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.
Fast, Reliable Duct Sealing Across Salem
Duct sealing in Salem, MA typically runs $450 – $1,200 for a whole-home seal, depending on whether we’re working with modern sheet-metal trunk lines or the original brick flues and tar-paper chases common in pre-1900 homes. Most Salem jobs take a half day to a full day, and we always confirm what we’re actually sealing before we quote.
We’ve been driving to Salem since 2004, and our crews know the difference between a Derby Street clapboard and a North Salem Cape before they step out of the van. Dispatch is coordinated from our Boston office, but the technicians who show up at your door live in the area and have worked in the McIntire Historic District, the Point, South Salem, and every other neighborhood where the houses predate central air by a century or more. When you call (361) 326-5060, a live person answers, 24 hours a day. We’ll give you a written price before any work starts, and every seal is covered by our 365-Day Done Right Promise.
Why Hollis Air Duct Cleaning Is Salem’s Preferred Duct Sealing Company
Salem homeowners don’t need another outfit that treats their 1890s triple-decker like a suburban ranch. Our Duct Sealing team has spent two decades learning how air moves through timber-frame walls, coal-era crawl spaces, and the retrofitted chases that pass for ductwork in this city. We show up in uniform, background-checked, and on time, because The Garrison Standard doesn’t allow anything less.
Our reputation here is built on one thing: telling the truth about what we find. When a homeowner on Lafayette Street calls because their second floor never heats, we don’t assume it’s a loose joint. We run a camera. Sometimes it’s a disconnected run behind horsehair plaster. Sometimes it’s a brick flue that was never a duct to begin with. Either way, the price is written down before we touch a tool.
Calls are answered by a live person around the clock. No voicemail, no callback queue, no waiting until Monday to find out why your registers are blowing lukewarm air.
HVAC Duct Sealing in Salem
HVAC Duct Sealing in Salem starts with figuring out whether your “ducts” are actually ducts. In a city where the average house was built before 1900, we regularly open a register and find a brick flue, a tar-paper-lined kitchen chase from the 1920s, or a wall cavity that some contractor in 1978 decided to use as a return. Real duct sealing here is historical detective work before it’s mechanical work. A typical whole-home seal runs $450 – $1,200; partial seals or single-run repairs can land in the $180 – $450 range. The spread depends on accessibility, the condition of existing metalwork, and whether we’re sealing real ductwork or first converting a chase to something sealable.
What We Seal and What We Don’t
We seal sheet-metal trunk lines, spiral duct, and rigid connections with Guardsman mastic and Honeywell register gaskets. We do not seal crumbling tar paper, asbestos-wrapped transite, or brick flues that were never designed to move conditioned air. If we find that during inspection, we’ll show you the camera footage and explain what needs to happen first.
When Sealing Becomes Replacement
In Salem’s oldest homes, especially around the McIntire and Derby Street Historic Districts, we’ve seen “ducts” that are so far gone, sealing them would trap moisture and accelerate corrosion. When the salt-laden harbor air is already eating at metal joints, sealing a failing run without replacing it first is a waste of your money. We’ll tell you straight.
Duct Repair in Salem
Duct Repair in Salem often means reconnecting runs that were never properly joined in the first place. The 1920s Capes on North Salem’s fringes and the postwar bungalows sometimes have ductwork that was installed by homeowners or handymen who treated the original coal chute as a convenient path for a flex run. We’ve found crushed flex behind plaster, squirrel-chewed returns in crawl spaces built for ash removal, and supply lines that terminate in wall cavities instead of registers. Repair costs in Salem typically run $280 – $650 for a single run or connection, and $600 – $1,400 if we’re rebuilding a section of trunk line in a tight attic or crawl space.
Disconnected Runs Behind Old Walls
The horsehair plaster in Derby Street homes doesn’t forgive rough cuts. We’ve repaired dozens of runs where a previous contractor punched through, shoved in flex duct, and walked away. The connection loosens, the airflow drops, and the homeowner pays to heat their wall cavity. We open it properly, reconnect with mechanical fasteners, and seal with mastic rated for the temperature swing.
Rust and Corrosion Near the Harbor
Salty air accelerates metal fatigue. Homes within a few blocks of Salem Harbor, or on the Point where the wind carries salt inland, show rusted duct seams and corroded register boots years before inland properties. Our repairs include corrosion-resistant fasteners and sealants rated for coastal exposure, not the hardware-store tape that peels in eighteen months.
Trusted Brands We Service in Salem
We carry Guardsman mastic, Honeywell register gaskets, and Aprilaire filtration components on every Salem truck, which means most repairs don’t wait on parts. Our rotary brush systems from Rotobrush and negative-air machines from Nikro are the same tools commercial crews use in hospitals and schools, and we maintain them to The Garrison Standard: cleaned, calibrated, and inspected before every job. If your system uses Abatement Technologies filtration or Guardsman sealants, we stock those too. The goal is one visit, done right, with no callback because a gasket didn’t fit or a mastic tube was dry.
Common Duct Sealing Problems We See in Salem Homes
- Brick flues mistaken for ducts. In 17th- and 18th-century homes around the McIntire District, we regularly find homeowners who’ve been trying to seal what is actually an original chimney flue. The mortar is porous, the surface is irregular, and no mastic will bond to it. We identify the real airflow path and redirect.
- Tar-paper chases crumbling inside walls. The 1920s retrofits in South Salem and the Point used tar-paper-lined wall cavities as duct chases. Ninety years later, that tar paper is desiccated, and any seal applied to it will fail within a season. We remove what we can and rebuild with proper metal duct.
- Condensation in unconditioned crawl spaces. Salem’s cold winters and humid summers mean crawl spaces built for coal delivery, not HVAC, develop condensation on any metal surface. Sealing a duct without addressing the envelope just traps that moisture against the joint. We flag it and explain your options.
- Wildlife damage in chimney-converted chases. A surprising number of Salem duct calls end with our technician pulling a decades-old bird’s nest or a desiccated squirrel from a duct. Pre-1900 homes had no central air; their first systems were routed through existing chimneys and wall cavities that wildlife had claimed long before the furnace arrived.
Pricing for Duct Sealing in Salem, MA
Whole-home duct sealing in Salem runs $450 – $1,200. Single-run repairs or partial seals land at $180 – $450. Duct repair, when we’re reconnecting or replacing sections of trunk line, typically costs $280 – $650 for a localized fix and $600 – $1,400 for more extensive rebuilds in tight spaces.
What moves you within those ranges? Three things: accessibility (a crawl space built in 1880 costs more time than a modern basement), the condition of existing metalwork (rust removal and prep add labor), and whether we’re sealing actual ducts or first converting a chase or flue to something sealable. We inspect with a camera before we quote, and the price we write down is the price you pay. No per-vent add-ons, no “we found another problem” surcharges once the van is in your driveway.
Every estimate is free. Call (361) 326-5060 and we’ll schedule a camera inspection, show you what we find, and give you a written number you can compare.
We Also Serve Cities Near Salem
Our crews work throughout the North Shore. If you’re in Marblehead, Swampscott, Peabody, or Beverly, the same technicians, the same equipment, and the same written guarantee apply. We schedule Salem and neighboring towns from our Boston office to keep routes tight and arrival windows honest.
Serving Salem, MA - Our Local Coverage Area
We’re based in the Salem 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 Salem
Yes, but only after we confirm what’s actually there. Sealing a real sheet-metal duct saves 20 – 30% on heating and cooling costs. Sealing a brick flue or tar-paper chase is throwing money away. We run a camera first, show you the footage, and quote only for work that will actually hold air. Call (361) 326-5060 for a free inspection.
Those neighborhoods are dense with 19th-century tenements and triple-deckers where the first central air systems were installed by routing flex duct through existing chimney chases and wall cavities. Wildlife had occupied those spaces for decades before the HVAC contractor arrived. We remove the debris under negative pressure with HEPA filtration, then seal only the legitimate ductwork. It’s a common enough find that we budget time for it.
Salt-laden air accelerates corrosion on metal duct seams and register boots, particularly in homes within a few blocks of Salem Harbor or on the Point where prevailing winds carry spray inland. We’ve seen rusted-through trunks in fifteen-year-old systems that would last thirty inland. Our repairs use corrosion-resistant fasteners and coastal-rated sealants, and we’ll tell you if the environment means more frequent inspection is worth budgeting for.
We arrive in the quoted window, in uniform, with a background-checked technician. We inspect every accessible run with a camera, identify what’s real ductwork and what isn’t, and show you the footage. We write down the scope and price before touching a tool. Then we seal with Guardsman mastic and Honeywell gaskets, test airflow at each register, and leave the site clean. The whole job is covered by our 365-Day Done Right Promise. Call (361) 326-5060 to schedule.
Not exactly. Those Capes and bungalows usually have actual sheet-metal ductwork, but it’s often undersized for modern heat pumps, poorly insulated in unconditioned attics, and prone to condensation failure in Salem’s humid summers and cold winters. The sealing challenge is less “what is this thing” and more “this duct is too small and too cold.” We seal what we can and flag the sizing issues so you’re not surprised when the second floor still struggles.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Salem and the North Shore since 2004.




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