Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across Colleyville
Home additions and ADU construction in Colleyville typically runs $45,000-$130,000 for a room addition and $90,000-$220,000 for a detached ADU, and most projects clear permitting in 4-8 weeks depending on HOA and city review. Those numbers reflect the reality of building in one of DFW’s most affluent, nearly fully built-out cities, where custom estate homes from the late 1980s and 1990s now need second stories, garage conversions, and backyard units. We’re Barrett & Sons Construction, and we’ve been owner-operated since 1998. Tom Barrett and his sons run the crews that work in Colleyville, and every job starts with a written scope and a straight answer about what your lot will actually allow. Call (877) 610-1318 for a free estimate.
Why Barrett & Sons Construction Is Colleyville’s Preferred Home Additions & ADU Company
Colleyville homeowners tend to ask the same question before signing anything: will the same person who shook my hand be the one standing in my backyard? For 29 years, the answer has been yes. Tom Barrett’s name, address, and license number are published and verifiable - look it up before you commit to anyone. His sons are on-site most days, not a rotating cast of subcontractors. Ask anyone on your street, or look up the license number yourself.
We’ve worked throughout the 76034 zip code long enough to know that Colleyville’s building department enforces standards that reflect what this city expects: luxury-tier finishes, correct sequencing, and zero tolerance for shortcuts. A national outfit quoting one price on the phone and showing up with another doesn’t survive long in a town where neighbors actually talk. Our reviews from Colleyville customers mention the same things over and over: written change orders before any scope shift, permits pulled and inspections signed on every eligible job, and a live person answering the phone at (877) 610-1318, 24 hours a day.
We also know the local constraints by heart. Setback rules, impervious-cover limits, HOA architectural committees in master-planned communities like Woodbriar and Montclair Park - these decide whether your project is feasible before the first nail moves. We plan for them up front, because an allowance that isn’t on paper is a surprise waiting for a date.
Our Home Additions & ADU Services in Colleyville
Our Home Additions & ADU work in Colleyville covers everything from a single room bump-out to a full detached unit with its own kitchen and bath. These are the four services Colleyville homeowners ask about most.
ADU Design & Permitting
Colleyville’s zoning enforces impervious-cover limits and setback rules that often prevent a teardown or addition from matching the original footprint. That makes pre-permit site analysis the critical first step. We walk the lot, check the impervious-cover ratio against the county’s GIS data, and flag conflicts before you spend a dollar on design work. A permit denied after design fees is the most expensive mistake a homeowner can make, and we see it happen to people who skipped this step.

Garage Conversion ADU
Converting an attached garage into an ADU in Colleyville runs $30,000-$80,000. Many homes built between 1985 and 2005 have three-car garages that adjust well to a one-bedroom unit with a kitchenette and full bath. The catch: Colleyville requires the conversion to preserve the original roofline and brick veneer where visible from the street, and HOAs in communities like Tiverton and Somerset Hills often require architectural committee sign-off before framing starts. We handle both.

New Detached ADU
A detached ADU in Colleyville runs $90,000-$220,000 depending on size, finish level, and site work. Large lots of a third to a half acre give you room, but the city’s impervious-cover limits mean the ADU driveway, pad, and unit footprint all count against your ratio. We plan the site work, drainage, and utility runs as one sequence, not an afterthought. On clay soil, that sequence matters more than people expect.

Junior ADU & Interior Conversion
A junior ADU typically converts an existing wing, bonus room, or oversized primary suite into a separate living area with its own entrance and efficiency kitchen. In Colleyville’s custom homes - many 3,500-6,000+ square feet with non-standard layouts - these conversions often work better than new construction because the square footage already exists. You’re not fighting setback rules; you’re working within walls that are already approved.

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.
Room Additions & Second Story Additions
Second-story additions are the most common large project we take on in Colleyville. This city is essentially landlocked - you can’t add outward forever, so homeowners go up. A 400-700 square foot second-story addition on a 1990s-era custom home typically falls in the $45,000-$130,000 range depending on whether you’re adding bedrooms, a primary suite, or a full bath with premium finishes like Cambria countertops and Kohler fixtures.
The challenge specific to Colleyville: the original framing on late-80s and 90s custom homes is rarely uniform. Different builders, different methods, sometimes three framing approaches in one house. We open walls before we commit to a structural plan, and we pull permits before any structural work begins. The permit inspector works for you, not for me - that’s why I like him.
Trusted Brands We Service in Colleyville
We install materials you can look up, not mystery brands off a van. For hardscape tie-ins on ADU projects - walkways, patios, driveway aprons - we use Belgard and Techo-Bloc pavers, and Quikrete products for concrete work where it makes sense. Our crews stock the most common pavers and concrete mixes for Colleyville jobs, which means fewer supply runs to Southlake or Euless and faster turnaround when your project hits the exterior phase. When a Techo-Bloc paver matches the existing hardscape on a custom estate, we don’t have to special-order it from a yard in Fort Worth. That matters when you’re already months into a build.
Common Home Additions & ADU Problems We See in Colleyville Homes
- Impervious-cover denial after design fees: Homeowners pay an architect for a full ADU or addition design, then watch the permit get denied because the project pushes the lot past Colleyville’s impervious-cover ratio. We check this before design starts. It’s a hundred-dollar analysis that saves thousands.
- Clay soil movement cracking the new work: Colleyville sits on Blackland Prairie clay that shrinks in dry summers and heaves in wet springs. A room addition poured without a foundation specialist’s input will crack within two years. We coordinate with foundation engineers before framing on every addition over 200 square feet.
- Mismatched brick veneer triggering an HOA redo: We’ve seen a master-planned Colleyville neighborhood force a homeowner to tear off and redo a new addition’s brick because the veneer didn’t match the original and the HOA architectural committee never approved the material. We submit samples to the HOA before we order a single brick.
- Summer concrete pours done at the wrong time: Crews from outside the area schedule pours for afternoon because it’s convenient for their route. On 100°F+ Colleyville summer days, that accelerates curing and cracks slabs. We pour in the early morning and use proper curing methods. It’s slower, it’s correct, it’s what the clay soil demands.
Pricing for Home Additions & ADU in Colleyville, TX
Here’s what Colleyville homeowners should expect to pay, based on the work we’ve done across the 76034 zip code.
| Project Type | Typical Colleyville Range |
|---|---|
| Home Addition (room or second story) | $45,000 - $130,000 |
| ADU Construction (new detached unit) | $90,000 - $220,000 |
| Garage Conversion ADU | $30,000 - $80,000 |
What moves the number: site conditions (clay soil, drainage, tree removal), finish level (builder-grade versus Cambria and Kohler), and whether the HOA and city require design revisions. We give every Colleyville homeowner a written, line-item quote before work starts, and every price change arrives as a written change order before a single nail moves. No surprise invoices at the end. Call (877) 610-1318 and we’ll walk your lot and give you real numbers.
We Also Serve Cities Near Colleyville
Our crews work across the northeast Tarrant County corridor. If you’re in Bedford, Hurst, Southlake, or Euless, we bring the same written-scope approach. But for homeowners specifically in Colleyville, we know the city’s impervious-cover rules, HOA expectations, and clay-soil realities better than any outfit dispatching from outside the metro.
Serving Colleyville, TX - Our Local Coverage Area
We’re based in the Colleyville 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 Colleyville
Colleyville’s impervious-cover limits and setback rules often prevent a teardown or addition from matching the original footprint, especially on lots where driveways, patios, and walkways already push the ratio near the cap. You may be able to rebuild on the existing slab, but you cannot always expand outward or add a detached ADU without a variance. We verify the actual impervious-cover ratio on your specific lot before you commit to design fees - call (877) 610-1318 for a free lot assessment.
Yes. In Colleyville communities like Woodbriar, Tiverton, Montclair Park, and Somerset Hills, the HOA architectural committee reviews detached ADUs separately from the city permit process, and their approval is not optional. A city permit does not override HOA covenants. We submit material samples, roofline drawings, and finish specifications to the HOA before ordering anything. HOAs in this city have forced re-dos over mismatched brick; we make sure that never happens to you.
It depends on what the original builder’s warranty still covers and which systems your addition touches. Most structural warranties on homes built in the late 1980s and 1990s have either expired or transfer in limited form. What’s more common: an active HVAC or roof warranty that covers a zone you’re now altering. We phase the rough-in and coordinate inspection sign-off so the new work doesn’t void what remains active. On a 1998 custom estate in 76034, our second-story primary suite addition preserved the homeowner’s active HVAC warranty by sequencing the rough-in around the existing zone controls.
Colleyville sits on Blackland Prairie clay that shrinks and heaves through North Texas’s dry summers and wet springs, causing chronic slab movement. Any addition over about 200 square feet needs a foundation engineer’s input before we pour, and we typically coordinate with a foundation specialist to address existing slab movement before framing any load-bearing wall. Skipping this step means cracked interior finishes and shifting door frames within two years. We don’t skip it.
Most detached ADU permits in Colleyville clear city review in 4-8 weeks, assuming the site plan passes impervious-cover and setback checks and the HOA has signed off. Projects that skip pre-permit site analysis and hit a denial can add 3-6 months in revisions and resubmissions. We front-load the site analysis so your timeline doesn’t blow out. Call (877) 610-1318 and we’ll give you a realistic schedule for your specific lot.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Colleyville and the surrounding northeast Tarrant County communities since 1998.







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