A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Claremont, CA
Adding an ADU in Claremont means working with a city that has its own architectural DNA: older Craftsman and Spanish Colonial homes, tight lot lines near the Village, and neighborhoods where the mature tree canopy affects both solar exposure and crane access. We’re Benson ADU Builders, and we build accessory dwelling units, home additions, and room additions across Claremont with a written price before any work starts. Call (903) 568-7222 and you’ll get a real person, a straight answer, and a plan you can actually price out.
Why Claremont Homes Are Different
Claremont’s housing stock skews older than most of the Inland Empire. A large share of homes north of Foothill Boulevard were built between the 1920s and 1960s, which means foundations are often shallower than modern code expects, and original floor plans rarely have a natural spot for a new ADU. We see a lot of detached garage conversions where the slab needs reinforcement before framing starts. South of the 210, the newer tract homes present the opposite challenge: HOA covenants and smaller rear setbacks that push ADU footprints into specific corners of the lot.
The terrain matters too. Claremont climbs gradually toward the San Gabriel foothills, and lots in the northern neighborhoods often have a noticeable grade change from street to back fence. That slope affects drainage, retaining wall requirements, and how we sequence excavation. We plan for it on day one, not as a surprise change order. And because Claremont summers run hot, we specify wall assemblies and window packages that perform well in sustained heat – something a generic plan set won’t account for.
Our Main Claremont Services
Most Claremont homeowners reach out about one of three projects: building an ADU from the ground up, expanding the main house with a full addition, or converting a garage or underused room into livable space. Each has its own page for Claremont, linked below.
ADU Builders in Claremont
A detached ADU in Claremont is the fastest path to rental income or multi-generational living. We handle the full build, from setbacks and utility connections to final inspection. Claremont’s older lots often need creative placement to preserve driveway access and existing trees, which is exactly where prefab panel systems from Dvele or Cover shine – they arrive as factory-built components that assemble on site with less disruption than traditional framing. ADU Builders in Claremont covers costs, timelines, and which prefab approaches make sense on your lot.
Home Addition Contractor in Claremont
A full home addition in Claremont usually means expanding the kitchen, adding a primary suite, or pushing the living area out toward the backyard. On older homes, we’re often matching rooflines and stucco texture to a 1940s or 1950s original, which takes a practiced eye. We also verify foundation capacity before any plans are finalized. Home Addition Contractor in Claremont walks through what a ground-up addition costs per square foot and how we keep the existing part of the house livable during construction.
Room Addition Contractor in Claremont
Sometimes the job is smaller: a single bedroom, a mudroom, a home office. A room addition in Claremont still requires the same permitting and inspection process as a larger build, but the budget and timeline are tighter. We price these exactly the same way we price a full ADU – line items, written down, before you commit. Room Addition Contractor in Claremont breaks down what a one-room addition runs in this market, including finish levels and how long you should expect the permit to take.
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 Claremont
We build with Cover, Dvele, and Boxabl systems, and we keep common components and parts stocked for faster turnaround on Claremont jobs. When you choose a prefab brand, you can research it independently before we ever set foot on your property. See our brands for the full line.
Pricing for ADU Company in Claremont, CA
| Service | Typical range in Claremont |
|---|---|
| Detached ADU (1 bed, 1 bath) | $180,000 – $260,000 |
| Detached ADU (2 bed, 2 bath) | $240,000 – $340,000 |
| Garage conversion ADU | $120,000 – $180,000 |
| JADU (junior ADU, attached) | $80,000 – $130,000 |
| Prefab ADU (Cover, Dvele, or Boxabl system) | $200,000 – $300,000 |
| Home addition (ground-up, 400 – 600 sq ft) | $160,000 – $250,000 |
| Kitchen addition (180 – 300 sq ft) | $110,000 – $180,000 |
| Primary suite addition (300 – 450 sq ft) | $130,000 – $200,000 |
| Room addition (single room, 120 – 200 sq ft) | $60,000 – $110,000 |
| Room addition (two rooms, 250 – 400 sq ft) | $100,000 – $170,000 |
What pushes a Claremont project toward the top of these ranges? Foundation work on older slabs, upgrades to match a period home’s finish level, and lot slope that adds drainage or retaining-wall scope. Whatever the number, you get it in writing before work begins – no verbal estimate that drifts upward once the crew arrives.
Neighborhoods We Serve in Claremont
We work across the whole city, from the tree-lined blocks near the Claremont Colleges down to the newer subdivisions south of the 210. Response time across Claremont is consistent, with most estimates scheduled within a day or two.
- The Village area and Claremont Colleges neighborhoods
- North Claremont, below the foothills
- Claraboya and surrounding streets near Thompson Creek
- South Claremont, near the Montclair border
- Stone Canyon and the newer builds east of Towne Avenue
Service Area – Cities Near Claremont
Our Claremont crews also cover the cities right next door. If you’re across the border in Montclair, CA, up the hill in La Verne, CA, east in Upland, CA, or down in Ontario, CA, the same written-price process applies. Dispatch and scheduling are coordinated from the brand’s Los Angeles office, and crews serve Claremont locally.
Serving Claremont, CA - Our Local Coverage Area
We’re based in the Claremont 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 Claremont
Most estimates in Claremont are scheduled within 48 hours of your call. We’ll confirm the time in writing, and the person who shows up is background-checked, uniformed, and carrying the plan details you already discussed on the phone. Call (903) 568-7222 and we’ll get you on the calendar.
Claremont follows California state ADU law, which streamlines permits for most detached and attached units. What varies by property is setback enforcement and any HOA rules in the newer subdivisions south of the 210. We pull permits for every job and don’t start work until they’re approved.
Yes. Your written quote is the number you pay unless you ask us to change the scope – and then the change is priced and approved in writing before anything is added. That’s the whole point of a written price before work starts. Call (903) 568-7222 to get yours, free.
Ready to price an ADU, home addition, or room addition in Claremont? Call (903) 568-7222 for a free estimate with a written price and a straight answer.
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 Claremont 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.
