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 Lansdowne
We seal ducts in Lansdowne’s Victorian and Colonial homes where gravity-duct systems from the 1920s meet forced-air retrofits from the 1970s, and where coal-era chutes still open into live duct runs. Our Duct Sealing in Lansdowne crews dispatch from our Philadelphia office and carry the mastic, metal tape, and negative-air test gear to handle plaster-wall chases, attic retrofit runs, and shared building systems that newer suburbs never see. Call (361) 326-5060 for a free estimate. We’ll show up in the window we promised, price the job in writing before we touch anything, and back it with our 365-Day Done Right Promise.
Why Hollis Air Duct Cleaning Is Lansdowne’s Preferred Duct Sealing Company
Hollis Air Duct Cleaning has been part of the Garrison Partners family since 2004, and our Duct Sealing team knows Lansdowne’s housing stock inside and out. We’ve worked on Tudor Revivals near Lansdowne Avenue, Colonials along Baltimore Pike, and converted multi-units in the walkable core where parking is tight and access means coordinating with neighbors.
Our technicians are background-checked, uniformed, and expected to operate by The Garrison Code: arrive inside the quoted window, price in writing, complete the job by the book, leave the site clean. Every repair carries our 365-Day Done Right Promise in writing. If the seal 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 callback queues. No waiting until Monday for a scheduling answer.
Duct Repair in Lansdowne
Duct Repair in Lansdowne means fixing the partially disconnected runs, corroded metal joints, and abandoned coal-era stubs that leak conditioned air into wall cavities and basements. In a borough where most homes were built before 1940, duct repair is less about replacing new flex-duct and more about reconnecting what previous owners patched over. A typical duct repair in Lansdowne runs $280 – $520 depending on access and the extent of the disconnection.
Reconnecting Hidden Runs Behind Plaster
We camera-inspect before we cut. In Lansdowne’s plaster-wall homes, a disconnected segment can sit behind horsehair insulation for decades, blowing dust every time the blower cycles. We locate the break, open the smallest necessary access, reconnect the run with proper mechanical fasteners, and seal with mastic rated for the temperature swing of your attic or basement.
Sealing Abandoned Coal Chute Connections
The old coal chute in your Lansdowne basement may still tie into the live duct system. We find these openings with a smoke pencil or camera, then seal them permanently with mastic and reinforced metal tape. Leaving them open means your system pulls basement air, radon, and dust every time it runs.
Air Duct Sealing in Lansdowne
Our Lansdowne Duct Sealing addresses the gaps, seams, and chases that let heated or cooled air escape into walls, attics, and between floors. In older homes with retrofit ductwork, sealing can improve airflow at the registers by 20 – 30 percent and reduce the dust that plaster-wall chases pull back into the system. A typical whole-system duct sealing job in Lansdowne runs $480 – $890 for a single-family home, with multi-unit buildings priced per system after inspection.
Negative-Pressure Testing After Sealing
We don’t guess. After sealing, we test the system under negative pressure to verify the fix. Our Nikro negative-air machines measure leakage at the duct seams and register boots. If the numbers don’t meet our standard, we reopen the access and reseal. The homeowner sees the before and after.
Mastic vs. Tape in Old Metal Ducts
Duct tape fails. On Lansdowne’s original metal ductwork, we use water-based duct sealing mastic, brushed into every joint and seam, reinforced with mesh on larger gaps. Mastic remains flexible through decades of thermal expansion. It is the standard for duct sealing in old housing stock, and it is what we apply on every job.
Trusted Brands We Service in Lansdowne
We carry filtration and sealing products from Aprilaire, Abatement Technologies, and Guardsman on our Lansdowne trucks, along with professional-grade mastic and metal tapes. Our equipment roster includes Rotobrush rotary brush systems for pre-sealing cleaning and Nikro negative-air machines for post-seal verification. If your Lansdowne home has an Aprilaire media air cleaner or a Guardsman UV system, we inspect the duct connections to those units as part of our sealing scope. Parts are stocked for common configurations, so we’re not ordering mid-job and making you wait.
Common Duct Sealing Problems We See in Lansdowne Homes
- Sealant bridging gaps in plaster-wall chases without fixing the disconnect behind. A previous contractor ran tape and mastic over the wall surface, but the duct segment inside was partially separated. The leak continued, hidden, until we camera-inspected and reconnected the run properly.
- Attic and basement retrofit runs sealed only at accessible joints. The buried connections inside horsehair-insulated chases get skipped because they’re hard to reach. We use flexible camera gear and targeted access cuts to reach those segments, seal them, and repair the plaster.
- Shared dryer-vent stacks sealed at the unit side while the common vertical run stays open. In Lansdowne’s converted multi-units, lint keeps accumulating in the shared stack. We coordinate with building owners to inspect and clean the full vertical run before sealing any unit connections.
- Coal chute openings still tied to live ductwork. Technicians sealing ducts here routinely find the old coal chute or abandoned basement duct stub still connected to the modern system. It’s an unsealed, dust-belching opening that no new-construction suburb would have. We find it, seal it, and test to confirm.
Pricing for Duct Sealing in Lansdowne, PA
A typical duct sealing job in Lansdowne runs $480 – $890 for a single-family home with accessible basement or attic duct runs. Homes with extensive plaster-wall chases, multiple disconnected segments, or shared building systems fall toward the higher end. Multi-unit buildings are priced per system after inspection, usually $320 – $580 per unit for the duct sealing scope.
What moves the price: access difficulty (crawl space vs. full basement), number of disconnected runs found during camera inspection, whether the old coal chute needs sealing, and whether we coordinate with neighbors for shared-stack buildings. We do not quote per-vent teaser prices. We inspect, write the full price, and get your approval before any work starts. Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Lansdowne
Our crews work throughout Delaware County and the first-ring Philadelphia suburbs. We regularly seal ducts in Darby, Clifton Heights, Drexel Hill, and Sharon Hill, where the housing stock and coal-era duct conditions are similar to what we find in Lansdowne. Same standards, same written pricing, same 365-Day Done Right Promise.
Serving Lansdowne, PA - Our Local Coverage Area
We’re based in the Lansdowne 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 Lansdowne
Yes. The coal chute is often still connected to the live duct system, creating an unsealed opening that pulls basement air and dust into your airflow. We locate the connection with a smoke pencil or camera, seal it permanently with mastic and reinforced metal tape, and test under negative pressure to confirm the fix. Call (361) 326-5060 to schedule an inspection.
Yes. We coordinate parking and equipment staging with you in advance. Our vans carry portable negative-air gear and compact camera systems that don’t require a full driveway setup. We also schedule with building neighbors when shared systems need inspection. Call (361) 326-5060 to discuss access for your specific street.
Sealing your unit’s duct connection won’t fix lint accumulation in the shared vertical stack, which is why we also offer our Dryer Vent Cleaning in Lansdowne. We inspect and clean the full common run first, then seal your unit’s connection properly. Without cleaning the stack, the seal does nothing for the lint pathway. Call (361) 326-5060 for a building-wide assessment.
We camera-inspect to locate the disconnect, then make the smallest necessary access cut in the plaster, repair the duct, seal with mastic, and patch the wall. We don’t tear out full wall sections. The plaster repair is part of our scope, and we leave the site clean. Call (361) 326-5060 for a camera inspection.
Mid-renovation is the ideal time. With walls open and chases exposed, we can reach and seal every segment that would be inaccessible later. Sealing before you close up the walls saves the cost of re-opening plaster later. We coordinate with your contractor’s schedule. Call (361) 326-5060 to time the work with your renovation.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Lansdowne since 2004.