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 DeSoto
Duct sealing in DeSoto typically runs $400 – $900 for a whole-home system, with most jobs completed in a single visit once we’ve inspected your attic runs. We dispatch crews from our Dallas-Fort Worth office and regularly work in the DeSoto area, including neighborhoods off Pleasant Run Road, along Hampton Road, and throughout the Windmill Hill and Thorntree communities. If your upstairs registers barely move air or your energy bills have climbed without explanation, the problem is often leaks in the original flex duct runs sitting in your unconditioned attic. Call us at (361) 326-5060 for a free estimate and written price before any work starts.
Why Hollis Air Duct Cleaning Is DeSoto’s Preferred Duct Sealing Company
We’ve been working in DeSoto homes since 2004, and our Duct Sealing in DeSoto crew knows the local housing stock inside and out. The majority of DeSoto’s homes are two-story brick traditional builds from the 1980s through the early 2000s, many with original flex duct and early-generation HVAC systems in the attic. That matters because duct sealing isn’t just about finding holes; it’s knowing where those homes typically fail and why.
Our technicians are background-checked, uniformed, and held to The Garrison Code: arrive inside the quoted window, price in writing, complete the job by the book, and leave the site clean. Every duct sealing job carries our 365-Day Done Right Promise in writing. If the seal fails or the leak returns within a year, we come back and make it right at no charge, including a free second visit. Phones are answered by a live person 24 hours a day, 7 days a week, so you’re not waiting in a callback queue when your upstairs is 85 degrees.
Duct Repair in DeSoto
Duct Repair in DeSoto is most often needed in the city’s 1980s – 2000s two-story brick homes, where original flex duct runs in unconditioned attics have sagged, crushed at tight bends, or completely disconnected from supply plenums. We see this constantly in neighborhoods like Thorntree and along the older sections of Hampton Road, where decades of North Texas heat cycling have degraded duct jackets and caused tape adhesives to fail. A typical duct repair in DeSoto runs $300 – $700 depending on how many runs need attention and whether we need to replace crushed sections entirely.
Collapsed Flex Duct at Attic Bends
Original flex duct was never meant to handle the tight radius turns common in DeSoto’s two-story attic framing. Over time, the wire helix kinks, the duct collapses, and airflow to second-floor rooms drops to a trickle. We cut out the damaged section, install a proper gradual bend with support straps, and seal the connections with mastic rated for attic temperatures.
Disconnected Supply and Return Runs
We regularly find supply or return ducts that have pulled completely free of the main trunk, blowing conditioned air directly into the attic. The homeowner only knows something is wrong because the second floor won’t cool and the electric bill keeps climbing. We reconnect the runs, support them properly, and seal every joint so the connection holds.
Air Duct Sealing in DeSoto
Air Duct Sealing in DeSoto addresses the leaks, gaps, and failed tape joints that develop in aging duct systems, particularly in the city’s large stock of 1980s – 2000s two-story homes with long attic runs. Sealing is the right call when your ducts are intact but leaking conditioned air into unconditioned spaces, forcing your HVAC to run longer and harder. A typical whole-home duct sealing job in DeSoto runs $400 – $900, with the final price depending on system size, attic accessibility, and whether we need to remove old failed sealant before applying new.
Mastic Sealing Over Failed Tape
Foil tape and cheap mastic patches applied years ago have a short life in DeSoto’s attic heat. We remove the old, degraded material, clean the duct surface, and apply fresh duct sealing mastic that flexes with temperature swings and maintains its bond through North Texas summer heat.
Leak Detection Before Sealing
We pressurize the system and use smoke testing or theatrical fog to pinpoint every leak, including the small gaps around register boots and trunk connections that are invisible to the eye. Sealing without finding every leak first is guesswork, and we don’t guess. Our Duct Sealing process is built on locating the problem before we quote the fix.
Trusted Brands We Service in DeSoto
Our crews carry professional-grade equipment from Rotobrush, Nikro, and Abatement Technologies, and we stock filtration and sealing products from Honeywell, Aprilaire, and Guardsman. For DeSoto homeowners, that means we’re not ordering parts from a warehouse three counties away while your attic sits open. We arrive with the mastic, supports, and replacement flex duct sections that DeSoto’s older homes typically need, which keeps most jobs to a single visit and gets your system back online fast.
Common Duct Sealing Problems We See in DeSoto Homes
- Original attic flex duct sagging or crushing at bends. In DeSoto’s two-story brick homes, the long flex duct runs to second-floor rooms often sag between supports or crush where they turn sharply around attic framing. The homeowner feels weak airflow upstairs and assumes the AC is undersized; the real problem is duct obstruction that sealing alone can’t fix until the physical damage is addressed.
- Late-May humidity spikes causing duct sweat and mold growth. DeSoto sits in the Blackland Prairie corridor where the first major humidity surge in late May hits before many homeowners have even switched on their AC. Unsealed or poorly insulated second-floor duct runs in unconditioned attics begin sweating, and mold establishes on the duct jacket before you’ve noticed any comfort issue.
- Decades of dust and allergen accumulation masking leaks. DeSoto’s mature homes often have duct systems that have never been professionally cleaned. The buildup inside the ducts can temporarily seal small leaks from the inside, which means a homeowner who only seals the ducts without source removal may see leaks reopen once the interior is cleaned.
- Cheap foil tape failing within a single season. We’ve peeled off patches of hardware-store foil tape that were applied by well-meaning homeowners or handymen and failed completely after one North Texas summer. The adhesive degrades, the tape curls, and the leak is back. We use mastic and mechanical supports rated for attic conditions, not temporary fixes.
Pricing for Duct Sealing in DeSoto, TX
Whole-home duct sealing in DeSoto typically runs $400 – $900, with most homeowners landing in the $550 – $750 range for a standard two-story home with 15 – 25 runs. Duct repair, when needed alongside sealing, adds $300 – $700 depending on how many sections of flex duct need replacement or reconnection. We give you one flat price per system, agreed in writing before any work starts. No per-vent pricing, no add-ons at the door, no bait-and-switch. The price covers inspection, leak detection, sealing with professional-grade mastic, and a final pressure test to confirm the system holds. Call (361) 326-5060 for a free estimate. We’ll inspect your attic runs, show you what we find, and give you a written number you can count on.
We Also Serve Cities Near DeSoto
Our crews regularly work in Duncanville, Cedar Hill, Lancaster, and Red Oak, bringing the same written pricing and 365-Day Done Right Promise to homeowners across southern Dallas County. Each of these markets has its own housing stock and failure patterns, but the discipline stays the same: show up on time, price it in writing, do it by the book.
Serving DeSoto, TX - Our Local Coverage Area
We’re based in the DeSoto 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 DeSoto
The most common cause is collapsed, disconnected, or badly leaking flex duct in the unconditioned attic, especially in DeSoto’s 1980s – 2000s two-story brick homes where original duct runs have degraded over decades. An HVAC tune-up cleans the coils and checks refrigerant, but it doesn’t address duct integrity; we’ve found completely disconnected supply ducts blowing all their air into attics while the homeowner wonders why the second floor won’t cool. Call (361) 326-5060 and we’ll camera-inspect your attic runs to find the real problem.
That smell is almost always mold growth on sweating duct jackets in your unconditioned attic, triggered by DeSoto’s first major humidity spike before you’ve even turned on the AC. Unsealed or poorly insulated second-floor flex duct runs condensate in the humid attic air, and mold establishes on the duct exterior; when the system finally kicks on, that odor gets pulled into your living space. Proper sealing plus re-insulation of the affected runs stops the sweating and prevents recurrence. Call us for an inspection and written quote.
Duct sealing can reduce dust infiltration if the dust is entering through leaks in return ducts that run through dusty attics, but sealing alone won’t fix dust that’s already accumulated inside the ducts over decades. In DeSoto’s older homes, we typically find that heavy dust loads require a NADCA-standard source removal cleaning first, then sealing to prevent new infiltration. We evaluate both during our free inspection and quote what your specific system needs.
DeSoto’s housing stock presents a specific challenge: original flex duct in unconditioned attics that has been heat-cycled for 20 – 40 years, often with multiple layers of failed tape and mastic from previous patch jobs. The duct surface is dirty, degraded, and sometimes wet from condensation, which means new sealant won’t bond unless we first remove the old material and prep the surface. Cheap shortcuts fail; we do the prep work so the seal holds.
It depends on what we find in your attic. Sealing is sufficient when the ducts are physically intact but leaking at joints and connections; repair is needed when we find crushed, sagging, or disconnected runs that no amount of sealant can fix. During our free inspection, we show you camera footage of what we find and quote exactly what’s needed, no more and no less. The price is written before we start, and it’s covered by our 365-Day Done Right Promise. Call (361) 326-5060 to schedule.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving DeSoto and southern Dallas County since 2004.