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 Covington
Air duct sealing in Covington typically runs $450 – $950 for a whole-house system, and most jobs are scheduled within a week of your call. If you’re losing heated air into your attic or pulling greenbelt debris through cracked flex duct, sealing the leaks stops both problems at once.
We serve Covington from our Seattle dispatch office, with crews covering the Kent-Covington corridor daily. That means we’re familiar with the 1990s tract homes off SE 272nd St, the townhome clusters near Covington Woods, and the older split-levels along Wax Road. We know which neighborhoods have buried flex duct in attic insulation, which ones back onto cottonwood groves, and where the shared dryer vent stacks run. Call us at (361) 326-5060 for a free written estimate.
Why Hollis Air Duct Cleaning Is Covington’s Preferred Duct Sealing Company
Hollis has been part of the Garrison Partners family since 2004. Our Duct Sealing team follows The Garrison Standard on every Covington job: arrive inside the quoted window, price in writing before touching equipment, finish by the book, and leave the site clean. No exceptions.
Our technicians are background-checked and uniformed. You get a photo and name before anyone knocks. The price we write down is the price you pay. It does not move at the door. Every repair carries 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.
Phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops. No waiting until Monday for a callback.
Duct Repair in Covington
Duct Repair in Covington usually addresses the flex duct and metal connections in 1990s – 2000s tract homes that have shifted, cracked, or pulled loose from registers after two decades of thermal cycling. The cost typically ranges from $280 – $650 depending on how many runs need attention and whether we need to access buried duct through attic insulation.
Most Covington homes we see have never had their ductwork serviced. Construction debris from the original build, rodent droppings, and accumulated dust sit inside those flex runs. Repairing without cleaning first just traps the contamination. We inspect with a camera before we quote, so you know what’s actually in there.
Disconnected Runs and Collapsed Flex
Flex duct buried in attic insulation gets crushed by workmen walking the joists or compressed by decades of shifting insulation. We find collapsed sections in Covington attics several times a month. The repair involves exposing the damaged run, replacing or reinforcing it, and properly supporting it so it stays open.
Leak Points at Plenum and Register Connections
The metal-to-flex joints at your furnace plenum and at each ceiling register are common failure points. Thermal expansion loosens the straps and tape. We reseat the connections and seal them with mastic, which outlasts foil tape in Covington’s humid attic conditions.
Air Duct Sealing in Covington
Air Duct Sealing in Covington closes the gaps and cracks that let conditioned air escape into your attic, crawl space, or wall cavities. A typical whole-house sealing job runs $450 – $950, with larger homes or systems with extensive flex duct work toward the higher end. We seal after cleaning, never before, because sealing over debris locks contamination in your breathing air.
Our crews use mastic compound and foil-backed tape rated for HVAC applications, applied to clean, dry surfaces. For hard duct, we brush on mastic at every joint and seam. For flex duct, we seal the collar connections and repair any torn outer jacket. The goal is simple: every cubic foot of air your furnace or heat pump produces should reach the rooms you live in.
Greenbelt Debris and Intake Sealing
Many Covington homes back onto greenbelts or the Cedar River trail. Fresh-air intakes and dryer vents pull cottonwood fluff and maple seeds directly into duct runs. We recently sealed the supply and return ducts in a 1998-built home off SE 272nd St near the Cedar River trail, where the blower motor was pulling cottonwood fluff through a cracked flex duct in the attic. After camera inspection, we used negative pressure and agitation tools to remove the debris, then sealed the leaks with mastic and foil tape, restoring proper airflow and stopping the intake of greenbelt debris.
Shared Systems in Townhomes and Condos
Covington’s denser townhome clusters often share dryer vent stacks or have interconnected fresh-air runs. Sealing one unit without checking the shared path can force lint and moisture into neighboring ducts. We map the full system before we seal, and we coordinate with building management when needed.
Trusted Brands We Service in Covington
We carry professional-grade equipment from Nikro, Honeywell, and Aprilaire on every Covington job. Our Nikro negative-air machines create controlled suction that keeps debris contained during cleaning and sealing. Honeywell and Aprilaire filtration products integrate with your existing HVAC system to maintain pressure balance after we’ve sealed the leaks. We stock the mastic, foil tape, and collar fittings that fit the duct sizes common in Covington’s 1990s – 2000s housing stock, so we’re not waiting on parts while your system sits open.
Common Duct Sealing Problems We See in Covington Homes
- Sealing over original construction debris. Many Covington flex ducts still contain drywall dust, wood scraps, and rodent droppings from the 1990s build. Sealing without cleaning first traps those contaminants in your airflow permanently. We camera-inspect and clean before we seal.
- Cheap tape failing in attic humidity. Standard foil tape loses adhesive grip within a season when buried in Covington’s damp attic insulation. We use mastic as the primary sealant, with foil tape only as backup on accessible joints.
- Ignoring shared dryer vent stacks in townhome clusters. Lint from one unit backs into another’s sealed duct run when the shared path isn’t cleared. We inspect the full stack and coordinate with neighbors or HOA when the system is interconnected.
- Cottonwood fluff clogging sealed intakes. Homes near the Cedar River trail pull greenbelt debris through cracked fresh-air ducts. Sealing the leaks stops the debris intake and protects your blower motor from strain.
Pricing for Duct Sealing in Covington, WA
Duct sealing in Covington runs $450 – $950 for a typical single-family home with 8 – 15 runs. Smaller townhomes or partial-system sealing may fall toward $280 – $450. Factors that move the price: how many runs need access through attic insulation, whether we need to remove and replace degraded flex duct, and whether the system requires cleaning before sealing can begin.
We do not quote per-vent prices. We quote one flat price per system, agreed in writing before work starts. That price does not change when our technician arrives. You’ll see the scope, the cost, and the guarantee on paper before we touch your HVAC.
Free estimates. No obligation. Call (361) 326-5060.
We Also Serve Cities Near Covington
Our Duct Sealing in Covington crews also work across the broader Puget Sound region, including Seattle, Spokane, Tacoma, and Vancouver. Scheduling and dispatch are coordinated from our Seattle office, with local technicians serving each metro area.
Serving Covington, WA - Our Local Coverage Area
We’re based in the Covington 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 Covington
These homes are now 25 – 30 years old, and their flex duct has endured decades of thermal expansion, attic humidity, and compression from shifting insulation. Most have never been cleaned or sealed, so leaks have grown and debris has accumulated. Call (361) 326-5060 for a camera inspection and written estimate.
Cottonwood fluff and maple seeds from nearby greenbelts and the Cedar River trail get pulled into cracked ductwork through fresh-air intakes, clogging blower wheels and coating the inside of flex runs. Sealing the leaks stops this debris intake. We address it on nearly every job near the trail.
Yes, and we take extra steps. We map the shared paths, inspect dryer vent stacks that serve multiple units, and coordinate with building management when needed. Sealing one unit without checking the full system can force pressure and contaminants into neighboring ducts.
We use Nikro negative-air machines for contained debris removal, and we seal with professional-grade mastic and foil tape rated for HVAC applications. For filtration integration after sealing, we work with Honeywell and Aprilaire products. These are the same tools commercial crews use, not hardware-store gear.
Signs you need sealing: rooms that never reach temperature, dust pouring from registers even after cleaning, or whistling and rattling at joints. Signs cleaning alone may suffice: visible debris at registers but even airflow and stable temperatures throughout. We camera-inspect and give you a straight answer, with a written price for either service or both. Call (361) 326-5060 to schedule.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Covington since 2004 as part of the Garrison Partners family.




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