







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Pomona, CA
Benson ADU Builders is an ADU company serving Pomona, CA, and we take a different approach to accessory dwelling units, home additions, and room additions than what most Pomona homeowners have experienced. A Pomona job means working with a specific mix of housing stock: 1920s bungalows near Lincoln Park, mid-century ranch homes in Westmont, and larger 1980s and 1990s homes in Phillips Ranch. You’ll get a written price before any work starts, real-time tracking through the build, and a 365-Day Done Right Promise in writing on every project. If you’re thinking about an ADU in Pomona, call us at (903) 568-7222 to talk through what’s possible on your lot.
Why Pomona Homes Are Different

Pomona’s housing stock spans nearly a century, and that changes how we approach every project. Homes built in the 1920s and 1930s around the downtown core and Lincoln Park neighborhoods often sit on lots with irregular rear yards and older foundations that need a closer look before we anchor a prefab panel or pour a site-built footing. Homes from the 1950s and 1960s in Westmont and the Ganesha Hills area typically have more generous rear setbacks to work with, which can open up a larger ADU footprint without needing a variance. Phillips Ranch, built mostly in the 1980s and 1990s, often has HOA-governed design standards that affect exterior finish choices.
The terrain matters too. Pomona slopes gently upward toward the San Jose Hills on the north side and the I-10 corridor, and several neighborhoods in the northern tier sit on smaller hillside lots. That slope can affect drainage, retaining wall requirements, and how we stage materials on a site. We see more retaining wall and grading work on Pomona jobs than on flat inland lots in nearby cities. The good news is that Pomona’s soil conditions and climate, warm and dry for most of the year with a short wet season, are generally predictable, which helps keep foundation and site work on schedule. When you call, we’ll ask about your specific street and lot so the written price reflects your site, not a generic Pomona average.
Our Main Pomona Services
Most Pomona homeowners reach us for one of three projects: a detached or attached ADU, a full home addition, or a single room addition. Each service has its own Pomona page below so you can get specific pricing and process details without wading through unrelated information.
ADU Builders in Pomona
An ADU in Pomona is a self-contained living unit with its own kitchen, bath, and entry, either attached to the main house or standing on its own in the rear yard. Pomona’s ADU projects break into two paths: prefab, where panels arrive from a factory and are assembled on-site in weeks, or site-built, where every stud is cut and raised on your property. Pomona lots in the flats near Garey Avenue and Holt Boulevard tend to have enough clear rear yard for a detached unit, while tighter lots closer to downtown often work better with an attached conversion of an existing garage or a JADU (junior ADU) inside the main home’s footprint. We build with Abodu, Cover, Dvele, and Mighty Buildings prefab systems, which means you can research the product quality yourself before we ever put a price in writing. ADU Builders in Pomona. That page breaks down Pomona-specific ADU costs, permit considerations, and what a realistic timeline looks like on your street.

Home Addition Contractor in Pomona
A home addition in Pomona expands the main house’s footprint, usually by adding square footage to the side or rear of the structure, and it changes how your home lives as a whole rather than creating a separate unit. On Pomona’s 1940s and 1950s homes, we often see additions that open up a cramped kitchen into a family room or push a primary suite into the rear yard. The important Pomona-specific point is this: older homes in the flatlands often have crawl-space foundations, while newer Phillips Ranch builds sit on slabs, and that affects structural tie-in cost and how we sequence the work. Every addition gets a fixed, written price before we start, so you don’t discover a five-figure change order mid-project. Home Addition Contractor in Pomona. That page covers Pomona pricing, foundation realities, and what additions cost per square foot in this market.

Room Addition Contractor in Pomona
A room addition is a single-space expansion: one new bedroom, a den, an office, or a larger living room added to the existing footprint. This is the most common starting point for Pomona homeowners who need one more real room but aren’t ready for a full addition or an ADU. On Pomona homes with small rear yards, a room addition usually extends out from the back wall rather than the side, and we work around existing utility lines, window openings, and rooflines. The written price you get covers everything we’ll touch, and the 365-Day Done Right Promise means if something isn’t right a year later, we make it right. Room Addition Contractor in Pomona. That page has Pomona-specific room addition pricing and the typical options for matching finish to your home’s existing style.

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 Pomona
We build with and source from Abodu, Cover, and Dvele prefab systems, and we stock replacement parts and panels locally for faster turnaround on Pomona jobs. When you’re choosing a product, you can look up these brands yourself and see exactly what’s going into your build. Our brands page covers the full lineup and what each system does best.
Pricing for ADU Company in Pomona, CA
| Service | Typical range in Pomona |
|---|---|
| Prefab ADU (studio, 400 sq ft) | $120,000 – $180,000 |
| Prefab ADU (1-bedroom, 600 sq ft) | $160,000 – $240,000 |
| Prefab ADU (2-bedroom, 800 sq ft) | $220,000 – $320,000 |
| Site-built ADU (studio, 400 sq ft) | $180,000 – $260,000 |
| Site-built ADU (1-bedroom, 600 sq ft) | $220,000 – $320,000 |
| Site-built ADU (2-bedroom, 800 sq ft) | $300,000 – $420,000 |
| Garage conversion to ADU | $90,000 – $140,000 |
| JADU (junior ADU, interior conversion) | $70,000 – $110,000 |
| Home addition (400 sq ft) | $120,000 – $200,000 |
| Home addition (600 sq ft) | $180,000 – $300,000 |
Hillside lots in northern Pomona and homes in HOA-governed Phillips Ranch can push prices up on the higher end of these ranges because of grading, retaining wall work, and design-review requirements. Whatever the number lands at, it’s the number you’ll pay: your written price is fixed before any work starts, and the only way it changes is if you choose to change the scope.
Neighborhoods We Serve in Pomona
We work throughout Pomona, and our local crews cover the whole city for scheduling and permitting. Typical response for a site visit is within a few business days, and because our scheduling is coordinated from our Los Angeles office with crews stationed locally for Pomona work, you’re not waiting on an out-of-area crew to get to your door.
- Phillips Ranch
- Westmont
- Lincoln Park
- Ganesha Hills
- North Pomona
- Downtown Pomona
Service Area – Cities Near Pomona
Benson ADU Builders also serves homeowners in the cities surrounding Pomona. If you’re in Diamond Bar, CA, Montclair, CA, Chino Hills, CA, or Claremont, CA, the same written-price process and 365-Day Done Right Promise apply to your project, and each city has its own page with local pricing.
Serving Pomona, CA - Our Local Coverage Area
We’re based in the Pomona 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 Pomona

Most Pomona projects start with a site visit within a few business days, followed by a written price in your hands within a week or two after we’ve reviewed your lot and your goals. Actual construction start depends on permit timing, product choice, and our current schedule. Call (903) 568-7222 to get on the calendar for a free estimate.
Some Pomona neighborhoods, especially Phillips Ranch, have HOA design-review standards that can affect exterior finishes, material choices, and even rooflines on ADUs and additions. We handle HOA documentation as part of the project, and we’ll tell you early if your HOA will add review time. Our written price covers coordination with your HOA’s process.
Yes. We work in every Pomona neighborhood from downtown to Phillips Ranch, Westmont, Ganesha Hills, and North Pomona. Because our crews are stationed locally for Pomona jobs and scheduling runs from our Los Angeles office, we can coordinate site visits and build phases across the entire city without the long gaps you get from a far-away contractor.
Thinking about an ADU, home addition, or room addition in Pomona? Call Benson ADU Builders at (903) 568-7222 to schedule a free estimate. You’ll get a written price, a straight answer, and a plan you can hold us to.
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 Pomona 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.



