Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across Beaumont
Most Beaumont homeowners reach a point where the house they bought in 2016 during the boom simply doesn’t fit anymore. A new baby, aging parents moving in, a remote-work setup that outgrew the spare bedroom. The tough part is figuring out whether to add on, build an ADU, or move. Our Home Additions & ADU team has walked through hundreds of Beaumont homes in Tournament Hills, Sundance, and Fairway Canyon, and we’ll tell you straight: a well-planned addition or ADU in Beaumont usually costs between $45,000 and $130,000 for an addition, and $90,000 to $220,000 for a detached ADU. That’s real money, which is why we put every scope, every allowance, and every change order in writing before work starts. Call (877) 610-1318 and Tom Barrett will give you an honest read on what your lot and your budget can handle.
Why Barrett & Sons Construction Is Beaumont’s Preferred Home Additions & ADU Company
Tom Barrett founded this company in 1998 and his sons run the crews today. That matters in Beaumont because this is a town where people still talk to their neighbors. Ask around Sundance or Four Seasons about who actually shows up, who answers the phone, and who stands behind their work when something needs fixing. We’re an owner-operated shop, not a franchise dispatching strangers to your door. Tom’s name, address, and license number are published, and you’re welcome to look us up before signing anything.
Beaumont homeowners tell us the same story again and again: a national outfit quoted one price on the phone, then handed them a different bill once the slab was poured. Our contract eliminates that entirely. The 90-Day Done Right Promise is written on every job. If something isn’t right, Tom comes back and makes it right, one call. That’s it.
We know the Beaumont building department, we know which HOA architectural review boards in the master-planned communities are strict about ADU setbacks and exterior finishes, and we know the wind-load requirements that catch out-of-area contractors off guard. That local knowledge keeps your permit moving and your inspection signed.
Our Home Additions & ADU Services in Beaumont
ADU Design & Permitting
Accessory dwelling units in Beaumont follow California state ADU law, but Beaumont’s building department has its own checklist for setbacks, utility connections, and fire access on the hillside lots around the 92223 corridor. We handle the full design package, HOA submittal if you need it, and all permits. The permit inspector works for you, not for us, and that’s exactly how we like it. A standard 800-1,200 square foot detached ADU in Beaumont runs $90,000 to $220,000 depending on site prep and finishes.

Garage Conversion ADU
Converting an attached or detached garage is often the fastest path to rental income or a mother-in-law suite, especially on Beaumont’s newer tract lots where the garage already sits on a poured slab. Expect $30,000 to $80,000 for a garage conversion in Beaumont. We’ll assess your existing foundation, tie into the home’s electrical panel with proper permits, and bring the space up to California’s energy-efficiency standards for ADUs. We can also discuss Windows & Doors in Beaumont if your conversion needs upgraded openings. In neighborhoods like Tournament Hills, where many garages face narrow alleys, we also coordinate with the city on access requirements.

New Detached ADU
A detached ADU gives you clean separation from the main house, which is what most multigenerational families in Beaumont actually want: privacy for adult kids or aging parents, with everyone still on the same lot. We’ve built these on the larger lots in Cherry Valley and on Beaumont’s hilltop pads with westward views. The San Gorgonio Pass wind matters here. A detached ADU’s roof system has to be engineered for uplift loads that lower-elevation Inland Empire cities like Redlands never see, which is why our Beaumont Roofing expertise matters. We size the fasteners, the underlayment, and the structural ties accordingly, and we put that in writing.

Junior ADU & Interior Conversion
A JADU, or junior accessory dwelling unit, is typically a bedroom converted into an independent living space with its own entrance and cooking facilities. California caps JADUs at 500 square feet, and Beaumont’s newer floor plans often have a ground-floor bedroom that converts cleanly. This is the most affordable ADU path, and many Beaumont homeowners start here before committing to a full detached build. We’ll tell you honestly whether your floor plan works for a JADU or whether the money is better spent on a full addition.
If you’re already thinking about reworking the main house alongside an ADU, we also handle Kitchen Remodeling in Beaumont and Bathroom Remodeling in Beaumont, so one crew can manage the entire project start to finish.

What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Beaumont
When we pour concrete flatwork for an addition site or run paver driveways and patios alongside a new ADU, we use Belgard and Techo-Bloc products that you can walk into a supply yard and verify yourself. No mystery brands off a van. For hardscape elements like walkways and retaining walls around an addition, we also work with Cambridge Pavers and Quikrete products. These are materials with published specifications and warranties, which matters when you’re investing six figures in a Beaumont home and want to know exactly what’s holding it up.
Common Home Additions & ADU Problems We See in Beaumont Homes
- Foundation movement on expansive clay. Riverside County’s shrink-swell soils are notorious, and Beaumont’s rapid post-2000 build-out means many slabs were poured and homes framed before the ground had fully stabilized. In Sundance and Tournament Hills especially, we regularly see slab cracks and stucco separation that affect how an addition must be tied into the existing foundation. We won’t attach new structure to a compromised slab without addressing it first.
- Wind-load underspecification. The San Gorgonio Pass is one of the windiest corridors in the continental US. Roof panels, ridge caps, and exposed west-facing walls on Beaumont’s new subdivisions take a beating. When we design an addition or ADU here, we specify fastener patterns and underlayment that exceed what lower-elevation Inland Empire cities require. It’s not optional. Insurance claims across 92223 after wind events prove it.
- HOA architectural review delays. Most of Beaumont’s housing stock sits inside master-planned communities with active HOAs. That means exterior modifications, ADU placement, even paint colors for an addition need approval before permits. We’ve worked with the boards in Four Seasons, Sundance, and Fairway Canyon enough to know what gets flagged and what sails through. We handle the submittals so you don’t have to decode the CCRs yourself.
- Stucco cracking from temperature swings. Beaumont sits around 2,500 feet in elevation, and the day-night swing here is substantially wider than in Redlands or Moreno Valley. That expansion and contraction cycle opens up stucco cracks and caulk failures faster. When we tie an addition into an existing Beaumont home, we detail the transition joints for that movement, because sealing them like a coastal house will fail within two seasons.
Pricing for Home Additions & ADU in Beaumont, CA
Let’s talk real numbers, because you deserve to walk into this with your eyes open. A single-room addition in Beaumont runs $45,000 to $130,000. A garage conversion ADU runs $30,000 to $80,000. A new detached ADU runs $90,000 to $220,000 based on size, site prep, utility runs, and finishes. Here’s what moves the number: whether your lot needs grading or retaining walls, how far the new structure sits from the electrical panel and sewer line, whether the HOA requires specific exterior materials, and what kind of foundation work your existing slab needs. We write every allowance and every scope item on paper before work begins. If the price changes, you get a written change order first. No surprises. Call (877) 610-1318 for a free estimate, and ask about our 10% senior and veteran discount.
We Also Serve Cities Near Beaumont
In addition to working throughout Home Additions & ADU in Beaumont, our crews regularly take on projects in Cherry Valley, Banning, Calimesa, and Yucaipa. If you live just outside the 92223 ZIP and are wondering whether we’d come out, the answer is almost always yes. The same crew, the same written change orders, and the same 90-Day Done Right Promise apply no matter which side of the city line you’re on.
Serving Beaumont, CA - Our Local Coverage Area
We’re based in the Beaumont 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 - Home Additions & ADU in Beaumont
We schedule free estimates across Beaumont every week, and because our scheduling is coordinated from the Inland Empire office, we can typically get to any 92223 address within a few business days. Call (877) 610-1318 and a live person will answer, 24 hours a day, 7 days a week. No voicemail maze, no out-of-state call center.
Yes. We work throughout Beaumont including Sundance, Tournament Hills, Fairway Canyon, Four Seasons, and the older pockets near Beaumont Avenue. If you’re in the 92223 ZIP, we cover it. That includes the hillside lots and the newer tract subdivisions on the west side of town where wind exposure is highest.
Only if the scope changes, and any change arrives as a written change order before work proceeds. You approve it in writing first. That’s the rule we’ve operated under since 1998. An allowance that isn’t on paper is a surprise waiting for a date, and we don’t do surprises. Call (877) 610-1318 for an exact quote, and the estimate is free.
Yes. Most of Beaumont’s housing stock sits inside HOA-governed communities, and we prepare and submit architectural review packages for additions and ADUs as part of the design phase. We know what the boards in Sundance, Four Seasons, and Fairway Canyon typically require, and we build those requirements into the plan from day one so you don’t get a rejection letter two months in.
Every job we complete comes with the 90-Day Done Right Promise, written on the contract, not buried in fine print. If something isn’t done right, call Tom and he comes back. Beyond that, the materials we install, like Techo-Bloc pavers and Belgard hardscape products, carry their own manufacturer warranties that you can register in your name. We put all of that in writing before the first nail moves.
Ready to talk about your Beaumont home addition or ADU? Call (877) 610-1318 today for a free, no-pressure estimate. Tom Barrett will give you an honest answer about what makes sense for your lot, your budget, and your family. We’ve been doing this since 1998, and we’ll be here long after the job is done.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Beaumont and the surrounding Inland Empire communities since 1998.







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