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 Round Rock
Duct sealing in Round Rock typically runs $450 – $1,200 for a whole-home seal depending on system size and accessibility, and most jobs are scheduled within a few business days. We’re the Duct Sealing crew that serves Round Rock from our Austin office, which means we’re familiar with the subdivisions, the soil, and the builder-grade flex-duct problems that keep showing up in this market. If your upstairs won’t cool or your energy bills climbed after the first summer, call us at (361) 326-5060. We’ll show up in the window we promised, write the price before we touch anything, and stand behind it for a full year.
Why Hollis Air Duct Cleaning Is Round Rock’s Preferred Duct Sealing Company
We’ve been working in Round Rock long enough to know which subdivisions were built with undersized flex runs and which ones have the return plenum sitting right on the slab where blackland prairie soil movement does its damage. Our technicians are background-checked, uniformed, and expected to follow The Garrison Code on every job: arrive inside the window, price in writing, complete the work by the book, leave the site clean. Every repair we make carries our 365-Day Done Right Promise in writing. If the seal fails or the airflow problem returns within a year, we come back at no charge, including a free second visit. No negotiation, no runaround. Phones are answered by a live person 24 hours a day, 7 days a week, so you’re not waiting until Monday to get on the schedule.
Duct Insulation in Round Rock
Duct Insulation in Round Rock is often the missing piece after sealing is done, especially in two-story homes where flex runs snake through 130°F attics and lose so much cooling that the system never reaches setpoint. The job involves wrapping accessible trunk lines and plenums with formaldehyde-free fiberglass insulation, then sealing the vapor barrier with mastic so condensation doesn’t form on the cold duct surface during our humid Central Texas summers. A typical Round Rock home needs $600 – $1,400 in duct insulation work when it’s done alongside sealing, or $800 – $1,800 as a standalone job depending on linear feet and attic accessibility.
Attic Heat Gain in Slab-On-Grade Homes
In Forest Creek, Teravista, and Stone Canyon, the attic air handler sits directly above the living space with no basement buffer. That flex duct is carrying 55°F air through a 130°F ambient environment. Without insulation, you’re paying to cool your attic before you cool your bedrooms. We see this most in homes built 2005 – 2015 where the builder met code minimum but didn’t account for Round Rock’s cooling load.
Condensation and Mold Risk
When cold supply air hits uninsulated metal or poorly wrapped flex in a humid attic, condensation forms on the outside of the duct. That moisture drips onto ceiling drywall or breeds mold in the fiberglass. We insulate to prevent both, using products from Honeywell and Aprilaire that are rated for our climate zone.
HVAC Duct Sealing in Round Rock
HVAC Duct Sealing in Round Rock means finding and closing the leaks that let conditioned air escape into your attic, crawl space, or wall cavities, and it’s usually the first repair we recommend when a homeowner complains of uneven temperatures or rising utility bills. The work involves pressurizing the duct system to locate leaks with a smoke pencil or digital manometer, then sealing accessible joints with mastic and fiberglass mesh, replacing damaged flex runs, and rebuilding collapsed return sections. A typical whole-home seal in Round Rock runs $450 – $1,200, with larger two-story homes or systems with buried ductwork trending toward the higher end.
Return Plenum Separation at the Slab
This is the Round Rock problem we see more than anywhere else in the Austin metro. The return plenum sits on the slab, and as blackland prairie soil swells in wet seasons and shrinks in drought, that concrete moves. The plenum seam opens. Your system pulls attic air, garage fumes, and soil-gas directly into the return. Sealing the trunk lines upstream doesn’t help if this joint is gaping. We check it on every job.
Collapsed Flex Runs Behind Drywall
Builders sized many Round Rock flex runs to the square footage on paper, not to the actual static pressure of the run. Add a tight bend around a truss, and the duct collapses within a few years. Sealing a collapsed run traps the restriction. We cut it out, resize, rerun, and seal the new connection properly.
Trusted Brands We Service in Round Rock
We seal and insulate ductwork connected to every major HVAC brand, and we stock mastic, mesh, and replacement flex from Nikro, Honeywell, Aprilaire, and Abatement Technologies so we’re not waiting on a parts run while your attic air handler bakes. Our Rotobrush rotary systems and Nikro negative-air machines are the same tools commercial crews use in hospitals and schools, and we bring them to your job in Round Rock so the work is done to that standard, not to whatever’s left on the van from yesterday. If your system uses Honeywell media filters, Aprilaire whole-house purifiers, or Guardsman UV lights, we know how to seal around those components without compromising their function.
Common Duct Sealing Problems We See in Round Rock Homes
- New-build construction debris in supply and return ducts. Drywall dust, wood chips, and insulation scraps left at handover get pulled through the blower motor and pack the evaporator coil. The system runs at high static pressure before you ever turn it on, and the leaks you seal are downstream of a coil that’s already struggling.
- Blackland prairie soil movement tearing return plenums apart. Round Rock’s wet-dry cycles swell and shrink the soil under your slab, and that movement transmits directly to the return plenum seam. It’s a failure mode you rarely see in Austin’s older pier-and-beam stock, where the floor structure absorbs the motion instead of the duct connections.
- Undersized flex duct sized to paper square footage, not actual airflow. In Teravista and Stone Canyon two-story plans, the upstairs runs are often too small for the static pressure of the actual routing. The duct sags between trusses, collapses at bends, and starves the upstairs of return air while the downstairs unit cycles normally.
- Attic air handlers cooking flex runs in 130°F summer heat. The return flex collapses from negative pressure when the system can’t pull enough air through a restricted or leaking return path. We got a call from a homeowner in Forest Creek whose two-year-old house couldn’t hold 76°F upstairs while the downstairs unit cycled fine. A camera inspection showed the attic air handler at 130°F and a collapsed return flex run sagging between the trusses; the static pressure readings told us the system was starving for return air. We cut out the crushed section, reran and resized the return, then sealed the plenum seams with mastic and mesh – supply and return ducts both – and the upstairs finally pulled down to setpoint on the first cycle.
Pricing for Duct Sealing in Round Rock, TX
A typical whole-home duct sealing in Round Rock runs $450 – $1,200. Duct insulation adds $600 – $1,400 when bundled with sealing, or $800 – $1,800 standalone. What moves you within that range: system size (single versus two-story), how much ductwork is accessible in the attic versus buried behind drywall, whether we’re replacing collapsed flex runs or just sealing intact ones, and whether the return plenum needs rebuilding at the slab seam. We do not quote per-vent prices. We do not bait you with a low coupon and rewrite the invoice at the door. We inspect, we measure static pressure, we write one flat price per system, and you sign off before we start. Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Round Rock
Our crews work Duct Sealing in Round Rock and the surrounding communities: Pflugerville to the south, Hutto to the east, Georgetown to the north, and Cedar Park to the west. Scheduling and dispatch are coordinated from our Austin office, but the technicians who arrive at your door live and work in this area. They know the subdivisions, the soil, and the building eras.
Serving Round Rock, TX - Our Local Coverage Area
We’re based in the Round Rock 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 Round Rock
Construction debris left in the ducts at handover – drywall dust, wood scraps, insulation – packs your blower motor and evaporator coil, raising static pressure before you ever move in. That pressure collapses undersized flex runs and opens plenum seams faster than normal use would. In Round Rock’s 2015 – 2020 subdivisions especially, the builder-grade flex is often undersized for the actual run length. Call (361) 326-5060 and we’ll inspect with a camera before you assume it’s just dirty filters.
Round Rock’s slab-on-grade subdivisions sit on blackland prairie soil that swells and shrinks with our wet-dry cycles, and that movement tears return plenums apart at the seams – a failure that almost never shows up in Austin’s older pier-and-beam stock, where the floor structure moves instead of the duct connections. Because those original builder-grade flex runs are already undersized and sagging behind the drywall, the leak you’re sealing is usually the second problem, not the first. We check both.
We seal what’s accessible without destructive drywall removal. In Round Rock’s two-story homes, that usually means the attic trunk lines, plenum connections, and flex runs above the top plate. If a run is buried behind drywall and collapsed, we locate it with a camera, explain the access needed, and quote that separately. We do not seal what we cannot see and verify.
Yes, if your return ducts are leaking in the attic. A leaky return pulls unfiltered attic air directly into your system, bypassing the filter entirely. In Round Rock’s heavy spring pollen season, that means your filter loads faster and your indoor air stays dirty. Sealing the return side – especially the plenum seam at the slab – closes that bypass. Call (361) 326-5060 for a pressure test that shows exactly where your system is pulling from.
We pressurize the duct system and measure static pressure at the air handler, then use a smoke pencil or digital manometer to trace leaks at joints, seams, and connections. In Round Rock homes, we always check the return plenum at the slab first – it’s the most common large leak and the one generic duct cleaners often miss. The test takes about 30 minutes and is included in our free estimate.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Round Rock since 2004.