may need additional structural engineering and foundation work. We scope both the same way: a fixed, written price, line-by-line, with no change orders hiding in the wings. Home additions here generally span $150,000 to $450,000 or more, and we tell you exactly where your number lands before you commit to anything.

Room Addition Contractor in West Hills
As your Room Addition Contractor in West Hills, we handle the smaller-but-still-life-changing projects: a home office, a guest room, a den that becomes a media room. In West Hills, room additions often mean working within an existing footprint or extending a wall, which keeps costs tighter than a full home addition. You are usually looking at $120 to $300 per square foot depending on finish level, and on a 300 to 400 square foot room, that is a real, nameable range, not a guess. We put that number in writing before we start, and we honor it.

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 West Hills
Benson ADU Builders builds with the ADU and materials brands homeowners can research themselves: Cover, Dvele, Mighty Buildings, and Boxabl, plus James Hardie cladding. Sourcing from these names means shorter lead times and panels that arrive machined to spec. See our brands for the full lineup.
Pricing for ADU Company in West Hills, CA
| Service | Typical Range in West Hills |
|---|---|
| Junior ADU (JADU), converted bedroom with own entrance | $50,000 – $80,000 |
| Detached ADU, 400 – 600 sq ft, utility runs included | $180,000 – $280,000 |
| Detached ADU, 700 – 1,000 sq ft, higher-end finish package | $300,000 – $450,000+ |
| Garage conversion ADU | $120,000 – $180,000 |
| Prefab panel ADU (Dvele, Mighty Buildings, Cover) | $200,000 – $400,000 |
| Home addition, kitchen or primary suite bump-out | $150,000 – $300,000 |
| Second-story home addition | $250,000 – $450,000+ |
| Room addition, 300 – 400 sq ft, mid-range finishes | $120,000 – $300,000 |
| Room addition, 400+ sq ft, high-end finishes | $300,000 – $450,000+ |
| Permit and architectural plan sets, all service types | $5,000 – $25,000 |
In West Hills, hillside pads and HOA review tend to push prices toward the upper end of these ranges: the engineering and soil work are real costs, not padding. We give you a written, line-item price before any work starts, so the number you approve is the number you pay.
Neighborhoods We Serve in West Hills
Our crews work across the whole West Hills footprint, from Valley Circle Boulevard near the preserve down to the neighborhoods off Roscoe and Sherman Way. We quote every neighborhood the same way: a written estimate, usually within a few days of our first visit.
- Bell Canyon Park
- West Hills Knolls
- Fallbrook
- Valley Circle Estates
- Shadow Ranch-adjacent
Service Area – Cities Near West Hills
We also schedule estimates in the communities right around West Hills, including Canoga Park, CA, Woodland Hills, CA, Calabasas, CA, and Chatsworth, CA. If you live in West Hills or any of these bordering areas, the process is identical: call, get a written price, approve it, and we handle the rest.
Serving West Hills, CA - Our Local Coverage Area
We’re based in the West 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 West Hills

We usually schedule an initial site visit in West Hills within a few days of your call. The written price follows quickly after that, based on what we find: lot slope, access, utility locations, any HOA requirements. Call (903) 568-7222 and we will get you on the calendar.
Yes, in some communities they do. Certain HOAs in West Hills require architectural review before a permit application goes to the city. We identify those requirements during our first visit and build them into your written plan, so you are never surprised by a board rejection halfway through.
Yes. We prepare the plans, submit for permits, and manage the inspections, including any hillside grading or drainage conditions specific to West Hills lots. You get a written price that includes the permitting scope before any work starts, and we keep it updated in real time through our tracking system.
Ready to plan an ADU, home addition, or room addition in West Hills? Call (903) 568-7222 for a free estimate with a written price before any work begins.
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 West Hills Customers Say
"Booked a consult online and met the project manager two days later. Weekly progress updates arrived by text with photos. ADU finished on schedule."
- Hannah W."Clean, quiet crew. They respected the neighbors, kept noise to working hours, and swept the driveway every evening."
- Hope C."Communication was the best part. I always knew what was happening that week without having to ask."
- Dolly N.



