Fast, Reliable Duct Repair & Sealing Across Severn
Duct repair and sealing in Severn, MD typically costs $180-$650 depending on whether you need flex duct replacement, mastic sealing of metal trunks, or full insulation wrap, and most jobs are completed in a single visit. If you’re noticing weak airflow, musty smells from your registers, or rooms that never reach the set temperature, the problem is likely in your ductwork, not your HVAC unit. Call Bellows Air Duct & Vent Co. at (844) 685-6342 for a free estimate with upfront pricing before any work begins.
We’ve been driving to Severn since 1984, long before the Route 100 corridor filled in and well before the BRAC expansion at Fort Meade reshaped the local housing market. Our technicians know the difference between a 1976 split-foyer off Telegraph Road and a 1992 townhome cluster near the NSA perimeter, and they know what those different eras of construction mean for the ductwork hidden above your ceiling. We answer calls 24 hours a day, and we keep parts stocked for the brands most common in Anne Arundel County so we’re not ordering components while your house stays uncomfortable.
Why Bellows Air Duct & Vent Co. Is Severn’s Preferred Duct Repair & Sealing Company
Severn homeowners have called us back for 42 years because we show up when we say we will and we leave the job done right. Our Duct Repair & Sealing team has worked in colonial homes near Waterbury Road, split-foyers off New Ridge Road, and townhome courts throughout the 21144 zip code. We know the local inspector requirements and the specific ways Chesapeake Bay humidity attacks duct systems in this watershed.
Our customers in Severn leave reviews that mention the same things: camera footage shown before and after, the technician explaining what failed and why, and a final price that matched the phone quote. We’re not the cheapest call you can make. We’re the call you make once.
Response time to Severn is typically same-day or next-day, and we do not use subcontractors. Every technician is background-checked, uniformed, and arrives in a marked Bellows van with Rotobrush and Nikro equipment on board. When you call (844) 685-6342, a live person answers, not a voicemail tree.
Ray Castillo, who leads this company, set the standard in 1984: one honest price shown before we start, camera-verified results every time, and a 90-Day Done Right Promise stamped on every job. No arguing, no paperwork if something needs correction. We stand behind it because we always have.
Our Duct Repair & Sealing Services in Severn
Mastic Sealant Application
Mastic sealant is the only proper way to close leaks in metal duct trunks and plenums, but it fails if the surface is wet. In Severn, chronic condensation from 75-85% summer humidity often keeps metal ducts damp enough that standard mastic won’t adhere. We use Abatement Technologies sealants rated for high-moisture environments, and we verify surface dryness with moisture meters before application. A typical mastic sealing job on a Severn home’s metal trunk runs $280-$450.
Flex Duct Repair
Flex duct is the black corrugated tubing common in Severn attics from the 1970s through the 1990s, and it was never designed to last 40 years. The fiberglass liner inside degrades, the wire helix rusts in humid attics, and the sagging tube pulls away from collars at the plenum. We replace damaged flex runs with new insulated duct sized to your system’s CFM requirements, secure it with proper supports every 4 feet, and seal every joint with mastic. Flex duct repair in Severn typically runs $180-$340 per run, with most homes needing 2-4 runs addressed.
Metal Duct Repair
Older Severn homes with galvanized steel trunks suffer from seam separation and rust-through at low points where condensation pools. We cut out damaged sections, fabricate replacement pieces on site, and weld or mechanically fasten them before sealing with mastic and fiberglass mesh. Metal repair is more involved than flex replacement, running $350-$650 depending on accessibility and extent of corrosion.
Duct Insulation
Unconditioned attics in Severn are brutal in July and August. When 55-degree supply air passes through a duct with degraded insulation, it sweats on the outside and loses its cooling power before reaching your bedroom. We install new foil-faced fiberglass wrap or closed-cell foam insulation around existing metal trunks, and we replace wet or compressed insulation on flex runs. Proper insulation pays for itself in reduced runtime and prevents the condensation that starts mold growth. Duct insulation in Severn runs $400-$800 for a typical single-system home.
What happens when you call
- 1
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 Severn
We stock parts and use equipment from Aprilaire, Abatement Technologies, and Rotobrush, the same brands serious HVAC contractors specify for Maryland’s climate. Aprilaire humidistats and air cleaners integrate directly with duct systems we seal, and Abatement Technologies HEPA-filtered vacuums capture the microbial debris we dislodge from 30-year-old flex duct. Rotobrush mechanical brush systems scrub duct interiors without damaging aging fiberglass liner. We don’t have to order these parts from a warehouse across the country. They’re on our vans or in our local inventory, which means your job in Severn gets done in one visit, not two.
Common Duct Repair & Sealing Problems We See in Severn Homes
- Flex duct sag in unconditioned attics. The 1970s-1990s flex duct in Severn’s colonial and split-foyer homes was hung with inadequate supports. Humidity-weakened liner lets the tube belly downward, creating low spots where debris collects and joints pull apart. We see this on Waterbury Road, on New Ridge Road, and throughout the townhome courts near the Fort Meade perimeter.
- Mastic sealant failure on metal trunks. Chronic condensation from Chesapeake Bay humidity prevents proper adhesion on poorly insulated metal ducts. Homeowners call us after “sealing” done by a general handyman has peeled away within a season. We dry, prep, and use moisture-rated sealants.
- Mold colonization at register faces. Landlord-owned properties near Fort Meade have cycled through 4-6 military-family tenants with no duct cleaning between rotations. Pet dander, cooking grease, and damp Maryland air in 30-year-old flex duct produces visible mold that Anne Arundel County home inspectors now flag on re-sale inspections.
- Insulation degradation in attic runs. Original fiberglass wrap on metal trunks compresses and falls away after decades, exposing bare metal to attic temperatures that can exceed 140 degrees in August. The air inside never reaches its destination temperature, and the homeowner blames the AC unit.
Pricing for Duct Repair & Sealing in Severn, MD
| Service | Typical Range in Severn | Most Common Price Point |
|---|---|---|
| Flex duct repair (per run) | $180-$340 | $260 |
| Mastic sealant (metal trunk, up to 20 ft) | $280-$450 | $365 |
| Metal duct repair (section replacement) | $350-$650 | $495 |
| Duct insulation (full system wrap) | $400-$800 | $595 |
| Air leak detection and sealing (whole system) | $450-$750 | $595 |
What moves you within these ranges? Accessibility (crawl space vs. walk-up attic), extent of damage, and whether we’re addressing microbial contamination alongside mechanical repair. We show you camera footage of what we found, explain exactly what needs doing, and give you the full price before we lift a tool. No bait coupons, no price changes at the door. We also offer $50 off any repair over $250, and a free second opinion on any written estimate you’ve already received.
We Also Serve Cities Near Severn
Our service area covers the full Anne Arundel corridor, including Severn and the communities immediately surrounding it. We regularly dispatch to Fort Meade for military housing ductwork, Hanover for the newer construction off Ridge Road, Odenton for the townhome developments near the MARC station, and Ferndale for the post-war homes along Broadview Boulevard. Same standards, same upfront pricing, same 90-Day Done Right Promise.
Serving Severn, MD - Our Local Coverage Area
We’re based in the Severn 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 Severn
They sag because the fiberglass liner inside degrades from chronic humidity exposure, and the wire helix rusts, losing its tension. In Severn’s 75-85% summer humidity, this happens faster than in drier inland Maryland. The duct bellys downward, debris collects in the low spot, and the joint at the plenum separates. We replace the damaged run with new supported flex duct and seal it properly so it stays put. Call (844) 685-6342 for a camera inspection - estimates are free.
Yes, if your ducts run through an unconditioned attic or crawl space. In Severn, leaky return ducts pull 140-degree attic air into your system in summer, and leaky supply ducts lose 20-30% of your conditioned air before it reaches the room. Your system works harder, your bills climb, and the humidity difference creates condensation that feeds mold. Sealing fixes all three problems. We’ll test your system and show you the leakage rate before you decide.
It means your ductwork may have accumulated 12-15 years of pet dander, cooking grease, and dust from 4-6 different families with no professional cleaning between rotations. In Severn’s damp climate, that bio-load colonizes with mold inside flex duct that a new tenant’s home inspector is increasingly likely to flag. We clean the interior bio-film, repair or replace damaged runs, and seal the system so it starts fresh for the next occupant - or for you, if you’re staying put.
Sealing alone won’t fix it if the smell comes from mold inside the duct. In Severn, musty registers usually mean moisture has activated spores in aging flex duct liner, especially in homes built 1975-1995. We camera-inspect first. If we find bio-film, we clean with HEPA-contained brushing and apply sanitizing treatment, then seal the leaks that let humidity enter. Sealing without cleaning traps the problem inside. We do both, and we show you before-and-after footage.
Most home warranties cover ductwork only if the failure is due to normal wear within the contract period, and they often exclude pre-existing conditions or microbial damage. In Severn, 30-year-old flex duct with mold contamination is frequently denied as “lack of maintenance.” We provide a free second opinion on any written estimate or denial, and our camera documentation often helps homeowners prove the failure mode to their warranty company. Call us before you call them.
Ready to get your ductwork fixed right? Call Bellows Air Duct & Vent Co. at (844) 685-6342 for a free estimate with upfront pricing. We’ll be there when we say, we’ll show you exactly what we found, and we’ll stand behind the work for 90 days with no paperwork if anything needs adjustment. That’s the square deal we’ve offered Severn homeowners since 1984.
Written by Ray Castillo, Owner at Bellows Air Duct & Vent Co., serving Severn since 1984.