Whole-home duct cleaning
Dryer vent cleaning
Camera inspection
Sanitizing & deodorizingWhole-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.
Fast, Reliable Duct Sealing Across Port Washington
Duct sealing in Port Washington typically runs $450 – $1,100 per system depending on the number of registers and how many leaks need mastic work, and most jobs on the peninsula are completed in a single visit. If your heating and cooling bills climb every summer while certain rooms stay stuffy no matter what, you’re likely losing conditioned air through failing duct seams. That’s a fixable problem, and it’s one our crew handles in Port Washington every week, from the older colonials near Main Street to the larger waterfront properties along Manhasset Bay. Call (516) 559-4917 and we’ll give you a written price before any work starts.

Why Hollis Air Duct Hempstead Is Port Washington’s Preferred Duct Sealing Company
Homeowners in Port Washington call us because we show up inside the quoted window, write the price down before touching a single seam, and stand behind the seal for a full year under our 365-Day Done Right Promise. Roy Castellanos leads our team, and the standard he sets is simple: if the work fails within a year, we come back at no charge. That includes a free second visit. No argument, no negotiation, just the fix.
Our technicians are background-checked and uniformed, so you know exactly who’s walking into your home. We run professional-grade equipment from Rotobrush and Abatement Technologies, not a hardware-store flashlight and a prayer. And when you call, a live person answers anytime, day or night. No voicemail loops, no “we’ll get back to you on Monday.”
We don’t chase the cheapest bid in Port Washington. We compete on discipline: arrive when we said, price it in writing, do the work by the book, and leave the site clean. That’s The Garrison Standard, and it applies to every job we run on the peninsula.
Styles & brands we work with




Duct Sealing Services in Port Washington
Duct Sealing Services in Port Washington address the leaks and failing seams that quietly bleed conditioned air into attics, crawlspaces, and wall cavities. A home near Manhasset Bay deals with salt-laden air that corrodes galvanized duct seams over time, while inland homes near Beacon Hill contend with pollen and dust pushing through every gap. Either way, the fix is the same discipline: locate every leak, seal it with mastic and foil tape, and document the pressure change so you can see the result.
Mastic Sealing and Camera Inspection
We don’t guess where a duct is leaking. We run a camera through the supply and return lines first, map every gap and pinhole, then apply mastic and foil tape to each seam. On older Port Washington homes with retrofitted systems, this matters because the original ductwork was often pieced together decades ago with undersized runs that leak at every joint.
Expect us to test at registers, boots, and plenum connections. A sealed duct that still leaks at a far-end boot leaves the blower motor overworking, and we don’t call that done.

Negative Pressure Setup and Testing
Before we seal, we run a negative-air setup from Abatement Technologies to pull contaminants away from the work area. After the mastic cures, we take static pressure readings and compare them to the original baseline. That before-and-after documentation is yours to keep, because work you can’t see deserves proof you can read.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Duct Insulation in Port Washington
Duct Insulation in Port Washington is about keeping the air you paid to heat or cool at the right temperature until it reaches the register. Runs through unheated attics and crawlspaces lose energy fast, especially in older homes where insulation was never added or has since broken down. We wrap ducts with insulation rated for coastal humidity, which matters near Hempstead Harbor where fiberglass that absorbs moisture loses its effectiveness and invites mold.
Attic and Crawlspace Runs
Long runs through unfinished attics are the worst offenders in Port Washington. In winter, heated air cools off before it reaches the far bedrooms; in summer, the opposite happens. We inspect every accessible run, note where insulation is missing or compressed, and replace it with material that holds up to the peninsula’s humidity.
Moisture-Resistant Wrapping for Coastal Homes
Homes within a half-mile of the water need different insulation than inland properties. Salt spray and high humidity break down standard fiberglass faster. We use moisture-resistant wrapping designed for exactly this environment, and we document the R-value on every line item in your written estimate.

Trusted Brands We Service in Port Washington
We service and seal ductwork tied to equipment from Aprilaire, Rotobrush, and Guardsman, and we stock common sealant, mastic, and insulation materials locally for Port Washington jobs. That means faster turnaround when you call from Manhasset Isle or Flower Hill. If your system includes filtration from Aprilaire or Guardsman, we’ll verify the filter housing is sealed correctly too, because a good filter does nothing if air bypasses it through an unsealed gap.
Common Duct Sealing Problems We See in Port Washington Homes
- Salt corrosion on waterfront properties near Manhasset Bay and Hempstead Harbor. Galvanized duct seams develop pinholes as salt-laden air eats at the metal. You’ll see a chalky white residue inside return ducts and a persistent musty smell even after cleaning.
- Improvised retrofit ductwork in 1920s – 1960s homes. Many older Port Washington houses had central air added decades after construction, with undersized runs and improvised connections that leak at every joint. Sealing one section without addressing airflow imbalances means failure within a year.
- Leaking far-end boots on large estate properties. Long duct runs through attics and crawls in bigger homes often leak at the boot where the duct meets the register. Homeowners notice weak airflow in the farthest rooms, and a blower motor that never stops running.
- Pollen and debris infiltration in inland neighborhoods like Beacon Hill. Mature tree canopies drop pollen, seed pods, and fine debris that work into every unsealed gap. Sealing the visible duct sections while leaving hidden leaks means the problem returns by the next pollen season.
See the difference
Before
After
Before
After
Before
AfterPricing for Duct Sealing in Port Washington, NY
A typical single-system duct sealing job in Port Washington runs $450 – $850, while larger homes with two or three separate systems land between $850 and $1,100. Homes near the water often run toward the higher end because corrosion at seams requires more prep work and mastic application. The price you’re quoted is the price you pay: one flat number per system, written down before we start, with no per-vent add-ons and no surprise at the door. Call (516) 559-4917 for a free estimate, and we’ll send a technician who can walk your ductwork and give you a number that day.
We Also Serve Cities Near Port Washington
Our Duct Sealing team runs jobs throughout the peninsula and nearby Nassau County communities, including Flushing, Westbury, Hempstead, and Syosset. If you’re just outside Port Washington proper, call and ask. Chances are we’re already working a few blocks from you.
Serving Port Washington, NY - Our Local Coverage Area
We’re based in the Port Washington 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 Port Washington
Homes near Manhasset Bay or Hempstead Harbor need duct sealing that addresses salt-driven corrosion at galvanized seams, not just gaps at visible joints. Salt-laden air eats pinholes in metal over time, and those leaks pull in humid, unconditioned air even when visible duct sections look fine. We inspect for corrosion first, prepare the metal surface before applying mastic, and use moisture-resistant materials that hold up to the coastal environment. Call (516) 559-4917 for an inspection if you’re within a half-mile of the water.
You can seal just the system that’s leaking, and our pricing is always per system, not per home. A single system in a 1950s Port Washington colonial typically runs $450 – $850, while sealing all three systems in a larger home lands between $850 and $1,100 total. We’ll inspect each system separately, tell you which one is losing air, and give you a written price for exactly what needs doing. No bundle, no pressure, just the numbers.
You should receive before-and-after static pressure readings, a camera inspection summary showing the leaks we found and sealed, and a written list of every material used and where. We document the pressure differential at registers and boots before and after sealing so you can see the change in airflow, not just take our word for it. NADCA-style documentation for work you can’t see is the standard, not an add-on. If a crew won’t provide it, don’t hire them.
Return ducts in Beacon Hill and Manorhaven often accumulate a chalky white residue from salt and humidity interaction, and you can’t seal properly over that surface. The residue prevents mastic from bonding, and the underlying corrosion keeps worsening underneath. We clean and prepare the metal before applying any sealant, so the fix actually holds instead of peeling off within months.
Yes. Sealing the gaps that let pollen and fine debris into your ductwork means less of it reaching your living space and less of it recirculating through the system. Inland Port Washington homes under mature tree canopies deal with a steady supply of pollen, seed pods, and fine dust pushing into every unsealed seam. We map and seal those infiltration points, then document the pressure change so you know the seal is holding. Call (516) 559-4917 for a free estimate on your system.
Why Coastal Sealing Knowledge Matters in Port Washington
Port Washington’s coastal-inland split means homes near Manhasset Bay and Hempstead Harbor need duct sealing that specifically addresses salt-driven corrosion at seams, while inland homes more often need sealing to block pollen and debris infiltration from mature tree canopies. A generic duct sealing company from a neighboring town might treat every home the same way, but the peninsula doesn’t work that way. The failure mode is different depending on whether you’re a quarter-mile from the water or tucked into the wooded lots above Beacon Hill.
Our crew sealed a three-zone system in a Manorhaven colonial where return ducts showed that chalky white residue. Salt and humidity had eaten pinholes in the galvanized seams, causing the air handler to pull unconditioned air from the crawlspace. We used negative pressure and camera inspection to map every leak, then applied mastic and foil tape to all supply and return ducts, including long runs through an unheated attic. The homeowner left with before-and-after static pressure readings and NADCA-style documentation for work they couldn’t see. That’s the standard on every Port Washington job, because the work is invisible and the proof shouldn’t be.
Call Hollis Air Duct Hempstead for Duct Sealing in Port Washington
If your Port Washington home has rooms that never quite reach the right temperature, or your bills climb every season while the system runs constantly, the problem is probably in the ducts. We’ll inspect, write you a flat price per system, and seal every leak we find. The work is covered by our 365-Day Done Right Promise, and the documentation is yours to keep. Call (516) 559-4917 today for a free estimate.
Written by Roy Castellanos, Owner at Hollis Air Duct Hempstead, serving Port Washington and surrounding communities.