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
Adding an ADU, converting a garage, or building a room addition in Pomona means working with a city that has its own rules, an older housing stock, and a climate that punishes shortcuts. Fielding ADU Builders handles all of it: written pricing before work starts, permits pulled by the book, and a one-year written guarantee on every project. If you’re pricing out an ADU or addition in Pomona, call (361) 315-4177 and we’ll walk you through what your lot can actually support.
Why Pomona Homes Are Different
Pomona’s housing stock is older than what you’ll find in the newer foothill suburbs around it. A large share of the single-family homes here were built between the 1920s and 1960s, which matters when you’re adding square footage: foundations need to be checked, electrical panels often need upgrades, and roof lines rarely match modern truss spacing without some framing work. We see this on nearly every room addition we quote in Pomona.
The climate drives decisions too. Pomona sits far enough inland that summers run hot, so insulation and window placement aren’t details; they’re the difference between a room people actually use in August and one they abandon. The terrain varies by neighborhood. Flat lots dominate south of Holt Avenue and around Westmont, while the areas closer to the 10 freeway and parts of Phillips Ranch have more grade change, which affects drainage and foundation design for backyard ADUs. Setback rules matter everywhere here because so many Pomona lots are modest; when the standard line doesn’t work, we handle the setback variance paperwork with the city.
Permitting reality: Pomona reviews ADU and addition plans through the city’s building division, and accessory structures on lots with existing garages often trigger parking-replacement review. That’s normal. We handle it as part of the price you approve in writing before we start.
Our Main Pomona Services
Homeowners in Pomona call us most often for two kinds of work: converting an existing garage into living space, and building a detached ADU in the backyard. A room addition rounds out the list. Each has its own page with local pricing and process details.
Room Addition Contractor in Pomona
Room additions in Pomona usually mean extending off the back of a mid-century rancher or adding a second story to homes in neighborhoods like Phillips Ranch and Westmont. The work usually involves foundation tie-in, roof integration, and upgrading the existing electrical panel to carry the new load. On Pomona’s flatter lots the addition can go straight back; on sloped lots we plan the foundation so drainage moves away from the house. Written pricing and a permit package are part of every quote. Read the full breakdown on the Room Addition Contractor in Pomona page.
Garage Conversion Contractor in Pomona
Pomona has thousands of detached and attached garages built in the 1940s through the 1970s, and many were never insulated or wired for living space. A garage conversion here typically means new electrical, floor leveling, insulation to meet current energy code, and sometimes a new roof on the garage itself. Parking replacement can come up with the city, and we address it in the permit submission rather than discovering it mid-job. See the process and costs on the Garage Conversion Contractor in Pomona page.
ADU Builders in Pomona
A backyard ADU in Pomona is usually a detached unit of 400 to 800 square feet, and the right build method depends on your lot access and budget. For tighter lots we work with prefab platforms like Abodu and Cover, which ship panels and modules that go up faster than stick-built. For conventional builds, we frame on-site using James Hardie siding and standard California energy details. Every ADU quote includes the site plan, utility connections, and the written price before anything starts. Full details are on the ADU Builders in Pomona page.
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 work with Abodu, Cover, and Dvele on prefab and modular ADU projects throughout Pomona. Parts and finish materials are ordered through our regional suppliers, and because we plan the order early, we avoid the mid-job material delays that stall smaller crews. For a full list of platforms and materials we work with, see our brands.
Pricing for ADU Company in Pomona, CA
| Service | Typical range in Pomona |
|---|---|
| Detached ADU (400 sq ft) | $130,000 – $190,000 |
| Detached ADU (800 sq ft) | $240,000 – $350,000 |
| Garage conversion (attached) | $70,000 – $120,000 |
| Garage conversion (detached) | $90,000 – $150,000 |
| Room addition (300 sq ft) | $105,000 – $150,000 |
| Room addition (500 sq ft) | $160,000 – $230,000 |
| Prefab ADU (installed) | $140,000 – $240,000 |
| Modular ADU (site-built, not prefab) | $170,000 – $280,000 |
What pushes a Pomona project higher is usually the lot: sloped ground, access that blocks equipment, or an older home whose electrical panel needs a full replacement. Those aren’t surprises; we identify them during the walkthrough and put them in the written price. The number you approve on day one is the number on the final invoice, guaranteed by The Garrison Standard.
Neighborhoods We Serve in Pomona
We quote and build across Pomona, including the neighborhoods where the housing stock and lot sizes vary most. The list below covers the areas we see most often, though we serve the full city.
- Phillips Ranch
- Westmont
- North Pomona
- Lincoln Park area
- Ganesha Hills
For most Pomona jobs we can be on-site for a walkthrough within a few business days of your call, and the quote follows in writing.
Service Area – Cities Near Pomona
Fielding ADU Builders also covers the cities around Pomona. If you’re in one of these nearby communities, the same written pricing and one-year guarantee apply: Diamond Bar, CA, Montclair, CA, Chino Hills, CA, and Claremont, CA. Call (361) 315-4177 and we’ll tell you which crew serves your address.
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
After your walkthrough and written estimate, the timeline depends on plan review with the city. Pomona’s building division generally completes ADU plan check within 30 to 60 days for a complete submittal, and we handle the paperwork end to end. Construction typically runs three to six months for a stick-built ADU, less for a prefab unit. Call (361) 315-4177 for a realistic schedule for your lot.
Yes. Every ADU, garage conversion, and room addition in Pomona requires a building permit, and most require plan review. Some projects also need a setback variance if the structure would sit closer to the property line than zoning allows. We prepare and submit everything as part of the job, and the permit cost is in your written quote before work starts.
Every project Fielding ADU Builders completes in Pomona carries The Garrison Standard: a written one-year guarantee covering workmanship defects. If something fails inside those 365 days, we come back and correct it at no charge. Call (361) 315-4177 and a person answers, day or night.
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
"Clear price breakdown. Change orders were all in writing."
- Hal P."Solid job. Cabinet delivery was a week behind but they worked around it."
- Ben G."Insulation, drywall, and finishes were all well done. Feels like part of the house."
- Pete O.
