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 Sealing Across Medina
Medina’s mix of century homes around the historic square and mid-century ranches along the lakefront puts unusual strain on ductwork. We’re the crew that knows the difference. Our Duct Sealing team serves Medina from our Seattle coordination office, and we’ve spent years working on the exact systems found here: original galvanized steel with riveted seams in the older neighborhoods, asbestos-wrapped ducts in 1960s builds, and the newer flex-duct installations in subdivisions near Medina’s eastern edge. When ducts leak, you’re heating your crawlspace instead of your bedroom, and your energy bills show it. Call (361) 326-5060 for a free estimate. We’ll give you a written price before any work starts, and we stand behind it with our 365-Day Done Right Promise.
Why Hollis Air Duct Cleaning Is Medina’s Preferred Duct Sealing Company
We’ve earned our reputation in Medina by showing up inside the quoted window and leaving the site clean. That’s The Garrison Standard, and it’s how every Hollis crew operates. Our technicians are background-checked and uniformed, so you know who’s walking into your home before they arrive. Roy Castellanos leads this operation, and he’s built the team on a simple rule: price it in writing, do it by the book, and make it right if it fails. Our phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops, no callback queues. When you call (361) 326-5060, you talk to a human who can schedule your Duct Sealing in Medina or answer questions about what your system needs.
Air Duct Sealing in Medina
Air Duct Sealing in Medina addresses a problem most homeowners don’t notice until their utility bills spike or certain rooms never reach temperature. The process involves finding every leak, gap, and disconnected joint in your duct system, then sealing them with mastic compound or metal-backed tape rated for HVAC use. In Medina’s older homes, we regularly find seams that have worked loose over eighty-plus years of thermal cycling, plus corrosion holes from decades of humid summers and condensation. A typical whole-system seal runs $850 – $1,400 for Medina homes, with smaller partial repairs starting around $350. We price by the system, not by the foot, so your written quote won’t change once we’re on site.
Leak Detection Before Sealing
We pressurize your duct system and use a calibrated manometer to measure pressure loss, then trace every drop with a smoke pencil. This finds leaks behind walls and in crawlspaces that you’d never spot from the vent grille. In Medina’s historic district, we’ve traced leaks to original coal-era cleanout doors that were never properly sealed when systems converted to forced air.
Mastic vs. Tape Applications
We apply duct-sealing mastic, a thick, fiber-reinforced compound that remains flexible for decades, to all longitudinal seams and joints. Foil-backed tape supplements mastic at specific junctions but never replaces it. The tape fails; mastic doesn’t. This matters in Medina’s climate, where summer humidity and winter dryness create constant expansion and contraction cycles.
Duct Sealing Services in Medina
Duct Sealing Services in Medina cover everything from spot repairs on single runs to complete system resealing for whole-house efficiency gains. Most Medina homeowners call us after noticing hot or cold spots, rising energy costs, or dust pulled from crawlspaces through leaky return ducts. Our crews handle the full scope: access panel installation for future maintenance, sealing around floor penetrations, and reconnecting sagging flex duct. A full system seal for a typical 2,000-square-foot Medina home runs $1,100 – $1,600, while targeted repairs on problem zones start at $400. Every job gets a written price before we touch anything, and every seal is covered for 365 days under our Done Right Promise.
Return Duct Sealing
Return leaks are worse than supply leaks because they pull unconditioned air, insulation fibers, and crawlspace dust directly into your blower and living space. We see this constantly in Medina’s mid-century ranches, where original return plenums were built from wall cavities and plywood boxes that have separated from framing.

Supply Register Sealing
The gap between your duct boot and drywall is an invisible energy thief. We seal these with expanding foam and mastic, then verify with a second pressure test. In newer Medina subdivisions, we’ve found builder-grade installations where every boot was left unsealed, adding up to 15 – 20% system leakage.

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.
Trusted Brands We Service in Medina
We seal and repair duct systems connected to equipment from every major manufacturer, and we stock sealing materials from Abatement Technologies and Guardsman for Medina jobs that need fast turnaround. Our equipment roster includes Rotobrush rotary systems for pre-sealing cleaning and Nikro negative-air machines for dust containment during the work. We also source filtration upgrades from Aprilaire when sealing reveals that your system needs better particle control. Having the right materials on hand means we don’t leave Medina jobs half-finished waiting for parts. Roy Castellanos insists on it: arrive prepared, complete the job in one visit when possible, and leave the system tested and documented.
Common Duct Sealing Problems We See in Medina Homes
- Corroded galvanized seams in century homes. The original ductwork near Medina’s historic square has endured decades of condensation cycles. Riveted seams rust through, and we’ve found holes large enough to slip a hand through, dumping conditioned air into wall cavities.
- Asbestos-wrapped ducts in mid-century ranches. Homes built during Medina’s 1960s – 70s expansion often have ductwork wrapped in friable asbestos insulation. We coordinate with certified abatement contractors before sealing these systems, and we never disturb hazardous material without proper containment.
- Disconnected flex duct in crawlspaces. Medina’s humid summers promote mold growth on crawlspace insulation, which weighs down flex duct until it separates from collars. The result is a vent blowing nothing while your utility meter spins.
- Undersized returns choking modern HVAC. Original ductwork in Medina’s older homes was designed for coal-converted gravity systems or early forced air with modest blowers. Today’s higher-efficiency equipment needs more return air than these narrow ducts can deliver, creating pressure imbalances that pull leaks from every seam.
Pricing for Duct Sealing in Medina, WA
Most Medina homeowners pay between $850 and $1,600 for duct sealing, depending on system accessibility and the extent of leakage we find. Small spot repairs on accessible ductwork start around $350. Whole-system sealing for larger homes or systems with significant corrosion can reach $1,800 – $2,200, though this is less common. What drives cost: crawlspace height (tight spaces take longer), the number of duct runs, whether we need to install access panels for reach, and if pre-sealing cleaning is required to remove debris that would prevent mastic adhesion. We also offer Air Duct Cleaning in Medina as a bundled service when both are needed. We do not quote per-vent or per-foot pricing. You get one flat price per system, agreed in writing before work starts. Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Medina
Our crews work throughout the Eastside and Seattle metro, including Medina, Bellevue, Kirkland, Mercer Island, and Seattle proper. Dispatch and scheduling are coordinated from our Seattle office, with local crews serving each area. We also provide Dryer Vent Cleaning in Medina for homeowners who want their full ventilation system checked in one visit. Same standards apply in every city: written price, background-checked technicians, and the 365-Day Done Right Promise.
Serving Medina, WA - Our Local Coverage Area
We’re based in the Medina 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 Medina
We typically schedule Medina appointments within 3 – 5 business days, with some flexibility for urgent comfort issues. Our Seattle coordination office routes crews efficiently to the Eastside, and we confirm your arrival window in writing when you book. Call (361) 326-5060 to check current availability.
Yes, we work throughout Medina, from the century homes around the historic square to the lakefront properties and newer eastern subdivisions. Each area presents different duct challenges, and our crews arrive prepared for the specific housing stock in your neighborhood.
We do not advertise emergency dispatch for duct sealing because it is a scheduled improvement, not an urgent safety repair. However, our phones are answered by a live person 24/7, and we will book you at the first available slot if your system has failed or your home is uninhabitable due to temperature.
Medina pricing falls in the same range as Bellevue and Kirkland, typically $850 – $1,600 for whole-system sealing. Seattle jobs sometimes run slightly higher due to parking and access constraints that don’t apply in Medina’s residential neighborhoods. Your written quote reflects your specific home, not your ZIP code.
Every Medina duct sealing job is covered by our 365-Day Done Right Promise. If any sealed joint fails, any leak reopens, or the work doesn’t perform as specified within one year, we return and make it right at no charge, including a free second visit. This is backed in writing on every job, not a verbal assurance.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Medina and the greater Seattle area since 2004.




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