Fast, Reliable Duct Repair & Sealing Across San Antonio
Duct repair and sealing in San Antonio typically costs $280-$650 for most residential jobs, and our Duct Repair & Sealing team can usually be there same day or next day. We’ve been driving these streets since 1984 - from the narrow alleys behind King William Victorians to the tight attic hatches in Dignowity Hill row houses - and we know how San Antonio’s heat, humidity, and Hill Country pollen wear down ductwork differently than anywhere else in Texas.
Call (844) 685-6342 and you’ll reach a live person, 24 hours a day. We’ll give you an honest price before we lift a single tool, and we back every San Antonio job with our 90-Day Done Right Promise in writing.
Why Bellows Air Duct & Vent Co. Is San Antonio’s Preferred Duct Repair & Sealing Company
San Antonio homeowners don’t want a coupon that doubles at the door. They want a company that shows up when they say they will, does the work without drama, and fixes it free if something’s not right. That’s been our way for over 42 years.
We answer calls live around the clock - not voicemail, not an app. Our technicians are background-checked, uniformed, and equipped with camera inspection systems so you see inside your ducts before and after we touch them. No claims without proof.
Our upfront pricing means the number we give on the phone is the number on the invoice. We’ve turned down the bait-and-switch model since 1984, and we’re not changing now. In San Antonio’s military-heavy rental market, where properties near Fort Sam Houston and Lackland turn over every few years, that consistency matters. Landlords and long-term homeowners alike know we’ll be there when we say, and we’ll stand behind it - no paperwork, no arguing.
We carry professional-grade equipment from Nikro, Honeywell, and Abatement Technologies, the same brands serious HVAC contractors specify. Most San Antonio repairs are completed in a single visit.
Our Duct Repair & Sealing Services in San Antonio
Mastic Sealant Application
San Antonio’s limestone geology and historic settling patterns make mastic sealant with fiber mesh reinforcement one of our most called-for repairs. In neighborhoods like Dignowity Hill and Five Points, Victorian homes with limestone foundations experience differential settling that opens gaps at metal duct joints - gaps that foil tape can’t hold. We brush on professional-grade mastic and embed fiber mesh for a permanent seal that flexes with the house. Typical mastic sealing work in San Antonio runs $280-$450 for accessible trunk lines.
Flex Duct Repair
Flex duct takes a beating in San Antonio attics that regularly exceed 140°F from April through October. The inner liner cracks, insulation compresses, and the vapor barrier tears - especially in retrofitted systems where original 1980s flex runs weren’t sized for today’s heat loads. We replace damaged flex sections with properly insulated, code-compliant material and seal all connections with mastic, not tape. Last winter, we sealed a flex-duct trunk in a Government Hill rental near Fort Sam Houston that had been packed with cedar pollen and dog dander for four years between tenants. Using Rotobrush agitation and Abatement Technologies HEPA filtration, we repaired multiple tears at attic crossover points with mastic and reinforced insulation, cutting the home’s energy loss by an estimated 30%. Flex duct repair in San Antonio typically runs $320-$580 depending on attic accessibility.
Metal Duct Repair
Galvanized steel ducts in San Antonio’s older homes corrode at seams where condensation collects, and the city’s hard water minerals accelerate rust at condensate drain connections. We cut out damaged sections, fabricate replacements on-site, and seal with mastic and mechanical fasteners for a repair that outlasts the original. Metal duct repair in San Antonio generally falls between $380-$650.
Duct Insulation
Uninsulated or degraded duct insulation in San Antonio attics is like pouring cooled air into a 140°F oven. We install foil-faced fiberglass or closed-cell foam insulation at R-6 to R-8 values, sealed at all seams, to keep the air that left your handler at 55°F arriving at your register close to that temperature. Duct insulation work in San Antonio typically ranges $450-$780 for average homes.
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 San Antonio
We stock parts and materials from Honeywell, Nikro, and Abatement Technologies - brands that hold up to San Antonio’s demands. Honeywell media filters and electronic air cleaners integrate with sealed duct systems to keep cedar pollen and caliche dust from recirculating. Nikro’s contact cleaning tools and Abatement Technologies’ HEPA-negative air machines are standard on our San Antonio trucks, so we’re not waiting on a parts run from Austin while your attic sits open. That means faster turnaround and fewer return visits.
Common Duct Repair & Sealing Problems We See in San Antonio Homes
- Cedar pollen destroys tape seals. From December through February, San Antonio’s Ashe juniper pollen - the infamous “cedar fever” - accumulates in attics and forces its way through every weak point in ductwork. Duct tape adhesive softens in attic heat and fails under pollen pressure, blowing fine yellow dust through supply registers into living spaces.
- Caliche dust grinds down flex duct. Limestone construction dust from San Antonio’s constant development infiltrates leaky flex-duct joints, mixing with attic humidity to form an abrasive paste that degrades insulation and promotes mold colonization in the liner.
- Historic retrofits create impossible access. Central air was added to King William and Dignowity Hill homes decades after they were built, with ducts routed through scissor attics and balloon-frame walls that today’s technicians struggle to navigate. We carry compact equipment specifically for these tight clearances.
- Military rental turnover hides years of neglect. In Government Hill and near Fort Sam Houston, PCS cycles mean ducts often go 3-5 years between any professional attention. We regularly find separated flex runs, cracked metal boots, and registers packed solid with pet dander and pollen from multiple tenants ago.
Pricing for Duct Repair & Sealing in San Antonio, TX
Here’s what honest pricing looks like in the San Antonio market:
- Mastic sealant repair (accessible trunk lines): $280-$450
- Flex duct section replacement: $320-$580
- Metal duct repair/fabrication: $380-$650
- Duct insulation (R-6 to R-8): $450-$780
- Full system sealing with camera verification: $650-$1,100
Attic accessibility, extent of damage, and whether we can complete the work in one visit affect where you fall in these ranges. We disclose your exact price before starting - no bait coupons, no changes at the door. Estimates are free, and we honor our 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 exact number.
We Also Serve Cities Near San Antonio
Our Duct Repair & Sealing in San Antonio coverage extends to Leon Valley, Lackland Air Force Base, Converse, and Live Oak - same-day response, same upfront pricing, same 90-Day Done Right Promise. If you’re in ZIP codes 78211, 78212, 78213, or 78214, you’re in our primary service radius.
Serving San Antonio, TX - Our Local Coverage Area
We’re based in the San Antonio 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 San Antonio
Cedar pollen from December through February infiltrates every gap in your ductwork, and the fine particles act like abrasive grit against failing tape seals while building pressure that forces air through joints that held fine in cleaner months. We see the worst failures in homes near Trolley Stop in Alamo Heights and throughout the Hill Country fringe where juniper density is highest. Call (844) 685-6342 and we’ll camera-inspect your system before cedar season peaks - estimates are free.
We use mastic sealant with embedded fiber mesh, not tape, because limestone foundations settle differentially and tape cracks within a season. Our technicians work with compact tools in tight crawlspaces where these Victorians were retrofitted with ductwork decades after construction. The repair takes longer than a suburban crawlspace job, but it lasts. Most King William repairs run $380-$620. Call (844) 685-6342 for a free assessment of your specific foundation and duct routing.
Yes - we carry compact Nikro contact cleaning tools and pre-cut flex sections sized for scissor attics where headroom drops below four feet in places. We repair tears with mastic and reinforced insulation wrap, then verify with camera inspection that no gaps remain at the repaired joints. Typical Dignowity Hill flex repairs run $320-$550. Call (844) 685-6342 to schedule - we work around the parking constraints on these narrow streets.
We find separated flex runs at attic crossover points, metal duct boots rusted through from condensate backup, and supply registers packed with layered pet dander and cedar pollen from multiple tenants ago. The military turnover cycle means these systems often go 3-5 years without attention, by which point multiple failure points have developed. We camera-inspect first, show you what we find, and repair only what needs repair. Call (844) 685-6342 - we work with property managers and tenants alike, and estimates are free.
Yes - caliche dust infiltrates leaky joints and mixes with attic humidity to form an abrasive slurry that degrades tape adhesive and flex-duct insulation from the outside in. Proper mastic sealing creates a monolithic barrier that dust can’t penetrate, which is why we don’t use tape as a primary sealant on any San Antonio job. The dust is constant with the city’s development pace, so the seal has to be permanent. Call (844) 685-6342 and we’ll show you the difference camera-verified sealing makes.
Written by Ray Castillo, Owner at Bellows Air Duct & Vent Co., serving San Antonio since 1984.