Fast, Reliable Duct Repair & Sealing Across Lexington
Most duct repair in Lexington runs $180-$650 depending on whether we’re sealing accessible joints or replacing flex runs buried behind finished basement walls. Our Duct Repair & Sealing team carries the flexible rod systems and professional-grade mastic that let us complete most jobs in a single visit, even when ductwork has been boxed in by decades of renovations. We’ve been driving to Lexington since 1984, and we know the difference between a quick trunk-line seal on Woburn Street and a full flex-duct replacement in a Peacock Farm ranch where the basement was finished in 1987. Call (844) 685-6342 and we’ll give you an upfront price before we start. Estimates are free.
Why Bellows Air Duct & Vent Co. Is Lexington’s Preferred Duct Repair & Sealing Company
We’ve worked in Lexington long enough to recognize the house by the ductwork. A split-level off Marrett Road with its original 1962 galvanized trunk and a 1990s kitchen addition spliced in. A colonial revival near the Battle Green whose owner added central air in 2003 by running flex through a former chimney chase. We don’t guess. We camera-inspect before we quote, so you see what we see.
Our technicians are background-checked and uniformed, and they answer to a live person at our office 24 hours a day. Not an app. Not a callback queue. When you call (844) 685-6342, someone picks up. That’s been our way for over 42 years.
Lexington’s 02420 and 02421 ZIP codes sit within our standard service radius, and we typically schedule within 24-48 hours. We don’t bait-switch with coupon prices that balloon at the door. The number we give on the phone is the number on the invoice. And every repair is backed by our 90-Day Done Right Promise - if it’s not right, we return at no charge with no paperwork required.
Our Duct Repair & Sealing Services in Lexington
Duct Sealing
Leaky ducts waste 20-30% of conditioned air before it reaches your rooms. In Lexington’s older homes, the problem is compounded by decades of vibration, thermal expansion, and patchwork renovations. We seal with professional-grade mastic and reinforced mesh, not duct tape that dries and fails. Our process includes a pressure test to measure leakage before and after, so you know the improvement in actual CFM. A typical duct sealing job in Lexington runs $280-$480 for a single system.
Flex Duct Repair
Flex duct is the weak link in most Lexington systems. It’s crushed by storage boxes in attics, torn by rodents in crawl spaces, or simply sagging after 25 years of gravity. We replace damaged runs with insulated flex rated for the application, support it properly to prevent future sag, and seal every connection with mastic. Flex duct repair in Lexington typically costs $180-$340 per run, including access and sealing.
Metal Duct Repair
Original sheet-metal ductwork in Lexington’s 1950s-1970s homes has survived half a century, but the seams haven’t. We see separated longitudinal seams, rusted-out elbows, and holes where previous contractors drilled test ports and never sealed them. We repair with matching gauge metal, secure with S-locks or drives, and seal with mastic. Metal duct repair in Lexington runs $220-$520 depending on accessibility and extent of damage.
Duct Insulation
Uninsulated ducts in Lexington basements and crawl spaces sweat through humid July days, creating condensation that breeds mold and drips onto finished ceilings. We wrap with formaldehyde-free fiberglass insulation or closed-cell foam where space is tight, sealed with vapor-barrier jacketing. Insulation work in Lexington typically runs $4-$7 per linear foot for standard wrap applications.
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.
Trusted Brands We Service in Lexington
We stock parts and materials from Aprilaire, Abatement Technologies, and Rotobrush - the same brands serious HVAC contractors specify. For Lexington homeowners, that means no waiting on special orders for standard repairs. Our Rotobrush flexible rod systems let us access buried ductwork that rigid equipment can’t reach, which matters in Peacock Farm ranches and other neighborhoods where finished basements have enclosed original trunk lines. We carry the tools and the parts to finish in one trip. That’s how we’ve worked since 1984.
Common Duct Repair & Sealing Problems We See in Lexington Homes
- Renovation-spliced ductwork with debris-trapping dead ends. Lexington’s 1950s-1970s homes have been through three or four renovation cycles, and each contractor extended ducts differently. We find flex runs terminated into walls, dampers sealed shut with paint, and trunk lines choked to 50% capacity by splices that made sense at the time but starve rooms of airflow today.
- Mastic failure on aged sheet metal after decades of freeze-thaw cycling. Lexington’s humid continental climate pushes ducts through 100+ degree annual temperature swings. Original mastic and tape harden, crack, and separate. We remove the old material entirely and reseal with modern, flexible mastic rated for the application.
- Condensation and biofilm in uninsulated basement and crawl-space runs. Summer humidity in Lexington regularly hits 70%+, and cold supply ducts in warm basements sweat continuously. We insulate and seal to break the condensation cycle, then camera-verify the interior is clean before we close up.
- Pollen and allergen loading through open windows during April and May. Lexington’s dense tree canopy produces heavy spring pollen, and residents who open windows during mild days draw that load directly into return-air systems. Leaky return ducts in basements and wall cavities pull in additional unfiltered air, compounding the problem. Sealing returns is often the most impactful repair we can make for allergy sufferers.
Pricing for Duct Repair & Sealing in Lexington, MA
Here’s what duct repair and sealing costs in the Lexington market:
| Service | Typical Range in Lexington |
|---|---|
| Duct sealing (single system, accessible) | $280-$480 |
| Flex duct repair/replacement (per run) | $180-$340 |
| Metal duct repair (seam/elbow/patch) | $220-$520 |
| Duct insulation (per linear foot) | $4-$7 |
| Mastic sealant application (full system) | $320-$580 |
| Air leak repair (return or supply chase) | $150-$290 |
These ranges reflect actual Lexington jobs we’ve completed in 02420 and 02421. Final cost depends on accessibility, extent of damage, and whether we need to cut access panels in finished surfaces. We always camera-inspect first, show you the footage, and give an upfront price before any work begins. No bait coupons, no price changes at the door. Call (844) 685-6342 for a free estimate. We also honor our standing $50 Off Any Repair Over $250, and we always apply our permanent 5% Senior and Veteran discount to qualifying homeowners.
We Also Serve Cities Near Lexington
Our service radius covers Lexington and the surrounding communities. We regularly drive to Arlington, Bedford, Winchester, and Burlington for duct repair and sealing calls, and we carry the same flexible rod systems and heavy-duty parts that let us handle complex jobs across all five towns. Same scheduling, same upfront pricing, same 90-Day Done Right Promise.
Serving Lexington, MA - Our Local Coverage Area
We’re based in the Lexington 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 Lexington
The shallow floor cavities and finished-basement conversions in Peacock Farm ranches box in critical trunk-line sections that rigid brush equipment simply cannot reach. We recently repaired a flex duct splice in a Peacock Farm ranch where a finished basement conversion had boxed in the main trunk. Using our Rotobrush flexible rod system, we accessed a buried junction, sealed a torn flex run with mastic, and restored airflow to a master suite addition without cutting into the finished ceiling. Crews without this equipment often declare the ductwork inaccessible and patch around the problem. Call (844) 685-6342 if your Peacock Farm home has airflow issues behind finished basement walls.
Yes, if the old material is fully removed and the metal is properly prepped. Standard mastic tape fails on 50+-year-old sheet metal that has expanded and contracted through decades of New England freeze-thaw cycles. We scrape off all failed tape and brittle mastic, clean the surface to bare metal, and apply fresh flexible mastic rated for the temperature range. The repair lasts because we don’t layer new material over old failure. Our 90-Day Done Right Promise covers every seal we apply. Call (844) 685-6342 for an inspection and exact quote.
In most cases, yes, without cutting drywall. Our flexible rod systems access buried junctions through existing registers or small access panels we can conceal behind vent covers. For the minority of cases where the damage is too extensive for remote repair, we mark the precise location so a finish carpenter can make a minimal, repairable opening. We never recommend tearing out finished basement walls without exhausting every less invasive option first. Free estimates: (844) 685-6342.
We specialize in residential ductwork, not garage or barn door hardware. For duct repair in detached workshops, outbuildings, and converted barns common on Lexington’s larger lots, we carry the same professional-grade materials - insulated flex, heavy-gauge sheet metal, and high-temperature mastic - that we use in main houses. The difference is planning: these structures often have longer service drives and limited turnaround space, so we ask about access when you call. That lets us arrive with the right material quantities and avoid a second trip. Mention any outbuilding work when you schedule at (844) 685-6342.
We camera-map the system first, then trace the actual airflow path rather than assuming the original design still applies. Lexington homes with 50+-year-old ductwork that has been spliced, extended, and rerouted through three or four renovation generations require this methodical approach. We mark every dead end, every undersized splice, and every return leak on the footage, then present a repair plan that addresses the whole network rather than patching one symptom. The camera record becomes your documentation. Call (844) 685-6342 to schedule a camera inspection.
Ready to stop losing heated and cooled air through ducts that haven’t been properly sealed since the Carter administration? Call Bellows Air Duct & Vent Co. at (844) 685-6342 for a free estimate on duct repair and sealing in Lexington. We’ll camera-inspect your system, show you exactly what we find, and give you one honest price before we start. Most jobs finish in a single visit. And everything we do is backed by our 90-Day Done Right Promise - in writing, no arguing, no paperwork if you need us back.
Written by Ray Castillo, Owner at Bellows Air Duct & Vent Co., serving Lexington since 1984.