Fast, Reliable Duct Repair & Sealing Across Randolph
Duct repair and sealing in Randolph, MA typically costs $280–$650 for most residential jobs, with same-week scheduling available throughout the 02368 ZIP code. We’re familiar with the raised-ranch and split-level stock that dominates Randolph’s neighborhoods — homes built during the town’s 1960s and 1970s build-out with original forced-air systems now pushing 50 to 60 years. Scott Gray leads our Duct Repair & Sealing crew personally, and we carry the equipment to handle metal trunk repair, flex duct replacement, and full mastic sealing in a single trip. Call (888) 597-5659 for a free estimate — we’ll give you an honest assessment of what’s actually happening behind your walls.
Why Everest Air Duct Cleaning Service Massachusetts Is Randolph’s Preferred Duct Repair & Sealing Company
We’ve worked in Randolph long enough to know the difference between a proper duct seal and a temporary fix that’ll fail by February. Scott Gray has spent 11 years specializing in air duct systems, and he still runs every job himself — the same person who answers your phone is the one crawling through your basement with a flashlight and a mastic gun.
Our 617 verified customer reviews average 4.9 stars, and that volume matters. It means we’ve delivered consistent results across hundreds of real homes, not a handful of cherry-picked projects. Randolph homeowners specifically mention our willingness to trace problems to their source — like the finished-basement leaks that generalist HVAC crews often miss entirely.
We respond to Randolph calls within the same week, sometimes next-day, because we’re based in the Boston metro area and know the Route 28 corridor well. No dispatching service sending whoever’s available. Scott handles every job personally.
Our equipment tells the rest of the story: Rotobrush brush-system technology, Nikro HEPA vacuums, and Abatement Technologies air scrubbers — the same tools commercial contractors specify, not rebranded shop-vacs. We clean it, repair it, and seal it. One company, one accountability chain.
Our Duct Repair & Sealing Services in Randolph
Mastic Sealant Application
This is our most-requested service in Randolph, and for specific reasons. The town’s 1960s and 1970s raised-ranch homes were built with galvanized sheet-metal ductwork sealed originally with cloth-backed tape or early mastic compounds. After 50–60 years of Randolph’s coastal freeze-thaw cycles and humid summers, that sealant crumbles. We remove the degraded material entirely and apply fresh, fiber-reinforced mastic sealant to every joint and seam — a permanent fix that tape alone can’t match. In uninsulated Randolph basements, this makes an immediate difference in both airflow and what you’re breathing.
Metal Duct Repair
Original galvanized trunks in Randolph’s split-levels and Cape Cods corrode at the seams, especially where condensation pools in basement cavities during humid July and August weeks. We’ve replaced entire sections of 14-inch supply trunk on homes near Highland Avenue and North Main Street, matching the gauge and routing to preserve system balance. Metal duct repair isn’t a patch — it’s structural restoration of a 50-year-old system that’s still fundamentally sound if the leaks are addressed properly.
Flex Duct Repair & Replacement
Flex duct became common in Randolph during the 1980s and 1990s renovation wave, and much of it was installed poorly — crushed at bends, pulled taut across joists, or left with unsupported sagging runs that trap debris. We find disconnected flex lines regularly in homes where basement finishing projects rerouted airflow without professional oversight. Our crew replaces damaged runs with properly sized, insulated flex duct supported every four feet to manufacturer spec.
Duct Insulation
Basement duct runs in Randolph’s older housing stock often pass through unconditioned space — behind finished walls, through bulkheads, or across crawl areas beneath additions. Without proper insulation, these metal trunks sweat in summer and bleed heat in winter, driving up utility bills and creating condensation that feeds mold growth. We install foil-faced fiberglass insulation or closed-cell wrap depending on access and clearance, sealing the thermal envelope that the original builders never completed.
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 Randolph
We stock parts and materials from Honeywell, Aprilaire, and Abatement Technologies — brands that commercial indoor air quality contractors rely on, not hardware-store generics. For Randolph homeowners, this means faster turnaround: when we find a failed component during a repair, we’re not ordering parts and rescheduling. We’ve got the right damper, register boot, or filtration media on the truck. Our Nikro HEPA vacuums and Rotobrush systems handle the cleaning side before we seal, so you’re not paying twice for separate visits.
Common Duct Repair & Sealing Problems We See in Randolph Homes
- Open plenums behind finished basement walls. Randolph’s 1970s ranch stock saw massive basement finishing in the 1980s and 1990s, and contractors routinely drywalled right over supply plenums without capping or sealing them. We find these pulling unconditioned basement air — and sometimes rodent debris — directly into the living-space duct loop, sometimes for decades before anyone traces the musty smell to its source.
- Crumbling mastic tape on original galvanized ducts. The cloth-backed tape and early compounds used in Randolph’s 1960s and 1970s construction don’t survive the town’s coastal humidity and hard freeze-thaw cycles. By year 40 or 50, it’s falling off in strips, leaving every joint leaking conditioned air into uninsulated basement cavities.
- Disconnected flex duct from past renovations. When Randolph homeowners finished basements or added rooms, branch lines were frequently shoved aside and never properly reattached. A bedroom that never heats properly, a bathroom that always smells musty — these often trace back to flex duct lying disconnected in a joist bay, blowing conditioned air into the wall cavity instead of the room.
- Seasonal condensation and mold in basement runs. Randolph sits inland on the South Shore corridor, catching humid maritime air all summer. Metal ductwork in uninsulated basements sweats, and that moisture feeds biological growth that gets distributed through the entire house every time the blower cycles.
Pricing for Duct Repair & Sealing in Randolph, MA
Most duct repair and sealing jobs in Randolph fall between $280 and $650, depending on access, material, and how far the problem has spread. Here’s what we typically see:
- Mastic sealant application (full system, accessible basement): $280–$420
- Metal duct repair (sectional replacement, one trunk line): $340–$580
- Flex duct repair or replacement (single run): $180–$320
- Duct insulation (basement trunk wrap, per linear foot): $12–$18
- Air leak detection and sealing (diagnostic + targeted repair): $260–$450
What drives cost up: finished basements with limited access requiring drywall cuts, extensive corrosion requiring multiple trunk sections, or systems that need cleaning before sealing can be effective. What keeps cost down: catching problems before they spread, and combining services in one visit. We always inspect first and quote upfront — no open-ended billing. Call (888) 597-5659 for a free estimate; we’ll give you exact numbers after seeing your specific setup.
We Also Serve Cities Near Randolph
Our service radius covers the full South Shore corridor, and we regularly schedule combined routes through Braintree, Holbrook, Canton, and Stoughton. If you’re near the Randolph line in any of these towns, the same response times and pricing structures apply — Scott handles those jobs personally too.
Serving Randolph, MA — Our Local Coverage Area
We’re based in the Randolph 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 Randolph
Original seals from that era typically fail between 25 and 40 years, meaning most 1973 systems in Randolph are running on borrowed time. The cloth-backed tape and early mastic compounds used in that construction period don’t survive decades of coastal humidity and freeze-thaw cycling. We recently sealed a 1972 split-level on Highland Avenue where a basement finishing job left a 14-inch metal supply trunk open behind drywall for years. Our crew isolated the leak, applied mastic sealant, and installed a new insulated flex connector, restoring full airflow to the master bedroom and eliminating the musty smell that had plagued the homeowners since they moved in. If your home is in this vintage, an inspection is worth scheduling — call (888) 597-5659 for a free estimate.
Yes — this is one of the most common calls we get in Randolph, and the cause is almost always an open plenum or disconnected branch behind the finished walls. The 1990s basement finishing wave here frequently buried supply trunks without proper caps or transitions, pulling humid basement air directly into your living-space duct loop. That musty smell isn’t “just basement” — it’s circulating through every room the system serves. We cut minimal access, verify the problem with a camera, and seal or reconnect properly before closing up. Call (888) 597-5659 and we’ll trace it to the source.
Very common, especially in homes that saw additions or renovations between 1985 and 2005. Flex duct was cheap and easy to install, but many Randolph contractors ran it unsupported, crushed it at bends, or left it disconnected after rerouting. We replace damaged runs with properly sized, insulated flex supported to manufacturer specification — not a patch, but a permanent fix that matches your system’s airflow requirements.
We use fiber-reinforced mastic sealant as our primary sealant, not tape — tape fails, mastic doesn’t. For Randolph’s aging galvanized systems, we brush mastic into every joint, seam, and penetration, then embed mesh tape at stress points for reinforcement. The result is a continuous, flexible seal that handles thermal expansion and the vibration these old systems produce. Tape alone is a temporary measure; we don’t install temporary measures.
Uneven heating or cooling between rooms on the same system — one bedroom that never reaches temperature, a bathroom that’s always stuffy, a register that blows weakly despite a strong blower. In Randolph’s raised-ranch layout, disconnected flex often lies in the joist bay between basement and first floor, blowing conditioned air into the wall cavity instead of the room. Homeowners sometimes report hearing airflow “somewhere in the walls” before they ever notice the temperature imbalance. We locate these with airflow measurement and camera inspection, then reconnect or replace as needed. Call (888) 597-5659 if this sounds familiar — estimates are free.
Written by Scott Gray, Owner at Everest Air Duct Cleaning Service Massachusetts, serving Randolph and the South Shore since 2013.