Whole-system duct and dryer vent check with before-and-after photos - you see exactly what came out of your vents
That "$99 whole-house special" is a bait ad - the real number appears once they are in your hallway, or the "clean" is a shop-vac at the register. We photograph the inside of your ducts before and after instead.
Fast, Reliable Duct Repair & Sealing Across Allen
Most duct repair and sealing jobs in Allen run $340-$890 for a whole-home fix, with flex duct replacement at the higher end and targeted mastic sealing at the lower. We dispatch crews to Allen from our Dallas-Fort Worth office, and we typically schedule within 48 hours. Call (940) 240-8552 for a written estimate before any work starts.
We’ve worked in Allen since 2013, and the pattern is consistent: homeowners in subdivisions like Twin Creeks, Watters Crossing, and Star Creek call us after a bedroom stays hot, an energy bill spikes, or a remodel reveals dust pouring from a register. The cause is almost never the HVAC unit itself. It’s the ductwork hidden above the drywall or below the slab, damaged by years of attic heat, foundation movement, or construction debris that should have been cleared before the first owner moved in.
Why CleanRun Air Duct Cleaning Lewisville Is Allen’s Preferred Duct Repair & Sealing Company
Our Duct Repair & Sealing team has documented every job with before-and-after photos since our first year in business. That practice matters in Allen because so many homes here were built during the 1995-2010 production boom, and the duct problems we’re called to fix are specific to that era of construction. We’ve served more than 52,000 homes across North Texas, and Allen represents one of our highest-repeat neighborhoods for duct sealing callbacks, not because our work fails, but because neighbors see the photo record and want the same documentation on their own system.
Tomas Reyes established CleanRun in 2013 under the Haven Standard, and every Allen job still carries the same three non-negotiables: a written price before any panel comes off, a Documented Photo Record of every duct run delivered to the customer, and the 365-Day Done Right Promise backed in writing. Our technicians are background-checked and uniformed under Haven Standard Clause 3: Verified Crews, and they arrive with the customer’s name, address, and scope already confirmed. No “we’ll figure it out when we get there.” No per-vent bait-and-switch. The price on the page is the price on the invoice.
We also offer a Free Second Opinion on any written estimate from another company. Bring a competitor’s quote to us, and we’ll put our number next to it in writing, line item by line item, so you can compare actual scope rather than teaser language.
Our Duct Repair & Sealing Services in Allen

Duct Sealing with Mastic Sealant
Air leaks in Allen homes typically lose 20-30% of conditioned air before it reaches the register. We seal joints, plenum connections, and seams with mastic sealant, a fiber-reinforced compound that remains flexible after curing, unlike foil tape that dries and cracks in attic heat. In Allen’s 150°F attics, mastic outlasts tape by years. A whole-home mastic sealing job in Allen typically runs $340-$520, depending on the number of duct runs and the accessibility of the plenum.

Flex Duct Repair
Flex duct is the standard in Allen’s production homes, and it’s the component that fails first. The vinyl liner sags between supports, kinks at bends, and traps debris. In Watters Crossing and similar subdivisions, we’ve found flex duct runs that were never properly supported during original construction, sagging onto attic insulation where they flatten and restrict airflow. We replace damaged sections with new flex duct, install proper support straps every 4 feet per manufacturer spec, and photograph the repair for the job record. Flex duct repair in Allen typically costs $180-$340 per run, with whole-home replacement reaching $680-$890 for larger two-story plans.

Metal Duct Repair
Older Allen homes and custom builds in areas like Cottonwood Creek sometimes use galvanized metal ductwork. We repair separated seams, corroded sections, and failed dampers. Metal duct requires different sealing compounds and mechanical fastening, and our crews carry the tools for both. Where metal duct has been modified by previous owners or handymen, we often find unsealed tap-ins that leak conditioned air directly into the attic. We document these with photos, seal them properly, and note the repair on the written scope.

Duct Insulation Replacement
Attic temperatures in Allen degrade duct insulation from the outside in. The fiberglass wrap on flex duct compresses and separates from the vinyl core, and the R-value drops to nearly nothing. We replace deteriorated insulation with new wrap rated for North Texas attic exposure, sealed at all seams. This is often paired with flex duct repair, since the same heat that ruins insulation has usually damaged the duct liner beneath it.

What happens when you call
- 1
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.
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AfterTrusted Brands We Service in Allen
Our crews arrive with professional-grade equipment from Rotobrush, Nikro, and Abatement Technologies, brands any homeowner can verify independently. We don’t use shop vacs with brush attachments, and we don’t rent equipment by the day. The negative-pressure extraction systems and camera inspection tools we deploy in Allen are the same units used in commercial settings, maintained on a documented schedule, and operated by technicians trained on that specific model. For sealing and repair materials, we stock mastic compounds, flex duct, and mechanical fasteners matched to the manufacturer specs of the systems we most commonly encounter in Allen’s 1995-2010 housing stock.
Common Duct Repair & Sealing Problems We See in Allen Homes

- Construction dust and drywall debris in newer builds. Allen homes built during the 2000s and 2010s often have supply and return ducts that were never cleaned after construction. Drywall dust, wood chips, and insulation scraps clog flex duct liners and accelerate the need for source removal far sooner than owners expect. We regularly find this debris packed at the first elbow behind the master bedroom register in two-story plans.
- Attic heat degrading flex duct seams. Allen’s North Texas attics exceed 150°F in summer, baking particulates into flex duct insulation and causing the liner adhesive to fail. Seams split. Joints separate. Conditioned air leaks into the attic while the HVAC unit runs longer to compensate.
- Clay soil foundation movement pulling duct boots loose. The expansive Blackland Prairie clay underlying Allen shifts seasonally, stressing duct boot connections at slab-on-grade registers. Local techs regularly find partially detached boots in Allen homes, meaning conditioned air and allergens have been leaking into wall cavities for years before the homeowner notices a comfort problem. This soil-driven failure is far less common in the sandier soils under parts of Frisco to the north.
- Sagging flex duct runs in long two-story attics. The floor plans common in Twin Creeks and Star Creek feature duct runs of 30 feet or more with multiple bends. Without proper support, these runs sag onto insulation, flatten, and restrict airflow to second-floor rooms. The HVAC blower works harder. The room stays hot. The energy bill climbs.
Pricing for Duct Repair & Sealing in Allen, TX
We publish ranges because Haven Standard Clause 1 requires a written price before any work starts, and that price should never be a surprise. Here is what duct repair and sealing costs in Allen’s current market:
- Targeted mastic sealing (whole-home): $340-$520
- Single flex duct run repair/replacement: $180-$340
- Whole-home flex duct replacement: $680-$890
- Duct boot reconnection and sealing: $140-$280 per boot
- Duct insulation replacement: $220-$420 depending on linear footage
These ranges reflect Allen’s housing stock, specifically the prevalence of long flex duct runs through unconditioned attics and the additional labor required to navigate the tight truss spaces common in production homes. We do not price per vent. We price per system, agreed in writing before work begins, with no add-ons discovered after the crew arrives. Every estimate is free, and every estimate includes a written scope. Call (940) 240-8552 to schedule.
We Also Serve Cities Near Allen

Our crews work throughout the northern Dallas-Fort Worth corridor. If you’re in Allen or nearby Plano, McKinney, Richardson, or Carrollton, the same written pricing, documented photo record, and 365-Day Done Right Promise apply. Dispatch and scheduling are coordinated from our Dallas-Fort Worth office, with local crews serving each market.
Serving Allen, TX - Our Local Coverage Area
We’re based in the Allen 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 - Duct Repair & Sealing in Allen

Yes. Drywall debris and construction dust from the original build often remains in flex duct runs for decades, compacting at elbows and behind registers. In Allen’s 2000s-era production homes, we regularly remove material that has been trapped since the first owner moved in. The dust doesn’t break down; it accumulates additional debris over time and restricts airflow. Call (940) 240-8552 for a camera inspection and written estimate.
The Blackland Prairie clay soil beneath Allen expands and contracts seasonally, pulling duct boot connections away from slab floors and wall framing. This creates hidden leaks into wall cavities that no filter upgrade will fix. We reconnect the boot, seal the joint with mastic, and photograph the repair for your job record. Most boot repairs in Allen run $140-$280 per location.
Attic temperatures above 150°F degrade the adhesive in flex duct seams and bake particulates into the insulation wrap. Over time, the liner splits and the insulation separates from the core. We replace damaged sections with new flex duct rated for attic exposure, install proper support straps, and seal all joints with mastic that remains flexible in heat. Call (940) 240-8552 for an inspection.
Often yes. In Twin Creeks, a two-story production home built in the early 2000s had a second-floor bedroom that never seemed to cool, even after a new air handler. Our tech ran a camera inspection and found a flex duct run in the 150°F attic had sagged and kinked behind a bend, while the register boot below had separated from the drywall as the foundation shifted. We reconnected the boot, sealed the joint with mastic, and re-supported the run, and the supply static pressure dropped enough that the blower motor was no longer working overtime. The room cooled properly for the first time in years.
It starts with a written price before any work begins, includes a camera inspection of every duct run, and ends with a Documented Photo Record showing before-and-after conditions inside the ducts. For Allen homes, it specifically addresses flex duct support, mastic sealing at all joints, and boot reconnection where foundation movement has caused separation. The crew operates under Haven Standard Clause 3: Verified Crews, and the work is backed by the 365-Day Done Right Promise in writing. Call (940) 240-8552 to schedule your free estimate.
Ready to stop losing conditioned air to your attic and walls? Call (940) 240-8552 for a free written estimate on duct repair and sealing in Allen. We’ll inspect your system, show you what the camera finds, and give you a flat price per system before any work starts. No per-vent pricing. No add-ons. Just documented results backed by our 365-Day Done Right Promise.
Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Allen since 2013.




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