Fast, Reliable Duct Repair & Sealing Across Exeter
Duct repair and sealing in Exeter typically costs $180-$650 depending on the scope, with most single-room repairs completed same-day and whole-system sealing jobs scheduled within 48 hours. We’re familiar with the stone basements and retrofit ductwork that define this town’s older housing stock, and we carry the right materials for jobs that inland contractors often underestimate.
We’ve been driving to Exeter since our trucks first rolled out in 1984. The route from our dispatch to the historic downtown core, past the Phillips Exeter Academy grounds and down Water Street, is one our technicians know without GPS. If you’re in the 03833 ZIP code, or out toward the Kingston line where the newer developments sit, we’ll give you a real arrival window and stick to it. Call (844) 685-6342 and a live person picks up, day or night.
Why Bellows Air Duct & Vent Co. Is Exeter’s Preferred Duct Repair & Sealing Company
Exeter homeowners don’t call us for flash. They call because they bought a Federal-style house on Spring Street in 1987, raised their kids there, and now the forced-air system installed in the 1970s is leaking heated air into a fieldstone basement that never fully dries out. They’ve learned that a cheap fix in a damp basement is no fix at all.
Our reputation here is built on return visits we didn’t have to make. The 90-Day Done Right Promise means if a seal fails or a repair doesn’t hold, we come back. No paperwork to file, no argument. Ray Castillo put that in writing when he founded Bellows in 1984, and it’s still how we operate.
Our response time to Exeter averages same-day for calls placed before noon, next-morning for afternoon requests. We don’t subcontract to crews from Massachusetts who don’t know that the Squamscott River’s tidal reach keeps basement humidity 15-20% higher here than in Amesbury or Merrimac. Our technicians arrive in uniform, background-checked, with Rotobrush and Abatement Technologies equipment sized for older homes with tight access.
We answer calls 24 hours a day. Not a voicemail tree. A live person who can dispatch a technician or book your free estimate while we’re talking.
Our Duct Repair & Sealing Services in Exeter
Duct Sealing
Sealing is where most Exeter jobs start, and where most go wrong if the contractor doesn’t account for local conditions. We resealed a flex-duct trunk line in a Water Street colonial where mold had colonized the mastic joints within two years of a previous contractor’s work. The homeowner showed us the original one-piece door springs-still functional from the 1940s-that we had to work around in a cramped basement. That previous contractor used standard mastic in a stone basement where tidal groundwater kept the substrate too damp for a proper cure. We stripped the failed material, applied a moisture-barrier primer, and finished with Aprilaire-compatible sealant rated for high-humidity environments. Two years later, the joints are still tight.
For Exeter homes, we specify sealants that cure in damp conditions because the Squamscott’s moisture plume doesn’t take summers off. A typical duct sealing job in Exeter runs $280-$550 for partial-system work, $650-$1,200 for whole-house sealing in larger colonials.
Flex Duct Repair
Flex duct installed in Exeter’s unheated attic chases during the 1980s and 90s is reaching the end of its structural life. Cold NH winters drive condensation on the outer vapor barrier; summer humidity swells the fiberglass insulation. After enough cycles, the duct sags, then collapses at the fitting. We’ve replaced collapsed flex runs in homes near the downtown where the original carpenter-framed chases were never meant to carry mechanical loads. Our replacement uses reinforced flex with integrated support wire, properly suspended from the chase framing rather than resting on it. Most flex duct repairs in Exeter fall between $180-$340 per run.
Metal Duct Repair
Exeter’s 1920s and 30s colonials often contain original galvanized steel ductwork that’s lasted a century because it was built thick and installed with craft. We don’t automatically recommend replacement. Where seams have opened or rust-through is localized, we fabricate patches, re-seal with high-temperature mastic, and reinforce with metal-backed tape. When the metal is too far gone, we fabricate replacement sections to match the original dimensions so the new work doesn’t disrupt airflow patterns that have balanced the house for decades. Metal duct repair in Exeter typically ranges $220-$480, with full section replacement at the higher end.
Duct Insulation
Uninsulated or degraded duct insulation is a hidden energy drain in Exeter’s older homes. We wrap exposed runs with formaldehyde-free fiberglass or closed-cell foam where space allows, paying special attention to ducts passing through unvented crawlspaces beneath 19th-century additions. Proper insulation prevents the condensation that breeds mold and reduces the load on your heating system during January cold snaps. Duct insulation work in Exeter generally runs $150-$400 per treated zone.
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.
Trusted Brands We Service in Exeter
We stock parts and materials from Abatement Technologies, Rotobrush, Aprilaire, and Guardsman on every Exeter-bound truck. This matters when your 1960s ranch near the Epping town line needs a same-day repair and the big-box stores don’t carry the right diameter flex or the proper moisture-rated mastic. We don’t make you wait for a parts run to Massachusetts. Most jobs-metal patchwork, flex replacement, full-system sealing-finish in one visit because the technician who arrives has what’s needed in the van.
Common Duct Repair & Sealing Problems We See in Exeter Homes
- Mastic sealant fails prematurely in stone basements because constant tidal moisture from the Squamscott prevents proper cure, leading to air leaks within months of application. We see this repeatedly in homes near Water Street where previous contractors applied standard sealants that never fully set.
- Retrofit duct runs through uninsulated attic chases in historic homes collapse under their own weight after winter condensation cycles, splitting flex-duct at the fittings. The original framing was never designed to support mechanical loads, and decades of thermal cycling finish the job.
- Original one-piece garage door hardware near the river corrodes from salt-laden humidity, causing spring breaks that drop the door onto ductwork passing overhead. We coordinate safe removal with our Duct Repair & Sealing team before accessing ducts in these tight basement spaces.
- Galvanized steel ducts in pre-WWII homes develop pinhole rust where condensation pools at low points, especially in ducts routed through damp stone foundations that wick groundwater year-round. The rust is often hidden by old insulation that homeowners don’t know to check.
Pricing for Duct Repair & Sealing in Exeter, NH
We show you the full price before we start. No bait coupons, no add-ons at the door. Here’s what duct repair and sealing costs in Exeter’s market:
| Service | Typical Range in Exeter |
|---|---|
| Single flex duct repair/replacement | $180 - $340 |
| Metal duct patch or section repair | $220 - $480 |
| Partial-system duct sealing | $280 - $550 |
| Duct insulation (per zone) | $150 - $400 |
| Whole-house sealing (large colonial) | $650 - $1,200 |
Exeter’s older homes often need more preparation time-removing old hardware, accessing cramped chases, working around original framing-than newer construction. We build that into the upfront quote so there are no surprises on the bill. Standing offers: $50 off any repair over $250, free second opinion on any written estimate, $89 seasonal tune-up, and a permanent 5% senior and veteran discount. Call (844) 685-6342 for your free estimate.
We Also Serve Cities Near Exeter
Our service area extends to Kingston, Seabrook, Amesbury, and Merrimac. Each town has its own housing stock and conditions-Seabrook’s coastal salt air, Kingston’s mix of historic and new construction-but Exeter‘s tidal-river moisture profile remains unique in our service territory. If you’re in one of these neighboring communities, the same technicians and the same upfront pricing apply.
Serving Exeter, NH - Our Local Coverage Area
We’re based in the Exeter 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 - Duct Repair & Sealing in Exeter
The musty odor returns because cleaning doesn’t stop the moisture source. Water Street sits in the densest part of the Squamscott River’s moisture plume, and stone foundations in this area wick tidal groundwater directly into basement air that your ducts pull from. Even with clean duct walls, the incoming air carries that mildew signature. We address this with vapor-barrier sealing at duct penetrations and, where appropriate, dehumidification recommendations for the basement itself. Call (844) 685-6342 and we’ll inspect the source.
Yes, and we replace them with reinforced flex supported from the chase framing rather than resting on it. Collapsed flex in Exeter’s attic chases is usually caused by condensation weight in winter followed by summer humidity swelling the insulation. The original installation likely lacked proper support straps. Most repairs take 2-3 hours and are done in one visit. Call for a free estimate.
We can, and we often prefer repairing original galvanized steel over replacing it with modern flex. The metal in those 1920s systems was thicker-gauge than today’s standards, and the original dimensions were balanced for the house’s airflow. We patch rusted sections, re-seal seams, and only replace what’s truly unsalvageable. A camera inspection shows you exactly what we’re working with.
We coordinate safe removal with qualified door technicians before accessing ducts in those tight spaces. Original one-piece door springs from the 1940s-50s are under extreme tension and can cause serious injury if handled improperly. We don’t cut corners on safety, and we don’t ask homeowners to move hazardous hardware themselves. Once the space is clear, our Duct Repair & Sealing team completes the repair.
Historic homes require sealants rated for damp-cure conditions, proper preparation of irregular substrates, and patience with access that new construction doesn’t demand. Exeter’s stone basements and original framing create gaps and penetrations that standard new-build methods don’t address. We also work around existing systems-original hardware, old wiring, preserved woodwork-that can’t be disturbed. The result takes longer but lasts longer because it’s done for the house you have, not a house on a spec sheet.
Ready to stop losing heated air into a damp basement and start breathing cleaner air? Call (844) 685-6342 now. A live person will answer, book your free estimate, and give you a real arrival window. We’ll show you the full price before we lift a single tool, and we back every job with our 90-Day Done Right Promise in writing. That’s been our way since 1984.
Written by Ray Castillo, Owner at Bellows Air Duct & Vent Co., serving Exeter since 1984.