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 Flower Mound
Duct repair and sealing in Flower Mound typically costs $280-$890 depending on system count and accessibility, and every job starts with a written price before a single panel comes off. We’re the Duct Repair & Sealing crew that serves Flower Mound from our Dallas-Fort Worth office, dispatching background-checked technicians to neighborhoods like the Estates of Montalcino, Lakeside, and Wellington in marked vans with documented photo records on every visit. Call (940) 240-8552 for a free written estimate, or bring us any competitor’s written quote for a free second opinion under Haven Standard Clause 1.
Why CleanRun Air Duct Cleaning Lewisville Is Flower Mound’s Preferred Duct Repair & Sealing Company
We’ve been in Flower Mound homes since 2013, and the pattern is consistent: a homeowner calls about dust or weak airflow, and our camera finds flex-duct liners detached from register boots, mastic joints cracked from years of attic heat cycling, or construction debris still sitting in supply runs from the builder handover. Our 52,000+ documented jobs include hundreds in Flower Mound subdivisions built during the 1993-2008 master-planned boom, and our crews know the difference between a 2004-era flex-duct layout and the metal trunk systems common in older Lewisville homes nearby.
Every technician is background-checked and uniformed under Haven Standard Clause 3: Verified Crews, and we publish our license number on every page, not buried in a footer. The 365-Day Done Right Promise applies in Flower Mound exactly as it does everywhere we work, backed in writing on every job, not subject to manager approval. Our equipment roster includes Rotobrush, Nikro, and Honeywell systems, professional-grade tools you can look up independently before agreeing to any price.
Our Duct Repair & Sealing Services in Flower Mound

Flex Duct Repair
Flower Mound’s master-planned boom produced homes with 3,500-6,000+ square feet and two or three attic-mounted HVAC systems, almost all fed by fiberglass flex duct. That flex spans long, unsupported attic bays in these big floor plans, and after 15-30 years of 130-140°F summer heat cycling, the inner liner sags at low points, separates from register boots, and traps debris where condensation collects. We reattach detached liners, replace collapsed sections with new flex duct sized to the original CFM load, and install proper support straps at code-required intervals so the valley low-points that caused the failure don’t return.

Mastic Sealant Application
The original mastic applied at construction dries and cracks in Flower Mound attics. We remove failed mastic mechanically, then apply new solvent-based sealant rated for the temperature swings these attics see, brushing it into every joint and seam with a method that achieves full coverage, not just a surface swipe. The work is photographed before and after, and pressure-tested where accessible to confirm the seal holds.

Air Leak Repair
Disconnected runs blowing conditioned air straight into the attic are common in Flower Mound’s 2000s-era subdivisions. At a 2004-built home in the Estates of Montalcino, our tech ran a camera inspection down a second-floor supply run and found the flex-duct inner liner detached from the register boot, dumping conditioned air straight into the attic while the upstairs bedroom never got cold. We reattached and sealed the boot with mastic, re-supported the sagging span with new straps, and confirmed the fix by watching plenum pressure stabilize on the air handler after the blower motor settled down. The homeowner had only called about dust - the real problem was a duct that had been blowing into the attic since the house was new.

Duct Insulation
Where flex-duct insulation has compressed or torn from attic traffic and thermal cycling, we replace or supplement with insulation matched to R-value requirements for North Texas attics. In Flower Mound’s extended cooling season, properly insulated ducts reduce the temperature loss that makes your AC run longer to deliver the same comfort.

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.
Before
AfterTrusted Brands We Service in Flower Mound
Our equipment includes Rotobrush mechanical agitation systems, Nikro negative-pressure extractors, and Honeywell media filters and electronic air cleaners. We stock common flex-duct diameters, register boots, and mastic compounds for Flower Mound’s predominant 2000s-era systems, so most repairs don’t wait on parts orders. For homeowners with Aprilaire or Guardsman whole-house air quality components integrated into their HVAC, we service and seal around these units without disturbing their calibrated airflow.
Common Duct Repair & Sealing Problems We See in Flower Mound Homes

- Builder handover debris still sitting in supply runs. Newer builds in Flower Mound hand over with drywall dust, joint compound grit, and construction debris that was never vacuumed out. The first cleaning is really source removal of builder residue, and that residue often masks disconnected boots or crushed flex that needs repair before sealing can be effective.
- Flex-duct sag at unsupported spans. Long attic bays in big Flower Mound floor plans let flex duct hang in valleys where debris and condensation collect. The liner begins to separate from the register boot, and by the time a homeowner notices weak airflow, the detachment is often years old.
- Heat-cracked mastic at plenum and trunk connections. Attic temperatures regularly exceed 130-140°F in Flower Mound summers, drying and cracking the builder’s original mastic. Conditioned air leaks into the attic instead of the living space, and a standard cleaning visit can uncover several disconnected runs that need repair before they can be sealed.
- Collapsed flex liners from two decades of thermal cycling. In the Estates of Montalcino, Lakeside, and similar 2000s-era subdivisions, we consistently find flex-duct inner liners partially collapsed or detached at register boots. The failure is original construction material reaching end of service life, not a replacement gone bad.
Pricing for Duct Repair & Sealing in Flower Mound, TX
A typical single-system flex-duct repair and sealing job in Flower Mound runs $280-$520. Two-system homes, which are common here, range $450-$780. Three-system jobs or homes with extensive metal trunk repair needs can reach $680-$890. These are whole-system prices, not per-vent teaser rates that balloon once the truck is on your driveway.
What moves the number: the linear footage of ductwork (Flower Mound’s large homes routinely cover three times the footage of older Lewisville properties), accessibility of attic air handlers, whether register boots need replacement or just reattachment, and whether we’re repairing original construction issues or previous repair work that failed. Every price is written before work starts, every time, under Haven Standard Clause 1. No exceptions. Bring us any competitor’s written estimate and we’ll put our number next to it for free.
We Also Serve Cities Near Flower Mound

Our crews work Duct Repair & Sealing in Flower Mound regularly, and we also dispatch to Southlake, Grapevine, Lewisville, and Little Elm from our Dallas-Fort Worth office. The housing stock differs in each city, and our pricing and scope reflect those differences, not a one-size template.
Serving Flower Mound, TX - Our Local Coverage Area
We’re based in the Flower Mound 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 Flower Mound

Yes, and probably for reasons beyond dust. Homes built during Flower Mound’s 1993-2008 master-planned boom often have construction debris still in the supply runs from the builder handover, plus flex-duct liners that have been sagging and separating for 15-20 years. Our camera inspection will show you exactly what’s in there before you decide on any work. Call (940) 240-8552 for a free written estimate.
The most common cause we find in Flower Mound is a detached flex-duct liner at the register boot, dumping conditioned air into the attic instead of the bedroom. The AC runs longer trying to hit the thermostat setpoint while that room stays warm. We locate the disconnect with a camera, reattach and seal the boot, and confirm the fix with pressure readings at the air handler. Call (940) 240-8552 to schedule a camera inspection.
Flower Mound sits in the Cross Timbers zone where mountain cedar peaks December through February and oak and elm follow through spring, giving this area one of the longest heavy-pollen seasons in Texas. If your ducts are leaking at cracked mastic joints or disconnected boots, that pollen is being pulled into the attic and circulated through living spaces every time the blower cycles. Sealing the duct system closes those entry points, and the effect is especially noticeable during the seven-month cooling season when the AC runs almost continuously. Call (940) 240-8552 for a leak assessment.
Negative-pressure extraction means we place the duct system under vacuum using a Nikro collector mounted at the air handler, so loosened debris is drawn out of the ductwork rather than blown into your home. Source removal means we’re physically removing the contamination - construction dust, pollen buildup, degraded liner particles - not just moving it around or masking it with chemical spray. In Flower Mound homes with builder debris still present from 2005, source removal is the only method that actually clears the material. Call (940) 240-8552 and we’ll show you the before-and-after photos from a documented job.
Yes, and it’s why Flower Mound jobs routinely run higher in linear footage than single-system homes in older suburbs. Most 3,500-6,000+ square foot homes here have two or three attic-mounted air handlers, each with its own flex-duct network, and each network needs independent inspection, repair, and sealing. Our written price covers the systems you want addressed, with no per-vent add-ons. Call (940) 240-8552 and we’ll scope the work to your home’s actual layout.
Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Flower Mound since 2013.




Before
After
Before
After