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 Woodinville
Duct sealing in Woodinville typically runs $450 – $1,200 for a whole-home seal, depending on how many branch runs need repair and whether we find crushed or disconnected ducts behind finished walls. Most jobs take a half day, and we price them in writing before any work starts. Call (361) 326-5060 for a free estimate.
We’ve worked in Woodinville long enough to know the patterns. The 1980s subdivisions near Leota and the newer custom builds out by the wineries don’t have the same problems, and they don’t get the same fixes. Our crews dispatch from the Seattle office and carry the parts and mastic to handle both: the degraded flex duct at the plenum in older homes, and the crushed branch runs behind bonus-room walls in the 2000s builds. Roy Castellanos built Hollis Air Duct Cleaning on The Garrison Standard, which means we show up inside the window, write the price down, and leave the site clean. That standard applies whether we’re sealing a three-bedroom rambler off Woodinville-Duvall Road or a multi-zone system in a wine-country estate.
Why Hollis Air Duct Cleaning Is Woodinville’s Preferred Duct Sealing Company
Woodinville homeowners call us back because we treat duct sealing as a repair trade, not a sales pitch. Our Duct Sealing team arrives in uniform, background-checked, with the tools to do the job by the book: Rotobrush rotary systems for agitation, Nikro negative-air machines for containment, and professional-grade mastic for seals that hold.
We answer our phones live, 24 hours a day. No voicemail loops, no callback queues. Scheduling runs through the Seattle office, and crews serve Woodinville locally with the parts to finish most jobs in one visit. The 365-Day Done Right Promise covers every seal we make: if it fails within a year, we return and make it right at no charge, including a free second visit. That’s written on every job, not implied.
Our techs know the local housing stock. They’ve found crushed flex runs behind finished walls in homes near the Sammamish River valley and replaced degraded plenum connections in subdivisions off NE 175th Street. That local knowledge means faster diagnosis and no guesswork on what parts to bring.
Duct Repair in Woodinville
Duct Repair in Woodinville is often the real fix hiding behind a cleaning call. We open the system and find disconnected branches, crushed flex runs, or joints that have pulled apart at the air handler. In Woodinville’s 1980s – 1990s subdivisions, original flex duct degrades at the plenum collar and at every joint, leaking conditioned air into the crawlspace or attic. In the 2000s – 2010s custom homes near the wine country, we see bonus-room runs over garages that were kinked during construction and have been leaking for fifteen years. A typical duct repair in Woodinville runs $280 – $650 per branch run, with whole-system repairs ranging $650 – $1,400 depending on access and material.
Crushed Runs Behind Finished Walls
This is the one that frustrates homeowners. The room never heats right, so they blame the furnace. Our camera inspection often shows a flex duct crushed behind drywall, sometimes from a framing nail, sometimes from the original installer forcing a too-tight bend. We cut strategic access, replace the damaged section, and seal with mastic and mesh. The room comes back online.
Degraded Plenum and Collar Connections
The connection between your air handler and the main trunk is a pressure point. In Woodinville’s older homes, the original tape has dried and failed, or the flex duct has pulled away from the collar. We reseat the connection, secure it with mechanical fasteners, and seal with mastic rated for the temperature swing. No duct tape. Duct tape fails on ducts.
Air Duct Sealing in Woodinville
Air Duct Sealing in Woodinville is about pressure integrity. A duct system is a closed loop: supply pushes conditioned air out, return pulls it back. Every leak is a breach in that loop. Supply leaks waste money by heating your crawlspace. Return leaks pull unfiltered air, pollen, and whatever lives in your attic straight into the blower and back through your vents. In Woodinville, where spring pollen counts spike and wildfire smoke drifts over the Cascades, return-side leaks are a real air-quality problem. Whole-home air duct sealing in Woodinville typically runs $450 – $1,200, with spot sealing of individual branch runs at $180 – $340.
Mastic Sealing at Joints and Seams
We brush on water-based duct mastic at every joint, seam, and penetration. It cures to a flexible seal that handles thermal expansion better than tape. For high-pressure joints at the plenum, we embed fiberglass mesh in the mastic for structural reinforcement. This is standard practice, not an upgrade.
Sealing Fresh-Air Intake Collars
Woodinville’s newer homes often have fresh-air intakes for code compliance, sometimes located near gravel driveways or vineyard access roads. Without a tight seal at the intake collar, those intakes pull pollen and fine dust straight past the filter. We seal the collar and verify with a pressure test that the intake is drawing from outside, not leaking from the attic.
Trusted Brands We Service in Woodinville
We stock parts and filtration products from Honeywell, Aprilaire, and Guardsman, and we carry the sealants and mastic to match. Our equipment roster includes Rotobrush rotary brush systems for mechanical agitation inside the ductwork and Nikro negative-air machines for containment during the job. For Woodinville customers, that means we don’t order parts after we arrive. We diagnose, price, and execute in the same visit for most standard repairs. When a custom home’s multi-zone system needs a specific damper or collar size, we source it fast through our Seattle-based supply chain. No waiting, no return trips for a part we should have had.
Common Duct Sealing Problems We See in Woodinville Homes
- Disconnected or crushed duct runs behind bonus-room walls. Woodinville’s 2000s custom builds often have bonus rooms over garages with long flex runs that were kinked during construction. The room never reaches temperature, and the homeowner has been overworking the furnace for years.
- Fresh-air intakes pulling pollen and road dust. Intakes near gravel driveways and vineyard access roads draw spring pollen and fine dust directly into the return side. Without sealing at the collar, that debris bypasses the filter and coats the blower motor and evaporator coil.
- Degraded flex duct at the plenum in 1980s – 1990s subdivisions. Original installations near Leota and Woodinville-Duvall Road used tape and friction fits that fail after twenty-plus years of thermal cycling. The joints leak, pressure drops, and the system pulls crawlspace or attic air through unsealed seams.
- Multi-zone systems with unbalanced pressure. Large custom homes with complex HVAC zoning often have dampers and branch runs that were never properly sealed at commissioning. One zone overpressurizes, another starves, and the homeowner pays to condition air that never reaches the rooms.
Pricing for Duct Sealing in Woodinville, WA
Here’s what duct sealing costs in Woodinville’s market:
| Service | Typical Range |
|---|---|
| Spot sealing (single branch run) | $180 – $340 |
| Whole-home duct sealing | $450 – $1,200 |
| Duct repair per branch run | $280 – $650 |
| Whole-system repair and seal | $650 – $1,400 |
What moves the price: access (finished walls vs. open crawlspace), number of branch runs, whether we find crushed or disconnected duct that needs replacement versus simple sealing, and the condition of the original plenum connection. We inspect first, price in writing, and the number doesn’t move at the door. Every estimate is free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Woodinville
Our crews work throughout the Eastside. We regularly handle Duct Sealing in Woodinville and travel to Bothell, Kenmore, Redmond, and Kirkland for multi-zone systems and whole-home sealing jobs. The same written pricing, the same 365-Day Done Right Promise, the same uniformed technicians at every stop.
Serving Woodinville, WA - Our Local Coverage Area
We’re based in the Woodinville 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 Woodinville
A bonus room over the garage that never reaches temperature usually has a crushed or disconnected duct run behind the finished wall. Cleaning the duct doesn’t fix a physical obstruction. We camera-inspect the run, cut strategic access if needed, and repair or replace the damaged section. Call (361) 326-5060 and we’ll diagnose it properly.
Yes, especially on the return side. Return duct leaks pull unfiltered air from your attic or crawlspace, and in Woodinville, that air carries spring pollen and summer wildfire smoke particulates. Sealing those leaks forces all intake through your filter, which is designed to catch those particles. For homes with fresh-air intakes near driveways or vineyards, we also seal the intake collar to prevent bypass.
We find degraded flex duct at the plenum and joints, tape that has dried and failed, and supply or return leaks that have been pulling unconditioned air for decades. The debris is usually household dust and pollen, not urban grime. The real fix is often sealing or replacing the failed connections, not just vacuuming the line.
NADCA standards require mechanical agitation (we use Rotobrush rotary systems) combined with negative-air containment (Nikro equipment) before any sealant application. The duct surface must be clean for mastic to bond properly. We follow this sequence on every job, which is why our seals hold and why we can back them with the 365-Day Done Right Promise.
It can, if the high bills come from duct leakage rather than equipment inefficiency. Multi-zone systems depend on pressure balance; unsealed branch runs or leaking dampers force the blower to work harder and longer. We pressure-test the system, identify the leaks, and seal them. If the equipment itself is the problem, we’ll tell you that too. Call (361) 326-5060 for an honest assessment.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Woodinville and the greater Seattle area since 2004.