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.
Before
After
Before
After
Before
AfterFast, Reliable Duct Sealing Across East Renton Highlands
East Renton Highlands homeowners with stuffy upstairs rooms and rising energy bills usually have one thing in common: leaky ductwork that’s been hiding in attics and crawl spaces since the house was built. We’re Hollis Air Duct Cleaning, and our Duct Sealing crews work the plateau’s western edge regularly, from the 1970s ranches near May Creek to the two-story homes climbing toward the Cascade foothills. Dispatch and scheduling run through our Seattle office, but the technicians who arrive at your door know this microclimate, know the housing stock, and know that a damp attic here degrades flex duct differently than it does in drier parts of King County. If your system runs long heating cycles through our wet winters and still can’t balance temperatures, call us at (361) 326-5060. We’ll inspect the ductwork and give you a written price before any work starts.
Why Hollis Air Duct Cleaning Is East Renton Highlands’s Preferred Duct Sealing Company
We’ve been in business since 2004 as part of the Garrison Partners family, and our reputation in East Renton Highlands is built on showing up inside the window, pricing in writing, and leaving the site clean. That’s The Garrison Standard, and it applies to every job we run on the plateau.
Our technicians are background-checked and uniformed. You know who’s walking into your home before they arrive. And when we say we’ll be there, we’re there, because a no-show in East Renton Highlands means another day of unbalanced airflow and wasted energy.
Phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops, no callback queues, no waiting until Monday to schedule.
The 365-Day Done Right Promise backs every repair we make. If the work fails within a year, we come back and make it right at no charge, including a free second visit. That’s not a slogan; it’s written on every job.
HVAC Duct Sealing in East Renton Highlands
HVAC Duct Sealing in East Renton Highlands addresses the leaks, gaps, and degraded connections in forced-air systems that waste heated and cooled air before it ever reaches your rooms. Because East Renton Highlands sits cooler and wetter than Renton proper and stays closed up through roughly 150 rainy days a year, duct systems here run longer heating cycles and pull in damp temperate-rainforest dust and pollen from the Sammamish Plateau’s western edge – so the sealing failures we find are as much moisture-driven as they are mechanical. The 1980s two-story homes on the plateau’s east side often still carry the original foil-tape-wrapped flex duct in the attic, which degrades in the damp attic humidity and collapses or tears, creating the pressure imbalances that make upstairs rooms stuffy. A typical HVAC duct sealing job in East Renton Highlands runs $450 – $850 for a whole-system seal, depending on accessibility and the extent of damage we find.
When Sealing Is the Right Fix
Sealing makes sense when the ductwork is structurally sound but leaking at joints, seams, or connections. We use mastic sealant and mechanical fasteners, not tape, because tape fails in damp attics. The goal is restoring designed airflow without replacing intact runs.
Heat Pump System Considerations
Many East Renton Highlands homes run heat pumps or electric forced-air rather than gas furnaces. These systems operate at different static pressures and blower profiles. Our sealing work accounts for this, matching sealant application and register balancing to your actual equipment, not a generic gas-furnace assumption.
Duct Repair in East Renton Highlands
Duct Repair in East Renton Highlands goes beyond sealing to fix physical damage: crushed runs, torn flex duct, disconnected boots, and corroded galvanized sections that no longer hold air. The older two-story homes on the plateau’s east side, built in the 1980s, often still have the original foil-tape-wrapped flex duct in the attic, which degrades from Renton’s damp attic humidity and can collapse or tear, causing pressure imbalances that make upstairs rooms stuffy. Sealant alone won’t fix a crushed or disconnected run; it needs physical repair or replacement. Typical duct repair in East Renton Highlands ranges from $280 for a localized boot reconnection to $1,200 or more for multiple run replacements in a difficult attic. We always inspect with a camera first, show you what we found, and write the price before we touch anything.
Crushed Flex Duct Recovery
On a 1984 two-story off the plateau’s east side, our tech ran a camera inspection and found a crushed run of original foil-tape-wrapped flex duct in the attic, its outer jacket torn from years of damp attic humidity. After a negative pressure setup and source removal with agitation tools, we sealed the torn jacket and reconnected the run, using Rotobrush equipment to verify airflow at the upstairs registers before we buttoned the attic back up. The homeowner’s front bedroom, stuffy for years, finally balanced out.
Galvanized Section Replacement
Homes from the 1970s often have original galvanized hard pipe that’s corroded at the seams. We cut out failed sections and splice in new ductwork, sealed with mastic and supported properly so it doesn’t sag or separate again.
Trusted Brands We Service in East Renton Highlands
Our equipment roster includes Rotobrush rotary brush systems for mechanical agitation, Nikro negative-air machines for controlled debris extraction, and filtration products from Honeywell, Aprilaire, Abatement Technologies, and Guardsman. We stock common repair parts for East Renton Highlands heat pump and electric forced-air configurations, which means faster turnaround on jobs that might otherwise wait for a parts run to Seattle. When we find a failed component during inspection, we can usually fix it same visit rather than rescheduling.
Common Duct Sealing Problems We See in East Renton Highlands Homes
- Damp attic humidity degrades original flex duct. The foil-tape-wrapped flex installed in 1980s plateau-east attices absorbs moisture over decades, the outer jacket delaminates, and the run collapses or tears. This isn’t a sealing job; it’s a repair, but it starts with the same inspection.
- Longer heating cycles reopen sealed joints. East Renton Highlands’ cooler microclimate means furnaces and heat pumps run more hours per day than in Renton proper. That sustained airflow pressure pushes through mastic that wasn’t applied thick enough or allowed to cure properly, especially on original galvanized seams.
- Heat pump blower profiles expose weak seals. Electric forced-air and heat pump systems common here run different air handler pressures than gas furnaces. A sealing job calibrated for gas equipment leaves gaps that show up as whistling, temperature imbalance, or excessive runtime on heat pump systems.
- Return air paths leak in crawl spaces. The 1970s ranches near May Creek often have return plenums in vented crawl spaces that pull in damp soil air and spores. Sealing these returns properly requires crawl access, proper PPE, and mastic rated for damp conditions, not hardware-store tape.
Pricing for Duct Sealing in East Renton Highlands, WA
A typical whole-system HVAC duct sealing in East Renton Highlands runs $450 – $850. Duct repair, when we need to replace crushed or torn runs, ranges from $280 for a single boot reconnection to $1,200 or more for multiple run replacements in a tight attic. What moves the price: accessibility (crawl space versus walk-up attic), extent of original material degradation, and whether your system is heat pump or gas furnace, which affects the sealing approach and register balancing time. We do not quote per-vent teaser prices that balloon once we’re inside. We inspect, we show you camera footage, we write one flat price per system, and that price does not move at the door. Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near East Renton Highlands
Our Duct Sealing in East Renton Highlands crews also work in Seattle, Spokane, Tacoma, and Vancouver. Each location operates under The Garrison Standard with independently owned teams, so the crew that knows your East Renton Highlands attic humidity and heat pump configurations is the crew that shows up.
Serving East Renton Highlands, WA - Our Local Coverage Area
We’re based in the East Renton Highlands 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 East Renton Highlands
The original foil-tape-wrapped flex duct in your attic has likely degraded from damp humidity and collapsed or torn, creating pressure imbalances that cleaning alone cannot fix. We camera-inspect the attic runs first, then repair or replace the damaged sections and seal the intact joints. Call (361) 326-5060 for a free inspection and written estimate.
Yes. Roughly 150 rainy days per year and longer heating cycles push more damp air through leaky joints, which loads and reopens seals faster than in drier suburbs. We use mastic rated for damp conditions and apply it thicker than the standard spec to account for this. Call (361) 326-5060 to assess your system’s current seal integrity.
We start with a static pressure test and camera inspection, then seal or repair based on your heat pump’s specific blower profile and MERV rating, not a generic gas-furnace assumption. We verify airflow at each register before we leave. Call (361) 326-5060 to schedule.
Minor jacket tears on structurally intact flex can sometimes be sealed and re-supported, but collapsed or extensively delaminated runs need replacement. We show you the camera footage and give you both options with written prices. Call (361) 326-5060 for an honest assessment.
We know the local housing stock: the 1970s galvanized, the 1980s foil-tape flex, the heat pump prevalence, and the damp attic conditions that degrade them. Our 365-Day Done Right Promise covers every repair in writing, and we arrive uniformed, background-checked, and on time. Call (361) 326-5060 to get it done by the book.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving East Renton Highlands and the greater Seattle area since 2004.