Fast, Reliable Duct Repair & Sealing Across New Braunfels
Duct repair and sealing in New Braunfels typically costs $280-$650 for most residential jobs, with same-day service available throughout the 78130, 78131, 78132, and 78135 ZIP codes. Our Duct Repair & Sealing crew handles everything from cracked mastic in attic flex runs to full metal duct restoration in the limestone homes near Gruene. Call (844) 685-6342 and you’ll reach a live person, 24 hours a day - no voicemail, no app.
We’ve been driving to New Braunfels since the early 1980s, back when I-35 was two lanes and the only traffic came from tubers on the Guadalupe. Ray Castillo built this company on showing up when we say we will and pricing the job before a single tool gets lifted. That hasn’t changed. What has changed is the city itself - one of the fastest-growing large cities in the country through the 2010s and early 2020s - and the particular problems that growth has baked into its ductwork.
Why Bellows Air Duct & Vent Co. Is New Braunfels’s Preferred Duct Repair & Sealing Company
Homeowners in New Braunfels call us because they’ve already learned the hard way. A low-bid technician shows up, quotes one price on the phone, then “discovers” problems at the door. We don’t operate that way. Our no-hassle upfront pricing means the number you hear is the number on the invoice - backed by our 90-Day Done Right Promise in writing. If it’s not right, we make it right. No paperwork, no arguing.
Our technicians are background-checked and uniformed, and they carry camera inspection equipment from Rotobrush and Abatement Technologies to document your duct condition before and after every job. Most repairs are completed in a single visit. We’ve served this region for over 42 years, and our office answers calls around the clock - not because we’re trying to be fancy, but because duct failures don’t wait for business hours. A home in Meyer Ranch with no AC in August doesn’t care about our schedule.
Ray Castillo still reviews every complaint personally. In 42 years, that hasn’t happened often. The reason is simple: we don’t leave until the camera shows the repair held, the mastic is cured, and the airflow is restored.
Our Duct Repair & Sealing Services in New Braunfels
Duct Sealing
Most New Braunfels homes built after 2010 - especially across 78132 and 78135 - lose 20 to 30 percent of conditioned air through leaks in attic duct runs before it ever reaches the living space. In tract subdivisions like Vintage Oaks and Veramendi, we’ve found supply plenums pulling attic air directly into the system because builder-grade tape failed within the first three years. Our crew seals every joint with fresh mastic and pressure-tests the system to confirm the fix. A typical duct sealing job in New Braunfels runs $280-$450 for a single system.
Flex Duct Repair
Flexible ductwork dominates the newer construction in New Braunfels, and it fails predictably. Attic temperatures in Hill Country summers routinely exceed 140 degrees, degrading the plastic liner and separating the inner core from the insulation jacket. Add caliche dust abrasion from construction debris, and we’ve replaced flex runs in four-year-old homes that should have lasted fifteen. Flex duct repair or replacement in New Braunfels typically costs $180-$340 per run, depending on length and attic accessibility.
Metal Duct Repair
The limestone and German vernacular homes in downtown New Braunfels and the Gruene corridor (78130) often retain original galvanized steel ductwork from decades past. These systems corrode at seams, separate at collars, and rattle loose from decades of vibration. We fabricate custom patches, re-weld separated joints, and seal with high-temperature mastic designed for metal substrates. Metal duct repair in these older homes generally runs $320-$580.
Duct Insulation
This is where New Braunfels’s river geography becomes critical. The Comal and Guadalupe valleys trap humidity that condenses on any duct surface cooler than the dew point - which describes every supply line in summer. Uninsulated or poorly insulated ducts sweat, saturate surrounding drywall, and create the exact conditions mold needs. We wrap repaired ducts with R-8 insulation minimum, and we upgrade existing R-4 or R-6 wraps in attics throughout 78132 and 78135. Duct insulation work in New Braunfels typically ranges from $340-$620 depending on linear footage.
Mastic Sealant Application
We recently re-sealed and insulated the flex ducts in a 2019 home in Veramendi (78132) where the builder-used mastic had cracked after only four Hill Country summers, allowing cool air to bleed into the attic and creating condensation on the trunk line. Our crew cleaned out caliche dust, applied new mastic, and wrapped the ducts with R-8 insulation to restore the system. Mastic reapplication for a full system in New Braunfels runs $260-$480.
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 New Braunfels
We stock parts and materials from Aprilaire, Abatement Technologies, and Rotobrush - the same brands serious HVAC contractors specify for commercial installations. For New Braunfels homeowners, that means no waiting on a parts run to San Antonio. Our trucks carry R-8 insulation wrap, water-based mastic, mechanical fasteners, and flex duct in standard diameters. Most jobs finish in one visit because we planned for what we’d find before we left the shop.
Common Duct Repair & Sealing Problems We See in New Braunfels Homes
- Builder mastic that cracks within three to five years. The attic heat in New Braunfels degrades water-based sealants faster than manufacturers expect. We remove failed mastic entirely and apply fresh, fiber-reinforced compound rated for 200-degree continuous exposure.
- Caliche dust blocking return-air pathways. In master-planned communities throughout 78132, HVAC systems were commissioned while earthmovers still graded adjacent lots. That fine white dust settles in trunk lines, coats blower wheels, and abrades flex duct interiors from the inside out.
- Condensation and mold from river-valley humidity. The Comal and Guadalupe sustain localized moisture levels that neighboring Seguin or San Marcos don’t match. Any compromised duct insulation becomes a condensation surface, and mold colonizes within seasons, not years.
- Crushed or kinked flex duct from construction traffic. In subdivisions like Meyer Ranch, we’ve found flex runs flattened under stored building materials or pinched by framing crews who treated temporary ductwork as disposable. Airflow drops by half. Energy bills double.
Pricing for Duct Repair & Sealing in New Braunfels, TX
We don’t do bait coupons. The price we quote is the price you pay. Here’s what duct repair and sealing costs in the New Braunfels market:
| Service | Typical Range |
|---|---|
| Duct sealing (single system) | $280-$450 |
| Flex duct repair / replacement (per run) | $180-$340 |
| Metal duct repair (fabrication + seal) | $320-$580 |
| Duct insulation upgrade (R-8 wrap) | $340-$620 |
| Mastic reapplication (full system) | $260-$480 |
| Air leak repair (localized) | $150-$280 |
Factors that move the needle: attic accessibility (truss spacing, existing insulation depth), number of supply and return branches, extent of caliche contamination requiring cleaning before sealing, and whether we find mold that needs remediation before we can seal. We inspect with a camera before quoting, so you see what we see. Estimates are free. Call (844) 685-6342 for an exact quote on your home.
Standing offers: $50 off any repair over $250. Free second opinion on any written estimate. Permanent 5% senior and veteran discount.
We Also Serve Cities Near New Braunfels
Our crews run regular routes to New Braunfels, Cibolo, Schertz, Universal City, and Live Oak. Same pricing, same 90-Day Done Right Promise, same live-answer phone line. If you’re in 78130, 78131, 78132, or 78135, we’re already in your neighborhood this week.
Serving New Braunfels, TX - Our Local Coverage Area
We’re based in the New Braunfels 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 New Braunfels
Yes - that white dust is almost certainly caliche, the calcium-carbonate-rich soil layer common to Hill Country construction sites. In New Braunfels’s fast-growing subdivisions, HVAC systems were often powered on and sealed while bulldozers still graded adjacent lots, pulling that fine dust directly into ductwork. It’s abrasive to flex duct liners and reduces airflow at return grilles. We remove it with contact vacuuming before applying new mastic or insulation. Call (844) 685-6342 and we’ll camera-inspect your system at no charge.
Every four to six years for homes in 78132 and 78135. Builder-applied mastic in these subdivisions typically cracks after three to five summers of attic exposure above 140 degrees. We recommend a camera inspection at year four to catch seal failure before it drives up your energy bills or allows condensation damage. Our $89 Seasonal Tune-Up includes a visual duct assessment. Call (844) 685-6342 to schedule.
No - attic insulation slows heat transfer through your ceiling, but it does not stop conditioned air from escaping through duct leaks. In New Braunfels, we’ve seen homeowners spend thousands on additional blown-in insulation while losing 25 percent of their cooled air into the attic through separated duct joints. Seal first, then insulate the ducts themselves if needed. The sequence matters. Call (844) 685-6342 for a camera inspection that shows exactly where your air is going.
Yes - crushed flex duct is replaceable, and we do it regularly in Meyer Ranch and similar 78132 subdivisions. We run a new flex run of matching diameter, secure it with mechanical fasteners (not tape), seal with mastic, and insulate to R-8. Most crushed runs we find are on second-floor supplies where framers stored materials during construction. The repair takes two to three hours and is usually done same-day. Call (844) 685-6342 for a free estimate.
Yes - the Comal and Guadalupe river valleys create localized humidity that raises condensation risk inside ductwork year-round. Mold grows where three conditions meet: moisture, organic material (dust), and stagnant airflow. New Braunfels’s river-driven humidity provides the moisture; caliche dust and construction debris provide the substrate; and leaky ducts create the pressure imbalances that slow airflow and let spores colonize. We don’t just clean mold - we seal the leaks and upgrade insulation to remove the moisture source. Call (844) 685-6342 for an inspection.
Ready to stop losing conditioned air to your attic? Call Bellows Air Duct & Vent Co. at (844) 685-6342 for a free estimate on duct repair and sealing in New Braunfels. We’ll show you the camera footage, quote the job before we start, and stand behind our work for 90 days - in writing, no arguing. Ray Castillo has built this company on that promise since 1984, and we’re not about to change now.
Written by Ray Castillo, Owner at Bellows Air Duct & Vent Co., serving New Braunfels since 1984.