Duct Repair & Sealing in Seguin - We Measure the Leak Before We Quote

Fast, Reliable Duct Repair & Sealing Across Seguin

Duct repair and sealing in Seguin typically runs $280-$890 depending on whether we’re sealing accessible leaks with mastic or replacing flood-damaged flex duct in a pier-and-beam crawl space. Most Seguin jobs are scheduled within two business days, with our San Antonio office coordinating dispatch to neighborhoods from downtown’s pre-WWII blocks to the new subdivisions edging toward McQueeney. Call (830) 549-6847 for a written estimate before any work starts.

Call (830) 549-6847

We’re familiar with the specific failure patterns that show up in Seguin homes. The Guadalupe River’s path through town creates a moisture problem no nearby city faces at the same scale, and the 1970s-1990s tract housing stock on the east and south sides carries original ductwork that’s now reaching the end of its functional life. Our Duct Repair & Sealing crews have worked enough Seguin crawl spaces to know the difference between routine dust accumulation and flood-contaminated duct that needs full replacement.

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

CleanRun has served Seguin homeowners since 2013 under the H.A.V.E.N. Standard, with every job starting from a written price and ending with a documented photo record of every duct run. We’ve completed work in neighborhoods from the historic district near Court Street to newer developments along Highway 46, and our technicians are background-checked, uniformed, and identified by name before arrival, per Haven Standard Clause 3: Verified Crews.

Our 365-Day Done Right Promise applies in Seguin exactly as it does everywhere else: if the work isn’t right, we make it right, backed in writing on every job. We also offer a Free Second Opinion on any written estimate from a competitor. Bring us another company’s quote and we’ll put our number next to it in writing, no charge.

Scheduling is coordinated from our San Antonio office, with crews serving Seguin locally. All calls are answered by a live person, 24/7.

Our Duct Repair & Sealing Services in Seguin

Duct Sealing

Leaky ductwork in Seguin’s older homes wastes conditioned air into attics and crawl spaces, but the bigger problem we find is return-side leaks pulling humid Gulf air into the system. Our sealing process starts with a pressure test to locate leaks, then seals accessible joints with mastic sealant, a water-based compound that remains flexible and won’t crack like tape. In Seguin’s 1960s-1990s tract homes on the east and south sides, we often find return leaks that have been running for decades, driving up humidity and filter bypass. We document every sealed joint with before-and-after photos.

Flex Duct Repair

Flex duct in Seguin’s pier-and-beam homes collapses for two reasons: physical damage from workers in the crawl space, or moisture saturation that causes the inner liner to delaminate from the insulation jacket. Along the north-side river bend, flood water from Guadalupe crests is the primary culprit. We don’t clean flex duct that shows water staining or musty odor without first running a camera inspection and documenting the findings. When replacement is needed, we install new insulated flex duct with sealed connections, supported every four feet to prevent sagging that creates new condensation traps.

Metal Duct Repair

Seguin’s pre-WWII downtown homes with forced-air conversions often contain oversized metal plenums with deteriorating fiberglass liner. Sealing leaks with mastic over failing liner traps moisture against the metal and accelerates corrosion. Our approach is to inspect the liner condition first, document it with photos, then either repair localized damage or recommend full plenum replacement if the liner is broadly degraded. We show the customer the camera footage before quoting any scope of work.

Duct Insulation

Uninsulated or degraded duct insulation in Seguin’s unconditioned crawl spaces and attics creates condensation problems year-round, but especially during Gulf humidity surges. We replace wet or compressed insulation with new R-6 or R-8 flex duct insulation, sealed at all seams, and pay particular attention to the air handler closet where supply and return plenums connect. In flood-prone areas near the Guadalupe, we also assess whether the duct support system needs elevation to reduce future water contact.

Mastic Sealant Application

Mastic is our preferred sealing material for accessible metal duct joints and plenum connections in Seguin homes. Unlike foil tape, which degrades in high attic temperatures, mastic remains flexible and maintains its seal through thermal cycling. We apply it with a brush or caulking gun to all longitudinal seams, transverse joints, and register boots, then photograph the completed work. For homes with significant leakage, we verify the seal with a post-application pressure test.

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After

Trusted Brands We Service in Seguin

Our equipment roster includes professional-grade tools from Nikro, Honeywell, and Abatement Technologies, brands customers can look up independently to verify specifications. We stock common flex duct sizes, mastic compounds, and insulation materials for Seguin jobs, which means most repairs don’t wait on parts orders. For specialized components in older downtown systems, we source through our San Antonio supply chain with next-day availability in most cases.

Common Duct Repair & Sealing Problems We See in Seguin Homes

• Collapsed flex duct in river-bend crawl spaces. The low-lying neighborhoods along the Guadalupe’s north-side bends experience periodic flooding that forces standing water into subfloor duct cavities. Standard agitation tools can’t clean inside a soaked inner liner, and attempting to do so without confirming the contamination source repeatedly fails. We probe for musty odors and visible discoloration first.
• Oversized metal plenums with degraded fiberglass liner in downtown conversions. Seguin’s pre-WWII homes with early forced-air retrofits often feature plenums where the interior liner has begun to detach and crumble. Sealing leaks with mastic over this material traps moisture against the metal shell. We inspect with a borescope before recommending any sealant application.
• Return-side leaks pulling humid attic air in 1960s-1990s tract homes. On the east and south sides of Seguin, original return ductwork in these homes often pulls unconditioned attic air through gaps at the air handler cabinet. After sealing, we re-check static pressure to confirm the blower motor isn’t working against increased restriction.
• Cedar pollen accumulation in return systems post-February. Seguin sits at the eastern edge of the mountain cedar belt, and the heavy December-February pollen loads settle into return-air ductwork. Homeowners notice the smell persists after the season ends because the allergens have adhered to duct walls. We document the accumulation with camera footage before recommending cleaning versus replacement.

Pricing for Duct Repair & Sealing in Seguin, TX

We Also Serve Cities Near Seguin

Our crews regularly work in Seguin and the surrounding communities: New Braunfels to the north, Cibolo and Schertz to the west, and Universal City toward San Antonio. The same H.A.V.E.N. Standard, written pricing, and documented photo record apply in every city we serve.

FAQs - Duct Repair & Sealing in Seguin