Fast, Reliable Duct Repair & Sealing Across Kenmore
Duct repair and sealing in Kenmore typically runs $280–$650 for most residential jobs, with same-day or next-day scheduling available when you call (877) 335-1974. We’re familiar with the specific challenges of Kenmore’s older housing stock — the 1950s-through-1980s ranch and split-level homes that dominate neighborhoods like Arrowhead, Inglewood, and the Sammamish River corridor. Our Duct Repair & Sealing team reaches Kenmore properties within 45 minutes from our Seattle base, and we carry the parts and materials needed for the flex-duct and sheet-metal systems common to this area.
Why Landmark Air Duct Cleaning Service Washington Is Kenmore’s Preferred Duct Repair & Sealing Company
We’ve built our reputation in Kenmore over 11 years by showing up with owner-led accountability on every job. Richard Anderson serves as both Owner and Lead Technician — he’s not dispatching crews he barely knows, he’s running the equipment and inspecting the work personally. That matters in Kenmore, where crawl-space duct repairs demand judgment calls about moisture damage that a rotating subcontractor might miss.
Our 732 verified reviews average 4.9 stars, and Kenmore homeowners specifically mention our thoroughness with older systems. We respond to Kenmore calls within the hour during business hours, and we know the local housing patterns: the crawl-space foundations along 68th Avenue NE, the post-war ranches near Saint Edward State Park, the split-levels in the Uplake area. This isn’t generic territory for us. We’ve pulled collapsed flex duct from too many Kenmore crawl spaces to treat this like any other suburb.
We use professional-grade Rotobrush and Nikro equipment — the same systems commercial restoration contractors rely on — and we stock mastic sealant, insulated flex duct, and rigid metal fittings sized for the older trunk-line configurations common in 98028 homes.
Our Duct Repair & Sealing Services in Kenmore
Duct Sealing
Air leaks in Kenmore ductwork waste 20–30% of conditioned air on average, but here the problem compounds faster. The persistent damp in crawl spaces near the Sammamish River degrades sealants prematurely, so we use mastic — a thick, brush-applied sealant that remains flexible and adheres to metal even with surface moisture — rather than foil tape that peels within seasons. We seal trunk-line seams, register boots, and plenum connections, then pressure-test to verify. Most Kenmore duct sealing jobs run $280–$450 for a single-system home.
Flex Duct Repair
This is the repair we perform most often in Kenmore. The bulk of local homes built between the late 1950s and 1980s run flex duct through unconditioned crawl spaces, and Kenmore’s damp microclimate destroys these lines from the outside in. On a recent job along the Sammamish River corridor, we found a 1970s ranch home where the flex-duct insulation jackets had wicked moisture and collapsed, compressing the inner liner and restricting airflow while harboring mold. Our crew removed the compromised flex duct, cleaned the metal trunk line, and replaced sections with new insulated flex duct sealed with mastic, restoring both indoor air quality and HVAC efficiency. Flex duct repair in Kenmore typically costs $180–$380 per run, depending on length and accessibility.
Metal Duct Repair
Older Kenmore homes with original galvanized sheet-metal ductwork face a different enemy: corrosion at seams and joints from decades of ground-moisture exposure. We patch small holes with metal sleeves and mastic, replace rusted sections with matching gauge metal, and re-seal the entire run. When corrosion is extensive — common in homes near the lake where fog lingers longest — we’ll advise whether repair or full replacement makes economic sense. Metal duct repair in Kenmore runs $320–$580 for typical partial-system work.
Duct Insulation
Replacing failed insulation on existing ductwork is critical in Kenmore’s climate. The low-lying bowl where Lake Washington meets the Sammamish River traps cold, foggy air through October-to-April; condensation forms on cold duct surfaces, and when insulation or vapor barriers fail, that condensation moves inside the ducts. We install new fiberglass wrap with intact vapor barriers, or upgrade to closed-cell foam insulation on exposed metal runs in particularly damp crawl spaces. Duct insulation work in Kenmore typically ranges $340–$620 depending on linear footage and crawl-space accessibility.
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 Kenmore
We maintain stock of repair materials sized for the systems installed in Kenmore’s housing stock: insulated flex duct, galvanized sheet metal, mastic sealant, and mechanical fasteners. For homeowners adding air quality protection after repair, we install Honeywell and Aprilaire whole-home filtration systems, plus UV sanitizing equipment from Abatement Technologies and Guardsman — brands we’ve selected for performance in Pacific Northwest moisture conditions. Parts availability means most Kenmore repairs complete in a single visit, not a return trip that leaves your system open another night.
Common Duct Repair & Sealing Problems We See in Kenmore Homes
- Flex-duct insulation jackets wick moisture and collapse. Kenmore’s persistently damp crawl spaces — especially along the Sammamish River corridor — saturate the fiberglass insulation surrounding flex duct. The jacket compresses, the inner liner kinks, and airflow drops by 30% or more while mold colonizes the trapped moisture. We find this dual problem far more frequently in Kenmore than in drier Bothell neighborhoods just east.
- Metal duct seams corrode from ground moisture. Original galvanized sheet metal in 1960s and 1970s Kenmore homes wasn’t designed for decades of humidity exposure. Seams rust through, leaking conditioned air into crawl spaces and pulling musty air back into supply lines. The corrosion often hides above the visible run, requiring full inspection with borescope cameras.
- Original duct tape fails in humid conditions. The gray cloth-backed tape used on original installations dries and separates within 10–15 years in normal climates; in Kenmore’s damp crawl spaces, it often fails faster. Gaps open at joints, leakage spikes, and the tape residue complicates proper re-sealing with mastic.
- Vapor-barrier failures compound condensation. Many Kenmore crawl spaces have compromised or missing ground vapor barriers — common in homes built before modern building codes. Moisture rises through soil, hits cold ductwork, and overwhelms any marginal insulation. Repair without addressing the vapor barrier often fails within seasons.
Pricing for Duct Repair & Sealing in Kenmore, WA
| Service | Typical Range in Kenmore |
|---|---|
| Duct sealing (single system, mastic) | $280–$450 |
| Flex duct repair/replacement (per run) | $180–$380 |
| Metal duct repair (partial system) | $320–$580 |
| Duct insulation replacement | $340–$620 |
| Full system inspection with report | $150–$220 |
What moves a Kenmore job toward the higher end: crawl spaces with standing water or limited access requiring protective gear, extensive mold remediation before repair can begin, or homes with multiple HVAC zones and complex trunk-line configurations. What keeps costs down: catching flex-duct collapse early before it damages the connected metal trunk, or scheduling sealing before corrosion requires metal replacement. We provide free written estimates before any work begins — call (877) 335-1974 to schedule.
We Also Serve Cities Near Kenmore
Our service radius covers the full north Lake Washington area. We regularly perform duct repair and sealing in Lake Forest Park — where similar mid-century homes face comparable moisture issues — and across Bothell, Bothell East, and Bothell West, where the elevation rise and distance from the Sammamish River generally mean drier crawl spaces and different failure patterns. The same owner-led team and equipment serve all five communities.
Serving Kenmore, WA — Our Local Coverage Area
We’re based in the Kenmore 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 — Duct Repair & Sealing in Kenmore
Kenmore’s position at the confluence of the Sammamish River and Lake Washington creates a persistently damp microclimate that causes moisture wicking and collapse of flex-duct insulation jackets in crawl spaces, a problem rarely seen in drier nearby suburbs like Bothell. The ground moisture here is measurably higher, and vapor-barrier failures are more common in the area’s older housing stock. If your flex duct feels soft or sagging, call (877) 335-1974 — estimates are free.
You’ll notice weak airflow from registers, musty odors when the HVAC runs, visible sagging or flattening of flex duct in the crawl space, or unexplained spikes in energy bills. In Kenmore’s climate, these symptoms often appear together rather than gradually. Call (877) 335-1974 for an inspection — catching this early prevents mold spread into the trunk line.
Duct sealing with mastic resolves air leaks in structurally sound metal ductwork, but if corrosion has thinned the metal or created holes larger than a quarter, section replacement is necessary. We inspect with borescope cameras to make this determination before recommending repair scope. For a clear assessment of your metal ducts, call (877) 335-1974 — we’ll show you what the camera sees.
Kenmore’s high crawl-space humidity accelerates the drying and separation of cloth-backed duct tape by 30–50% compared to drier inland climates; we routinely find original tape failing within 8–12 years here versus 15+ elsewhere. We remove all failed tape residue and re-seal with mastic, which remains flexible and bonded under moisture exposure. Schedule removal and proper re-sealing at (877) 335-1974.
Yes — in fact, Kenmore’s typical failure mode creates both problems simultaneously. Collapsed flex duct restricts airflow (energy loss) while trapped moisture breeds mold (IAQ hazard). Our repairs remove contaminated materials, clean accessible trunk lines with Rotobrush equipment, install new insulated duct, and seal with mastic to prevent recurrence. Call (877) 335-1974 to discuss whether repair or full replacement better serves your system.
Written by Richard Anderson, Owner and Lead Technician at Landmark Air Duct Cleaning, serving Kenmore and the greater Seattle area since 2013.