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 Severna Park
Duct sealing in Severna Park typically runs $800 – $2,400 for a whole-home job, depending on whether we’re sealing accessible joints in a 1990s colonial or replacing failed insulation on original 1950s metal trunks in a river-community rancher. Our crews dispatch from our Baltimore office and cover all of Severna Park, from Olde Severna Park to Shipleys Choice, with appointments usually available within a few business days. Call (361) 326-5060 for a free written estimate.
We’ve worked in Severna Park long enough to know the difference between a tight flex-duct attic system off Ritchie Highway and a crawlspace metal trunk in Round Bay that’s been breathing Severn River humidity since 1962. That local knowledge changes what we bring to the job, what we charge, and what we promise will actually hold up.
Why Hollis Air Duct Cleaning Is Severna Park’s Preferred Duct Sealing Company
Our reputation in Severna Park was built on showing up inside the window and leaving with the site clean. We’re part of the Garrison Partners family, independently owned and operated under The Garrison Standard since 2004. That standard means written prices before any work starts, background-checked and uniformed technicians, and a 365-Day Done Right Promise on every job. If the seal fails within a year, we come back at no charge, including a free second visit.
Dispatch and scheduling for Severna Park are coordinated from our Baltimore office, but the crews that arrive at your door live and work in this market. They know which neighborhoods sit on fill near the water, which basements flood in a spring tide, and why a fogging “sanitiser” upsell won’t fix a duct that’s condensing river air inside the run. Calls are answered by a live person 24 hours a day, 7 days a week. No voicemail loops, no callback queues.
Duct Sealing Services in Severna Park
Duct Sealing Services in Severna Park cover everything from sealing accessible joints and registers with mastic and metal-backed tape to replacing failed external insulation on original metal trunks that have been condensing humidity for decades. A typical sealing job in Severna Park runs $800 – $1,800 for standard joint sealing in newer homes, and $1,400 – $2,400 when we’re removing water-damaged insulation and sealing corroded seams in river-community crawlspaces. We use professional-grade equipment from Nikro and Abatement Technologies, and every job starts with a written price that doesn’t move once we’re inside.
Joint and Seam Sealing
We seal supply and return joints with duct mastic, a thick, flexible compound that bonds to metal and flex duct better than tape alone. In Severna Park’s 1980s-90s colonials with flex duct in attics, we pay special attention to where flex meets metal plenums. Those connections loosen over time, especially under the thermal stress of Maryland’s humid summers and cold snaps.
Insulation Replacement and Sealing
In Round Bay, Olde Severna Park, and Manhattan Beach, we routinely find original 1950s-60s rectangular metal trunks with torn external insulation. Sealing here means removing the saturated wrap, treating the metal for mildew, replacing the insulation with new vapor-barrier wrap, and sealing every longitudinal seam and branch joint. It’s more than joint sealing. It’s stopping the moisture pathway that caused the damage.
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.
Duct Insulation in Severna Park
Duct Insulation in Severna Park is often the missing half of a sealing job in the older river communities. A typical insulation replacement on a crawlspace or basement trunk runs $600 – $1,400, depending on linear footage and accessibility. In Severna Park’s postwar waterfront neighborhoods, we see more insulation failure than inland Anne Arundel County because the humid Severn River air accelerates condensation on any gap or tear in the vapor barrier.
Vapor-Barrier Insulation for Crawlspace Systems
We install foil-faced fiberglass or closed-cell foam insulation with a sealed vapor barrier on the exterior. In Severna Park crawlspaces, especially those below the water table in spring, this barrier is what keeps humid outside air from reaching the cold metal duct and condensing. Without it, even a perfectly sealed joint will weep moisture.
Attic Flex-Duct Insulation Upgrades
Newer Severna Park homes with flex duct in attics rarely need full insulation replacement, but we do see compression damage from storage or rodent activity. Our techs inspect for flattened runs that restrict airflow and cause the blower motor to overwork. We replace damaged sections and seal all connections before the new insulation goes in.
Trusted Brands We Service in Severna Park
Our equipment roster includes Nikro negative-air machines and Abatement Technologies HEPA filtration systems, the same tools commercial crews use in hospitals and schools. For filtration upgrades tied to sealing jobs, we stock Honeywell and Aprilaire media filters locally, so Severna Park customers aren’t waiting on shipped parts. We also carry Guardsman antimicrobial coatings where appropriate, applied only after source removal and moisture correction, never as a substitute for them. Fast turnaround matters in this humidity. A duct left open in July is a duct growing mildew by August.
Common Duct Sealing Problems We See in Severna Park Homes
- Torn insulation on original metal trunks near the Severn River. In Round Bay and Olde Severna Park, the external wrap on 1950s-60s rectangular metal ducts cracks and pulls away. Humid river air hits cold metal, condenses inside the run, and creates standing water or black mildew. Sealing over this without replacing the insulation traps the moisture and guarantees the mildew returns.
- Damp air handlers in crawlspaces and basements. We see this in Manhattan Beach and near-water lots throughout Severna Park. The equipment itself sits in humid air, becoming a continuous moisture source. Sealing ducts without addressing the air handler enclosure or adding a dehumidification strategy is a temporary fix at best.
- Fogging “sanitiser” upsells sold as duct sealing. Some outfits spray a chemical fog and call the job done. In Severna Park’s river communities, the mildew is fed by ongoing condensation from failed insulation and humid air infiltration. Fogging doesn’t stop the moisture pathway. We see the same black mildew back within a season.
- Skipped camera inspections on original metal runs. A register can look clean while three feet inside the trunk there’s standing water and corrosion. We run camera inspections on every Severna Park job involving original metal ductwork. Sealing corroded, water-logged metal from the outside fails from the inside within months.
Pricing for Duct Sealing in Severna Park, MD
Whole-home duct sealing in Severna Park typically runs $800 – $2,400. Standard joint sealing in a 1980s-1990s colonial with accessible flex duct falls at the lower end, around $800 – $1,400. Original metal trunk work in river-community crawlspaces, with insulation removal, mildew treatment, and re-wrapping, runs $1,400 – $2,400. We price by the system, not by the vent. One flat price per system, agreed in writing before we touch anything.
What moves the number: accessibility (crawlspace vs. finished basement), linear footage of damaged insulation, whether we need to replace sections of metal duct, and whether the air handler enclosure itself needs sealing. Every estimate is free. We inspect, photograph what we find, and hand you a written price. No per-vent add-ons, no “we found another problem” surprises at the door.
Call (361) 326-5060 for an exact quote on your Severna Park home. Estimates are free.
We Also Serve Cities Near Severna Park
Our crews regularly work in Severna Park and the surrounding communities: Crownsville, Arnold, Pasadena, and Glen Burnie. Each shares Anne Arundel County’s humid climate but has its own housing stock and duct configurations. Our Duct Sealing team brings the same written-price, written-guarantee standard to every job, whether it’s a waterfront rancher in Round Bay or a colonial in Crownsville.
Serving Severna Park, MD - Our Local Coverage Area
We’re based in the Severna Park 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 Severna Park
The tidal Severn River and Chesapeake Bay create persistently high humidity that inland Anne Arundel County doesn’t match. In river communities like Round Bay, Olde Severna Park, and Manhattan Beach, that humid air infiltrates through torn duct insulation, condenses on cold metal, and accelerates corrosion, mildew, and joint failure. Homes even a few miles inland, off Ritchie Highway in Shipleys Choice or Chartwell, typically see slower insulation degradation because the ambient humidity is lower and less constant. Call (361) 326-5060 for an inspection if you’re in a waterfront neighborhood and haven’t had your ducts checked in five years.
Duct sealing closes the physical pathways where unconditioned air enters the system, replacing failed insulation and sealing joints with mastic and proper tape. A fogging treatment sprays antimicrobial chemical into the duct without closing those pathways. In Severna Park’s humid river communities, the moisture keeps coming back through the same gaps, so the mildew returns within a season regardless of what was fogged. We perform source removal under negative pressure with HEPA filtration, correct the moisture pathway, then seal. Call (361) 326-5060 for a free estimate on actual sealing work.
We run a camera inspection on every original metal duct system in Severna Park’s older neighborhoods. The register can look clean while three feet inside the trunk there’s standing water, black mildew, or corrosion pitting the metal. Our techs also check external insulation for tears, gaps, or water staining, and measure humidity at the air handler. We show you the camera footage before we quote. Call (361) 326-5060 to schedule an inspection.
Yes, but the approach is different. Flex duct in attics typically fails at the connections to metal plenums and at points where it’s been compressed by storage or foot traffic. We seal those connections, replace damaged flex sections, and verify that attic insulation hasn’t pulled away from the duct runs. Shipleys Choice homes don’t usually have the river-humidity condensation issues of Round Bay, but they do have thermal stress from hot attics and cold winter snaps that loosen connections over time. Call (361) 326-5060 for an attic duct inspection.
Proper duct sealing removes the moisture source, removes the existing contamination, and then closes the pathways. In Severna Park river communities, that means replacing torn external insulation so humid air can’t reach cold metal, sealing joints with mastic so there’s no air infiltration, and running the system under negative pressure with HEPA filtration to extract existing mildew and debris. We don’t seal over wet metal. We dry it, treat it, insulate it, and then seal it. Post-job static pressure tests confirm the blower motor isn’t overworking to push air through leaks. Call (361) 326-5060 for a free written estimate.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Severna Park since 2004.