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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After
Before
After
Before
AfterFast, Reliable Duct Sealing Across Norwalk
Most Norwalk duct sealing calls we run start the same way: a homeowner notices dust pouring from registers right after a cleaning, or rooms that never cool evenly despite a new AC unit. The real problem is usually in the attic, not the vents. In Norwalk’s 1950s tract neighborhoods, original galvanized steel ductwork has been baking in uninsulated attics for seventy years, and the seals have long since failed. We’re the Duct Sealing team at Hollis Air Duct Cleaning, and we serve Norwalk from our Hartford office with background-checked, uniformed technicians who arrive inside the quoted window and price every job in writing before touching a tool. Call (361) 326-5060 for a free estimate, or read on to see what we actually find in Norwalk attics and what it costs to fix.
Why Hollis Air Duct Cleaning Is Norwalk’s Preferred Duct Sealing Company
We’ve been in business since 2004 as part of the Garrison Partners family, and our Norwalk customers come back because we show them camera footage of their crushed or disconnected runs before we quote a price. No guessing. No bait-and-switch. The 365-Day Done Right Promise covers every sealing job in writing: if a joint we sealed opens up or a reconnected run separates within a year, we return and make it right at no charge, including a free second visit.
Our technicians are background-checked and uniformed under The Garrison Code, and our phones are answered by a live person 24 hours a day, 7 days a week. Scheduling runs from our Hartford office, but the crews serving Norwalk know the local housing stock: the single-story wood-framed tracts off Connecticut Avenue, the low-pitched roofs in Norwalk Park, the original galvanized systems that rust through at the collars. That local knowledge means we bring the right equipment the first time: Rotobrush rotary brush systems for source removal, Nikro negative-air machines for containment, and professional-grade sealing mastic rated for attic temperatures that regularly hit 140°F in July and August.
Duct Sealing Services in Norwalk
Duct Sealing Services in Norwalk address a problem most homeowners don’t know they have until a technician opens the attic hatch. The original foil tape and mastic on 1950s galvanized steel joints has baked brittle after decades in uninsulated attic heat. Every seam peels open. Conditioned air leaks into the attic. Dust, fiberglass, and rodent debris get pulled into the supply air your family breathes. We seal with high-temperature mastic and mechanical fasteners, reconnect crushed runs, and close rodent entry points so the system holds pressure.
A typical duct sealing job in Norwalk runs $450 – $950 for a single-system home, depending on how many joints have failed and whether we need to rebuild crushed sections. Whole-home resealing on larger systems or homes with multiple attic access points can reach $1,200 – $1,800. We write the price down before any work starts, and it does not move at the door.
Attic Joint Sealing and Reconnection
On a 1,200 sq ft 1950s tract house off Norwalk Park, our tech ran a camera inspection and found three crushed return runs under the original low-pitched roof, plus mastic crumbled to powder at the air handler collar from two summers of attic heat. After source removal with Rotobrush agitation tools under negative pressure and HEPA filtration, we sealed the joints, reconnected the crushed runs, and the homeowner’s static pressure dropped enough that the blower motor stopped short-cycling. That is the difference sealing makes when it is done right.
Rodent Entry Point Closure
Norwalk’s older neighborhoods back onto fields and greenbelts where rodents travel. They chew through failed mastic at duct collars and boot connections. We close these entry points with metal flashing and sealed mastic, not just foam that they chew through again. Without this step, debris and pest contamination return within a season no matter how thorough the cleaning.
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 Norwalk
Duct Insulation in Norwalk is the companion job to sealing, and in most 1950s tract homes it is long overdue. The original fiberglass wrap has disintegrated. Bare galvanized steel runs through 140°F attic air in summer, bleeding cooled air before it reaches your bedrooms. In winter, the same uninsulated metal sweats condensation that rusts through seams from the outside. We wrap sealed ducts with formaldehyde-free fiberglass insulation rated for the temperature swings Norwalk attics see, then seal the vapor barrier so moisture stays out.
Duct insulation in Norwalk typically adds $300 – $600 to a sealing job for a single-system home, or $700 – $1,400 for full replacement of degraded wrap on all accessible runs. We only quote insulation after we have inspected what is actually in your attic, because some homes have partial retrofits that can be salvaged and others have bare metal that needs complete wrapping.
Condensation and Rust Prevention
Uninsulated galvanized steel in a hot, humid attic sweats at the seams. That moisture rusts the metal from the outside while dust cakes the inside. We see this pattern repeatedly in Norwalk homes near the Merritt Parkway corridor where summer humidity spikes. Proper insulation with an intact vapor barrier stops the condensation cycle and protects the sealing work we do.
Energy Loss Reduction
Sealed but uninsulated ducts in a 140°F attic can still lose 20 – 30% of cooled air before it reaches your registers. That is money you pay the utility for air that never cools your living room. Insulation completes the fix that sealing starts.
Trusted Brands We Service in Norwalk
Our equipment roster includes Rotobrush rotary brush systems for mechanical agitation of debris, Nikro negative-air machines that maintain containment during cleaning and sealing, and professional-grade filtration and sealing products from Abatement Technologies and Guardsman. We stock sealing mastic rated for sustained 180°F exposure because standard hardware-store products fail within two summers in a Norwalk attic. For homeowners with integrated filtration systems, we also carry Honeywell and Aprilaire components. Parts are stocked locally for Norwalk customers, so we are not waiting on a warehouse shipment while your attic hatch sits open.
Common Duct Sealing Problems We See in Norwalk Homes
- Brittle duct tape at every joint. The foil tape applied in the 1950s or during a 1980s retrofit has baked to flakes in uninsulated attic heat. We peel off the residue and seal with high-temperature mastic that flexes instead of cracking.
- Crushed return runs under low-pitched roofs. Original 1950s tracts in Norwalk Park and nearby neighborhoods have shallow attic spaces where ducts were crammed under rafters. Over decades, the metal collapses. The registers still blow, so homeowners do not notice the leak until a camera inspection shows the air handler pulling 130°F attic air instead of return air from the house.
- Rodent entry at collar and boot connections. Fields and greenbelts behind older Norwalk neighborhoods provide rodent highways into attics. They target the softest entry point: failed mastic at duct connections. We find droppings, nesting material, and chewed fiberglass in roughly one-third of the 1950s tracts we inspect.
- Rust-through at galvanized seams. Norwalk’s warm summers and mild winters mean HVAC runs heavily for cooling from May through October, pulling humid attic air over cold metal. The condensation rusts galvanized steel from the outside, opening pinholes that leak air and whistle audibly when the blower cycles on.
Pricing for Duct Sealing in Norwalk, CT
We give honest whole-system pricing, not per-vent teaser rates that balloon once the van is in your driveway.
| Service | Typical Range in Norwalk |
|---|---|
| Basic duct sealing (single system, accessible attic) | $450 – $950 |
| Sealing with crushed-run reconstruction | $800 – $1,400 |
| Whole-home resealing with multiple access points | $1,200 – $1,800 |
| Duct insulation (add to sealing job) | $300 – $600 |
| Full insulation replacement on all accessible runs | $700 – $1,400 |
What moves the price: how many joints have failed, whether crushed runs need reconstruction, attic accessibility, and whether rodent damage requires metal flashing work. We inspect with a camera, show you the footage, and write the price down before any work starts. The price does not move at the door. Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Norwalk
Our crews also run Duct Sealing in Norwalk and surrounding areas including New Canaan, Stamford, Old Greenwich, and Georgetown. Each job follows The Garrison Standard: arrive inside the quoted window, price in writing, complete the work by the book, leave the site clean.
Serving Norwalk, CT - Our Local Coverage Area
We’re based in the Norwalk 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 Norwalk
You likely need both, but sealing is often the more important fix. In Norwalk’s 1950s tract homes, the original galvanized steel supply and return ducts were often run through uninsulated attics that hit 140°F in summer, so the failure we seal is rarely a single hole – it’s failed duct tape and mastic at every joint, plus rodent entry points chewed in from nearby fields. A cleaning removes the debris, but without sealing, new contamination pulls in within weeks. Call (361) 326-5060 and we will camera-inspect to show you exactly what is open in your attic.
The system is pulling attic air and debris through unsealed joints. In Norwalk’s older neighborhoods like Norwalk Park, we see this constantly: a thorough cleaning leaves registers spotless, but within a month dust returns because the blower is sucking fiberglass, rodent droppings, and 130°F attic air through gaps at the air handler collar and crushed return runs. Sealing closes those pathways permanently. We can show you the leak points on camera before you decide.
Most 1950s galvanized steel in Norwalk can be sealed if the metal is structurally intact. We replace individual sections that have rusted through or collapsed, but full duct replacement is rarely necessary unless the homeowner is already remodeling. Our approach is to seal and局部 repair what exists, which typically costs 40 – 60% less than full replacement. We will tell you honestly if your system is past saving.
Yes, significantly. Norwalk’s warm, dry summers mean HVAC systems run heavily for cooling from May through October, pulling in dust from nearby freeways and dry, dusty yards. Sealed ducts draw 100% of their return air from inside your home instead of from a dusty attic, so less outdoor particulate circulates through your living space. The improvement is especially noticeable for households near I-95 or the Merritt Parkway corridor.
Signs include musty or ammonia-like odors when the blower runs, scattered debris at registers, or insulation fragments in the supply air. In Norwalk’s 1950s tracts near fields and greenbelts, we find active or past rodent entry in roughly one-third of attic inspections. Our camera shows chew marks at collar connections and nesting material in the plenum. We seal with metal flashing and high-temperature mastic that rodents cannot penetrate, then verify with a pressure test. Call (361) 326-5060 for a free inspection if you suspect rodent damage.
Ready to stop losing cooled air to your attic and breathing dust that should have been filtered out? Call Hollis Air Duct Cleaning at (361) 326-5060 for a free camera inspection and written estimate. We will show you what is failing in your Norwalk attic, quote one flat price per system before any work starts, and back every sealed joint with our 365-Day Done Right Promise in writing.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Norwalk since 2004.