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.
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AfterFast, Reliable Duct Sealing Across Lewisville
Duct sealing in Lewisville typically runs $400 – $950 for a whole-house job, with most homes in the 1,800 – 2,800 square foot range falling between $550 and $750. We dispatch crews from our Dallas-Fort Worth office and regularly work in Lewisville neighborhoods from Castle Hills to the historic corridors near Old Town. Call us at (361) 326-5060 for a free written estimate before any work starts.
We’ve been in Lewisville attics enough to know the pattern. The east-side neighborhoods along the I-35E corridor and near Old Town still carry 1960s-70s original sheet-metal trunk lines with deteriorating flex branch runs. Duct sealing here is often about reconnecting and sealing aged metal-to-flex joints, not just taping new flex in a modern attic. Because those same older attics sit under North Texas’ cedar pollen surge from December through February and 100°F+ summers that run HVAC systems nearly nonstop, loose joints pull attic pollen and hot unfiltered air directly into the supply stream. That’s why a homeowner can change filters monthly and still smell dust when the blower kicks on.
Why Hollis Air Duct Cleaning Is Lewisville’s Preferred Duct Sealing Company
Hollis Air Duct Cleaning has been part of the Garrison Partners family since 2004. Our Duct Sealing in Lewisville work follows The Garrison Standard: arrive inside the quoted window, price in writing before touching anything, complete the job by the book, and leave the site clean. Our technicians are background-checked and uniformed, and our phones are answered by a live person 24 hours a day, 7 days a week.
We don’t compete on the lowest teaser price. We compete on discipline. Every job gets a written price before work begins and is covered by our 365-Day Done Right Promise. If the work fails within a year, we return and make it right at no charge, including a free second visit. Lewisville homeowners tell us the same thing: they called us because the last crew gave a phone estimate that doubled once the van was in the driveway. That doesn’t happen here. The price we write down is the price you pay.
Duct Sealing Services in Lewisville
Duct Sealing Services in Lewisville address the specific failure modes we find in local attics. The job involves pressure-testing the duct system to locate leaks, sealing joints and connections with mastic or metal-backed tape rated for HVAC use, and replacing failed collars or crushed flex runs. Most Lewisville homeowners need sealing when they notice weak airflow at registers, rooms that won’t heat or cool evenly, or dust blowing from vents even after cleaning. A typical whole-house duct sealing in Lewisville runs $400 – $950 depending on system size, attic accessibility, and how many joints have failed.
Metal-to-Flex Joint Repair
The original sheet-metal trunks in Lewisville’s older homes often outlast the flex branches, but the connection points between them don’t. We find collars that have loosened from decades of vibration, tape that has turned to powder, and gaps where unfiltered attic air pours through. We cut out failed connections, install new takeoff collars, and seal with mastic rated for the temperature swings these attics see.
Crushed and Disconnected Run Replacement
Flex duct in Lewisville attics gets crushed by storage boxes, chewed by rodents, or pulled apart by workers crawling past. A crushed 6-inch flex run might deliver half its designed airflow, forcing the blower to run longer and driving up electric bills. We replace damaged sections with new insulated flex, support it properly so it doesn’t sag, and seal every joint.
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.
Duct Insulation in Lewisville
Duct Insulation in Lewisville protects conditioned air from the extreme attic temperatures this market sees. North Texas summers push attic temps past 140°F, and uninsulated or poorly insulated supply ducts lose cooling capacity before the air reaches your rooms. Winter isn’t kind either; those same attics drop below freezing during hard snaps, and heat loss from supply ducts makes furnaces work overtime. Duct insulation involves wrapping exposed metal or replacing degraded flex with properly insulated runs, typically adding $200 – $500 to a sealing job depending on linear footage.
Vapor Barrier Restoration
The outer vapor barrier on older flex duct cracks and flakes in Lewisville attics, exposing the fiberglass insulation underneath. Once that barrier fails, attic moisture soaks the insulation, reducing its R-value and creating a mold risk. We strip damaged outer jackets and install new flex with intact barriers, or wrap metal trunks with foil-faced insulation and sealed seams.
Register Boot Sealing
The connection between ceiling drywall and metal register boots is a common leak point we find in Lewisville homes. Gaps here dump conditioned air into wall cavities or pull attic air through the ceiling. We seal these junctions with fire-rated caulk and mastic, then verify with a smoke pencil that no air movement remains at the boot-to-drywall edge.
Trusted Brands We Service in Lewisville
Our crews carry professional-grade equipment from Rotobrush, Nikro, and Abatement Technologies, the same tools commercial HVAC contractors use in hospitals and schools. For filtration and sealing products, we stock Honeywell, Aprilaire, and Guardsman materials. We keep common collar sizes, flex diameters, and mastic compounds on our vans so Lewisville jobs don’t wait on parts runs. When we find a failed connection in a Castle Hills attic or a crushed run off Mill Street, we fix it that visit.
Common Duct Sealing Problems We See in Lewisville Homes
- Original 1960s-70s sheet-metal trunk-to-flex collars in east-side attics loosen or disconnect. Decades of blower vibration and North Texas thermal expansion work these joints loose, so supply and return ducts pull attic cedar pollen and dust instead of conditioned air. We find this most often in the ranch homes near Old Town and along the I-35E corridor.
- Rodent-chewed and crushed flex runs leak so badly that register airflow drops to a whisper. The blower motor works harder, runs longer, and fails sooner. We replaced three chewed sections in a single attic off Mill Street last spring; the homeowner’s electric bill dropped 18% the next month.
- Spring hail and windstorms crack attic duct connections on older Lewisville homes. A direct hit or even strong wind gust can shift ductwork, opening seams that were sealed years ago. After the 2023 spring storms, we resealed nine homes in Lewisville where hail impact had knocked collars loose or split flex at sharp bends.
- Modern subdivisions like Castle Hills and Valley Ridge need sealing at new construction shortcuts. Even tight flex-duct systems often have unsealed boots, missing end caps, or gaps at the air handler that builders left for “good enough” passing inspection. We pressure-test and seal these before the first cedar season hits.
Pricing for Duct Sealing in Lewisville, TX
Whole-house duct sealing in Lewisville runs $400 – $950 for most residential systems. Small homes under 1,500 square feet with single-zone systems and good attic access sometimes come in at the lower end. Larger homes, multi-zone systems, or attics with crushed runs and multiple failed collars push toward the higher range. Duct insulation adds $200 – $500 depending on how many feet need wrapping or replacement.
What moves the price: the number of joints that need resealing or replacement, whether we can reach all ducts from the attic or need to cut access panels, and whether we’re also cleaning decades of accumulated debris before sealing. We don’t do per-vent pricing or teaser coupons. We give one flat price per system, agreed in writing before work starts. Every estimate is free. Call (361) 326-5060 and we’ll schedule a technician to inspect your attic and hand you a written number.
We Also Serve Cities Near Lewisville
Our crews work throughout the northern Dallas-Fort Worth suburbs. We regularly handle Duct Sealing calls in Lake Dallas, Coppell, The Colony, and Flower Mound, using the same equipment, pricing structure, and 365-Day Done Right Promise we bring to every Lewisville job.
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 About Duct Sealing in Lewisville
Your ductwork is likely pulling unfiltered attic air through loose joints. Lewisville’s east-side neighborhoods have 1960s-70s sheet-metal trunks with deteriorating flex connections; when these loosen, cedar pollen and attic dust enter the supply stream year-round, not just during peak season. We pressure-test the system, locate the leaks, and seal them with mastic and new collars. Call (361) 326-5060 for a free inspection.
Most 1970s ranch homes in Lewisville need sealing and targeted repairs, not full replacement. The original sheet-metal trunks are often still sound; it’s the flex branch runs and metal-to-flex collars that have failed. We inspect with a camera, quote only what’s actually needed, and seal what can be saved. If replacement is necessary, we tell you exactly why and show you the damage. Call (361) 326-5060 for an honest assessment.
The cedar pollen surge from December through February and summer heat that pushes attic temperatures past 140°F accelerate duct degradation and force leaks to matter more. Pollen pulled through gaps coats the inside of ducts and blows into living spaces; hot attic air infiltration makes your AC run longer and harder. Proper sealing blocks both problems. We use mastic rated for these temperature extremes, not hardware-store tape that will fail in the first summer. Call (361) 326-5060 to schedule before the next cedar season.
Yes. Spring storms in North Texas shift ductwork, knock collars loose, and split flex at stress points. After severe weather, we inspect for new leaks even in previously sealed systems. Our 365-Day Done Right Promise covers this: if a storm compromises our work within a year, we return and reseal at no charge. Call (361) 326-5060 after any major storm to schedule a pressure test.
We start with a pressure test using a calibrated fan to measure total system leakage, then locate leaks with smoke pencils or infrared cameras. For sealing, we apply duct mastic with brushes or spray equipment, install new takeoff collars with mechanical fasteners, and replace damaged flex with insulated runs. Our vans carry Rotobrush agitation tools, Nikro negative-air machines, and sealing materials from Abatement Technologies and Guardsman. Call (361) 326-5060 for specifics on your system.
We were called to a 1972 ranch home off Mill Street near Old Town after the homeowner’s family kept sneezing indoors long past cedar fever season. A camera inspection found the original sheet-metal trunk was intact but three flex branch runs had crushed, disconnected collars and rodent-chewed sections in the attic, pulling attic dust and pollen straight into the supply and return ducts. We set the system under negative pressure with HEPA filtration, used agitation tools on the trunk and registers, then sealed the failed collars and reinsulated the vulnerable runs. Symptom calls dropped and the air handler stopped short-cycling against leaks.
Ready to stop breathing attic air? Call Hollis Air Duct Cleaning at (361) 326-5060 for a free written estimate on duct sealing in Lewisville. We’ll inspect your attic, show you what we find, and give you one flat price before any work starts. Every job is backed by our 365-Day Done Right Promise.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Lewisville and the Dallas-Fort Worth Metroplex since 2004.