Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across Corinth
Home additions and ADU construction in Corinth typically run $45,000-$130,000 for an addition and $90,000-$220,000 for a new detached ADU, with permits and inspections included on every eligible job. Most Corinth homes we open up are 1990s-2000s tract builds on slab foundations, and the Blackland Prairie clay under them has been moving for 25-plus years, which means the condition of what’s behind the drywall matters just as much as the square footage you’re adding. We’ve worked the 76210 zip code long enough to know what inspectors will flag and what the dirt will do, and we price that reality into the estimate before we ever swing a hammer. Call (877) 610-1318 for a free, written estimate from a locally run crew that answers its own phone.
Why Barrett & Sons Construction Is Corinth’s Preferred Home Additions & ADU Company
Tom Barrett founded this company in 1998 and his sons run the crews that show up in Corinth. That matters because when you call about a room addition off Swisher Road or a detached ADU near Lake Sharon, the person who answers knows your street, not just a zip code. We’re not a franchise dispatching strangers from three states away. Our crew members are background-checked, uniformed, and carry the Barrett & Sons name on the truck, and a live person answers our phone 24/7, not a voicemail box or an out-of-state call center.
Every Home Additions & ADU job in Corinth starts with an inspection of what’s already there before we talk scope, because we’ve learned the hard way that a 1998 tract home on Blackland Prairie clay has a history. We pull permits and get inspections signed on every eligible job. The permit inspector works for you, not for me, and that’s why we like him. Every price change arrives as a written change order before work proceeds, and every completed job carries our written 90-Day Done Right Promise: if it’s not done right, Tom comes back and makes it right, one call.
Our Home Additions & ADU Services in Corinth
ADU Design & Permitting
Before we frame a single wall on a detached ADU in Corinth, we assess the existing slab and drainage grading on the property. The original 1990s grading on many lots off I-35E has compacted over two and a half decades, so water that used to flow away from the house now ponds against the slab edge. That’s the leading accelerant of foundation movement in this city, and it has to get fixed before a new structure goes up. We handle the design, the permit package, and the inspections, and we write every allowance into the contract in dollars, not vague promises.

New Detached ADU
A new detached ADU in Corinth is a serious foundation job before it’s anything else. The city sits on the Blackland Prairie, where heavy clay soil expands during wet seasons and contracts violently during summer drought, and North Texas swings between both extremes in the same year. We specify foundation work that accounts for that movement, run utilities from the main structure, and build the unit to current code rather than to whatever the original house met in 1999. Expect $90,000-$220,000 depending on size, finish level, and what the property’s drainage situation requires.

Garage Conversion ADU
Converting an attached garage in Corinth usually means working with a slab that was poured as a garage floor, not living space. That slab wasn’t engineered for the same loads, the same insulation, or the same moisture protection as conditioned space, and the drainage grading around it often sends water toward the wall line. We inspect the slab’s movement history and moisture exposure before we commit to a number, then write the conversion scope, including any foundation corrections, into a line-item estimate. Garage conversions in Corinth typically run $30,000-$80,000.

Junior ADU & Interior Conversion
A junior ADU is the most cost-efficient way to add a private living space inside an existing Corinth home’s footprint. We typically convert a large bedroom, a bonus room over the garage, or a finished walk-out area into a self-contained unit with its own entrance, kitchenette, and bath. The work triggers code upgrades for egress windows, electrical load, and smoke separation, which is exactly the stuff national chains underbid and then bill back later. We price it in the original scope, or we bring you a written change order before we touch 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.
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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 Corinth
We install materials you can look up, not mystery brands off a van. For hardscape and drainage work around Corinth ADU foundations, we run Techo-Bloc and Cambridge Pavers products, and we use Quikrete for slab and footing work where the spec calls for it. These are brands with published specifications, and we stock common parts and materials locally so Corinth customers aren’t waiting on a supply house three counties away. Fast turnaround matters when a permit inspection is scheduled and the clock is running.
Common Home Additions & ADU Problems We See in Corinth Homes
- Slab-edge moisture from compacted drainage grading. The original 1990s drainage on Corinth lots has settled over 25-plus years, so water ponds against the slab and rots bottom plates, damages framing, and accelerates clay heave. Any addition or ADU has to address this before framing begins.
- Undersized original wiring behind the drywall. Homes built during Corinth’s 1990s-2000s build-out were wired for the loads of that era. When we open a wall to tie in new framing, we regularly find circuits that can’t carry the expanded load, and the inspector will require an upgrade before sign-off.
- Rotten bottom plates from long-term moisture. On a home addition in the 76210 zip code, our crew opened the wall to tie in new framing and found original 1990s wiring that was undersized for the expanded load and a rotten bottom plate from years of slab-edge moisture. We wrote a change order for upgraded rough-in wiring and repaired the subfloor before inspection sign-off, so the new space passed code without reopening walls.
- Permit-triggered code upgrades nobody bid. Once walls are open, inspectors require bringing old wiring, insulation, and egress windows up to current code. That can add thousands beyond the initial scope, and it’s the single biggest reason an addition quote moves. We write those allowances into the contract in dollars before we start.
Pricing for Home Additions & ADU in Corinth, TX
Here’s what Corinth homeowners can expect to budget, in real numbers, not vague ranges from a national call center.
| Project | Corinth Price Range |
|---|---|
| Home Addition | $45,000-$130,000 |
| ADU Construction | $90,000-$220,000 |
| Garage Conversion | $30,000-$80,000 |
What moves these numbers in Corinth specifically is what’s behind the walls and under the slab. A 1999 tract home that’s seen 25 years of Blackland Prairie clay movement will need drainage corrections and possibly foundation repair before an addition ties in. A detached ADU on the same lot will need its own foundation engineered for that soil. We’re transparent about all of it: every allowance is written into the contract in dollars, every price change arrives as a written change order before work proceeds, and the estimate is free. Call (877) 610-1318 and we’ll walk the property with you and give you a real number.
We Also Serve Cities Near Corinth
Our Home Additions & ADU in Corinth customers live across the 76210 zip code, and we also run crews into Lake Dallas, Flower Mound, Highland Village, and Denton. If you’re a few minutes east of I-35E or up toward the Denton County line, we’re already working in your area. Scheduling is coordinated from our Dallas-Fort Worth office, and the crew that shows up is local to your job site.
Serving Corinth, TX - Our Local Coverage Area
We’re based in the Corinth 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 Corinth
Corinth’s Blackland Prairie clay expands during wet seasons and contracts during summer drought, which means a new detached ADU foundation has to be engineered for movement, not just poured on a standard slab. We assess the existing drainage grading and soil conditions before we ever spec a foundation, because original 1990s grading that has compacted sends water toward new slab edges and accelerates heave within the first wet season. Call (877) 610-1318 and we’ll check your lot before you spend a dollar on plans.
The inspector will require current-code wiring, insulation, and egress windows, plus smoke separation and possibly structural corrections to framing that was undersized by 1990s standards. These upgrades can add thousands beyond the original scope, and they’re not optional once the wall is open. We write those allowances into the contract in dollars before we start, so there’s no surprise invoice at the end. Call (877) 610-1318 for an estimate that includes them.
Because what’s behind the drywall of a 25-year-old Corinth tract home often includes undersized wiring, rotten bottom plates from slab-edge moisture, and framing that doesn’t meet current code. A quote that doesn’t change after the wall is open means the contractor either didn’t look or is planning to bill you later. We write any necessary corrective work as a change order in writing before we proceed, so you approve the number before we touch it.
No, and any contractor who says otherwise is setting you up for a foundation problem. The original garage slab wasn’t poured as living space, and with Corinth’s clay soils, the drainage grading around it has likely shifted enough to pond water against the slab edge. That moisture rots bottom plates and accelerates heave. We address drainage and slab conditions as part of the conversion scope, in writing, before framing begins. Call (877) 610-1318 for a garage conversion estimate that includes it.
It follows the work in stages: deposit at contract signing, then draws tied to foundation completion, framing and rough-in inspection, drywall, and final inspection sign-off. We don’t front-load payments, and every draw is tied to a completed, inspected milestone so you always know what you’re paying for and why. The schedule is written into the contract along with the scope, the allowances, and the 90-Day Done Right Promise. Call (877) 610-1318 and we’ll walk you through one for your specific project.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Corinth since 1998.







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