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 Lewisville
Duct repair and sealing in Lewisville typically costs $280-$650 for most residential jobs, with flex duct replacement running higher when mold remediation is needed. Our crews are dispatched from the Dallas-Fort Worth office and carry full inventories of flex duct, mastic, and metal fittings sized for the tract-home attics that dominate Lewisville’s housing stock. If you’re seeing uneven temperatures between rooms, dust plumes from registers, or musty airflow in lakeside neighborhoods, the problem is usually failed seals or degraded flex duct, not a dirty filter. Call (940) 240-8552 for a written estimate before any work starts.
Why CleanRun Air Duct Cleaning Lewisville Is Lewisville’s Preferred Duct Repair & Sealing Company
We’ve served Lewisville since our founding in 2013, and the documented photo records from those 52,000+ homes include hundreds of attic systems in neighborhoods from Castle Hills to the subdivisions along FM 720. Lewisville customers receive the same standard we apply everywhere: a written price before any panel comes off, background-checked technicians identified by name before arrival, and a 365-Day Done Right Promise backed in writing on every job.
Our dispatch team answers live, 24/7. Crews carry the equipment roster we publish: Rotobrush agitation systems, Nikro HEPA-negative-pressure extractors, and Honeywell airflow verification tools. Every technician works under Haven Standard Clause 3: Verified Crews, with license numbers published on every proposal.
We know Lewisville’s attic geography. The shallow-pitch truss roofs of 1980s and 1990s tract homes leave cramped working conditions that reward technicians who’ve done the crawl before. Our Duct Repair & Sealing team doesn’t guess at boot angles or plenum dimensions; we measure, photograph, and document before quoting.
Our Duct Repair & Sealing Services in Lewisville

Flex Duct Repair
Lewisville’s dominant housing stock, slab-on-grade brick tract homes built 1982-1998, was fitted with flexible duct rated for 15-25 years of service. That ductwork is now 30-40 years old. In eastern shoreline subdivisions near Lake Lewisville, our crews regularly find flex duct with moisture-matted fiberglass and black mold colonization on the inner liner, a combination of lake-driven humidity and attic heat degradation that the dry west side of I-35E rarely produces at the same severity. We replace compromised sections with new insulated flex, secure with mechanical straps (not tape), and verify airflow at each register.

Duct Sealing
Sealing is the fix most Lewisville homes actually need. The Blackland Prairie clay soils beneath Lewisville shift seasonally, stressing duct boot connections and plenum seams until gaps open between the attic and the conditioned space. Our crew pressurizes the system, pinpoints leaks with smoke pencil or digital manometer, then seals with mastic sealant at every joint, boot, and plenum seam. The result is measured: we verify reduced leakage with a second pressure test and include both readings in your documented job record.

Metal Duct Repair
Some Lewisville homes, particularly larger two-stories in Castle Hills and the older sections near Old Town, have galvanized steel trunk lines with spot flex duct branches. Metal ducts don’t degrade like flex, but their seams and joints are equally vulnerable to the soil movement and thermal cycling of North Texas attics. We repair separated seams, replace rusted sections, and transition to new flex where the original design created airflow restrictions.

Duct Insulation & Mastic Sealant
Attic temperatures in Lewisville routinely exceed 140-150°F from June through September. That heat cooks the vapor barrier on aging flex duct until it cracks, letting fiberglass insulation shed into the airstream. We strip compromised insulation, apply fresh wrap rated for the temperature range, and seal every penetration with mastic sealant, not foil tape. Mastic remains flexible across temperature swings and outlasts tape by decades. For homes near Lake Lewisville, we also assess whether the duct layout traps moisture; sometimes repositioning a sagging low point prevents the damp conditions that feed mold.

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.
Before
AfterTrusted Brands We Service in Lewisville
Our trucks stock parts from Rotobrush, Nikro, Honeywell, and Aprilaire, the same brands named in our proposals so you can verify specifications independently. For Lewisville’s mix of original builder-grade systems and aftermarket upgrades, we carry flex duct in R-6 and R-8 insulation values, plenum collars in standard and extended sizes, and mastic sealant rated for the humidity exposure that lakeside attics present. Most repairs don’t require a parts order. The technician who inspects your attic carries what the job needs.
Common Duct Repair & Sealing Problems We See in Lewisville Homes

- Slab movement gaps. Lewisville’s Blackland Prairie clay expands and contracts with moisture, cracking duct boot connections and pulling plenum seams open. We find gaps pulling attic insulation fibers and rodent dander directly into supply air, visible as dust plumes when the blower cycles on.
- Heat-degraded flex duct. Attic temperatures above 140°F wrinkle the inner liner of flex duct until it collapses partially or fully, restricting airflow to distant rooms. The degradation accelerates in Lewisville’s dark shingle attics with minimal ventilation.
- Lake-driven mold colonization. In eastern shoreline subdivisions built on former Corps of Engineers buffer land, humidity from Lake Lewisville keeps duct interiors damp for hours after the AC shuts off. Our crews regularly photograph black mold on flex duct liners that landlocked Carrollton homes of the same vintage rarely exhibit.
- Crushed or kinked runs. Original installations in Lewisville’s 1980s and 1990s tract homes often routed flex duct around truss members with tight bends. Decades of thermal cycling and incidental contact by maintenance workers have compressed these runs into permanent restrictions.
Pricing for Duct Repair & Sealing in Lewisville, TX
A typical duct sealing job in Lewisville runs $280-$450 for a single-system home with accessible attic space. Flex duct replacement, when sections have failed or mold is present, ranges $180-$340 per run depending on length and attic difficulty. Full plenum repair or metal duct seam welding runs $320-$650. These are whole-system prices, not per-vent teaser rates that balloon once the truck is parked.
What moves the number: attic accessibility (shallow truss vs. walkable space), number of compromised runs, presence of mold requiring HEPA-negative-pressure containment, and whether the air handler platform needs modification. We deliver a written price before any work starts, every time, under Haven Standard Clause 1. No exceptions. Bring a competitor’s written estimate; we provide a Free Second Opinion at no cost.
Call (940) 240-8552 for an exact quote. Estimates are free.
We Also Serve Cities Near Lewisville

Our crews work Duct Repair & Sealing in Lewisville and surrounding communities including Flower Mound, Carrollton, Little Elm, and Grapevine. Dispatch is coordinated from our Dallas-Fort Worth office, with local routing that keeps Lewisville appointments on schedule.
Serving Lewisville, TX - Our Local Coverage Area
We’re based in the Lewisville 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 Lewisville

Lake Lewisville creates a localized high-humidity microclimate that keeps duct interiors damp for hours after your AC cycles off, especially in eastern shoreline subdivisions built in the late 1980s on former Corps buffer land. Carrollton sits farther from any major water body; comparable homes there dry out faster, and mold colonization is measurably less severe. The fix is usually replacing compromised flex duct, sealing with mastic to prevent future moisture intrusion, and HEPA-vacuuming under negative pressure to remove settled spores. Call (940) 240-8552 for a written inspection quote.
If your ducts are 30-40 years old, sealing is usually the priority. Cleaning removes debris; sealing fixes the gaps that let debris in. Signs you need sealing first: dust plumes from registers when the blower starts, rooms that never reach set temperature, or energy bills that climbed without rate increases. We test system pressure to quantify leakage before recommending either service. Call (940) 240-8552 for a written estimate.
The expansive clay beneath Lewisville swells when wet and shrinks in drought, shifting slabs and stressing rigid duct connections until gaps open at boots and plenums. Those gaps pull attic air, insulation fibers, and rodent debris into your supply stream. Sealing with mastic closes the pathway; in severe cases we replace damaged boots or relocate connections to more stable framing. Call (940) 240-8552 for a written assessment.
Yes. Attic temperatures exceeding 140-150°F degrade the inner liner and vapor barrier of flex duct faster than manufacturer specifications assume. A 20-year run in Lewisville’s unventilated shingle attic may show the wrinkling, partial collapse, and insulation shedding that cooler climates produce at 30 years. We inspect liner condition with camera and replace sections where the vapor barrier has failed. Call (940) 240-8552 for a written quote.
Yes. Every duct repair that disturbs existing ductwork includes Nikro HEPA-negative-pressure extraction to capture loosened debris before it enters living space. For homes with visible mold, we maintain containment throughout the repair and document the process in your photo record. Haven Standard Clause 2: Containment Protocol requires this on every qualifying job. Call (940) 240-8552 for specifics on your system.
Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Lewisville since 2013.




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