Duct Repair & Sealing in Seguin - Tested First, Written Price Second

Fast, Reliable Duct Repair & Sealing Across Seguin

Duct repair and sealing in Seguin typically runs $340-$780 for most residential jobs, with flex-duct reattachment and collar sealing on the lower end and full-run replacement with mastic sealant on the upper end. We dispatch crews to Seguin from our San Antonio coordination office, and most Seguin appointments are scheduled within two to four business days. Call (830) 402-5110 for a written estimate before any work starts.

Call (830) 402-5110

We’ve been working in Seguin since 2013, and the pattern is consistent: the newer the house, the more likely we’re repairing flex-duct runs that never should have failed this early. The west-side and north-side subdivisions built during the 2000s-2020s boom - the ones off West Kingsbury, along Highway 46, and north of I-10 toward McQueeney - were ducted with builder-grade flex runs that sag and pull loose from boot collars after years of near-continuous May-through-September runtime. That’s not a prediction. It’s what our Duct Repair & Sealing crews find on a regular basis in Seguin.

The pecan pollen doesn’t help. Seguin sits surrounded by commercial orchards and mature shade trees, and that fine, oily spring bloom bonds to flex-duct liner walls differently than ordinary household dust. Standard brush passes leave a film. Sealing over it is pointless. The work takes longer here than it would on identical square footage in a drier Hill Country town forty miles west.

Why CleanRun Air Duct Cleaning Schertz Is Seguin’s Preferred Duct Repair & Sealing Company

We’ve served more than 52,000 homes since 2013, every one with a written price before work began and a documented photo record when the crew left. Seguin homeowners account for a growing share of our calls, particularly from the newer subdivisions where builder-grade installations are showing their age under Central Texas heat.

Tomas Reyes built CleanRun on the H.A.V.E.N. Standard, and that means Haven Standard Clause 1 applies on every Seguin job: a written price delivered before any panel comes off, with no “call for a quote” evasion. Our technicians are background-checked and uniformed, identified by name before arrival, and every job is backed by the 365-Day Done Right Promise in writing.

We don’t bury our license number in a footer. It’s published on every page, including this one, because verifiable credentials matter more than decorative badges. Our equipment roster includes Rotobrush, Nikro, and Honeywell systems - brands customers can look up independently before agreeing to a price.

Dispatch and scheduling for Seguin are coordinated from our San Antonio office, but the crews serving you are the same ones who know the difference between a McQueeney tract home and a historic-core retrofit on Court Street. Local context changes what we find and how we fix it.

Our Duct Repair & Sealing Services in Seguin

Flex Duct Repair

This is the bulk of our Seguin work. The flex runs in 2000s-2020s west-side and north-side subdivisions pull loose from boot collars, sag across joists, and dump conditioned air into attics instead of bedrooms. On a 2019 build off West Kingsbury, a homeowner called us about uneven cooling - the primary bedroom never matched the thermostat. Our tech ran a camera inspection and found the flex run to the master boot had pulled completely off the collar and was sagging across a joist. We re-secured it, sealed the collar with mastic sealant, and sealed the plenum seams while the truck-mounted negative pressure and HEPA filtration ran on the supply and return ducts. The room came back into balance on the next cycle.

The pecan-pollen film on the liner meant the homeowner scheduled the full clean afterward. Standard brush passes hadn’t touched it. That’s Seguin-specific. In Lockhart or Gonzales, the same footage would have been clean in one pass.

Mastic Sealant Application

Mastic is a water-based sealant we brush onto plenum seams, collar connections, and metal duct joints. In Seguin, we apply it after source-removal cleaning, not before. The Guadalupe River valley humidity feeds mold in debris-laden duct interiors, and sealing over that contamination traps moisture against the metal. Haven Standard Clause 1 requires the written scope to specify prep work before sealant goes on. We photograph the before condition, clean to substrate, then seal and photograph again. The photo record is part of the standard job deliverable.

Air Leak Repair

Leaks in Seguin tend to cluster at flex-to-metal transitions and at plenum seams on systems that have cycled through ten-plus years of near-continuous summer runtime. The thermal expansion loosens tape adhesive and cracks mastic that was applied too thin at install. We pressure-test the system, mark leak points with the camera running, then repair and verify. The homeowner gets the footage. Every joint, every repair, every pressure reading.

Duct Insulation

When flex-duct liner has degraded past repair or when attic temperatures in Seguin’s unconditioned spaces are cooking the supply air before it reaches the register, we replace or supplement insulation. The R-value matters more here than in cooler climates, and we use materials rated for Central Texas attic exposure. We don’t wrap over damaged liner - that’s a moisture trap. We replace the run or repair the liner first, then insulate.

Metal Duct Repair

Seguin’s historic-core homes on Court Street and around Central Park sometimes retain original galvanized metal ductwork from retrofitted central-air installs. The chases were never designed for it. We see crushed runs, improper slope causing condensate pooling, and seams that have rusted through from decades of humidity exposure. Metal repair here is fabrication work: cutting replacement sections, forming new collars, welding or sealing with mastic and fiberglass mesh. It’s slower than flex-duct repair and priced accordingly.

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Trusted Brands We Service in Seguin

Our equipment includes Rotobrush brush-and-vac systems for mechanical agitation, Nikro HEPA-filtered negative-air machines for containment, and Honeywell media filters for post-repair air quality verification. We stock common flex-duct diameters, boot collars, and mastic sealant for Seguin jobs, so most repairs don’t wait on parts. For specialized components - Aprilaire zoning dampers, for instance, or Guardsman liner repair kits - we coordinate with San Antonio supply houses and typically have them within twenty-four hours. Customers can verify every brand independently before agreeing to a price. That’s Haven Standard Clause 1.

Common Duct Repair & Sealing Problems We See in Seguin Homes

• Flex duct pulled loose from boot collars in newer subdivisions. The 2000s-2020s west-side and north-side tract homes were ducted with lightweight flex runs that sag under their own weight after years of near-continuous summer runtime. The conditioned air dumps into the attic. The bedroom stays hot. The homeowner blames the AC unit.
• Oily pecan-pollen film bonding to flex-duct liner walls. Seguin’s orchard surroundings produce a pollen load that standard brush passes leave behind. Sealing over it fails. The film has to be mechanically agitated and extracted before mastic or tape will bond properly.
• Guadalupe River valley humidity feeding mold in debris-laden ducts. The relative humidity here stays elevated compared to drier Hill Country towns, and mold colonization inside ducts turns a simple leak repair into a source-removal job first. Mastic sealant applied over active mold is a wasted application.
• Construction dust and drywall debris in new-build ducts. Seguin’s building boom produced houses handed over with ducts full of sawdust, drywall grit, and trade debris. The HVAC contractor ran the system during finishing, and the filter caught some of it - the rest packed into boot collars and settled in low points, accelerating corrosion and restricting flow before the first homeowner changed a filter.

Pricing for Duct Repair & Sealing in Seguin, TX

We Also Serve Cities Near Seguin

Our crews work throughout the northeast San Antonio corridor. If you’re in Seguin, New Braunfels, Cibolo, Schertz, or Universal City, the same H.A.V.E.N. Standard applies: written price first, documented photo record on every visit, 365-Day Done Right Promise in writing. Scheduling is coordinated from our San Antonio office, with local crews dispatched to each city.

FAQs - Duct Repair & Sealing in Seguin