Duct Sealing in Seguin - Tested First, Written Price Second

Fast, Reliable Duct Sealing Across Seguin

Duct sealing in Seguin typically runs $350 – $850 for a whole-house seal on a standard residential system, with most jobs completed in a single visit. We’re Hollis Air Duct Cleaning, and our crews handle Duct Sealing in Seguin from dispatch out of our San Antonio office, with scheduling coordinated to reach Seguin properties inside our quoted arrival window. If your registers blow weak, your utility bills climbed last summer, or you smell must when the AC kicks on, leaky ductwork is the likely culprit. Call (361) 326-5060 for a free estimate with a written price before any work starts.

Call (361) 326-5060

Why Hollis Air Duct Cleaning Is Seguin’s Preferred Duct Sealing Company

We’ve been part of the Garrison Partners family since 2004, and our Duct Sealing team has worked enough Seguin homes to know the difference between a 1940s farmhouse east of the Guadalupe County Courthouse square and a 2020s build off Highway 123. Roy Castellanos built this operation on The Garrison Standard: written prices, written guarantees, and technicians who arrive uniformed, background-checked, and ready to explain what they’re doing before they open a single register.

Our phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops. No callback queues. When you schedule duct sealing in Seguin, you get a real arrival window, and we show up inside it. Every repair carries our 365-Day Done Right Promise in writing. If the seal fails within a year, we come back and make it right at no charge, including a free second visit. That guarantee is backed on paper, not promised over the phone and forgotten.

HVAC Duct Sealing in Seguin

HVAC Duct Sealing in Seguin means finding every leak, gap, and disconnected joint in your supply and return ductwork, then sealing them with mastic and mesh or specialized aerosol sealant so the air you paid to condition actually reaches your rooms. In Seguin, where HVAC systems run 8 – 10 months a year through brutal humid summers and pollen-heavy springs, even a 15% duct leakage rate can add $30 – $60 to a monthly electric bill and force your air handler to work harder than it should.

Most Seguin homeowners call us after noticing hot rooms in summer, cold spots in winter, or dust that returns within days of cleaning. Others schedule sealing after an energy audit flags leakage above 10%. A typical whole-house seal in Seguin runs $350 – $850 depending on system size, duct accessibility, and whether we’re working with accessible attic flex duct or crawling a pier-and-beam foundation near the Guadalupe River.

What the Process Looks Like

We pressurize your duct system and measure leakage with a calibrated fan. Then we seal accessible joints with mastic and reinforced mesh, reconnect separated sections, and seal register boots to the floor or ceiling. For hard-to-reach leaks, we use aerosol duct sealant that finds gaps from the inside. We test again when we’re done so you see the before-and-after numbers in writing.

When Sealing Becomes Repair

Sometimes we open a duct run and find damage too severe for sealing alone. Sagging fiberboard, rusted galvanized trunks, or collapsed flex duct need repair or replacement before sealing does any good. We flag this during inspection, explain it plainly, and give you a written price for the full scope. No surprises once work begins.

Duct Repair in Seguin

Duct Repair in Seguin addresses the physical damage that sealing alone cannot fix: crushed flex duct in attics, rusted-out galvanized supply trunks in 1950s homes, sagging fiberboard runs under pier-and-beam floors, and rodent-chewed returns in rural outbuildings. Seguin’s housing stock spans nearly a century of construction methods, and each era brings its own failure modes. Repair costs in Seguin typically range from $200 for a single flex-duct replacement to $1,200 – $1,800 for extensive galvanized trunk work in older homes.

Out on a 1940s farmhouse east of the Guadalupe County Courthouse square, our crew ran a camera inspection on the original galvanized supply trunk and found a 1950s fiberboard branch run sagging under the pier-and-beam floor, bellied low with pecan pollen, cotton-field dust, and enough standing moisture to bloom mold. We pulled negative pressure, freed the debris with agitation tools, sealed every unsealed joint with mastic and mesh, and rebalanced the registers so the air handler wasn’t fighting a dozen leaks in the supply and return ducts. The homeowner said her spring allergy symptoms eased within a week of the work.

Pier-and-Beam Challenges

Seguin’s older homes near the Guadalupe River sit on pier-and-beam foundations where 1950s-era fiberboard ductwork has sagged from decades of humidity into low spots that collect debris and moisture – a duct-sealing condition our techs almost never see in the slab-on-grade 2010s – 2020s builds along Highway 123. These bellied sections need repair or replacement before sealing, or the mastic will fail as moisture continues pooling.

Rural Property Realities

Properties on unpaved roads outside Seguin pull in dust loads that suburban systems never see. Wood heat in outbuildings, longer service drives, and extended HVAC runtime all compress the realistic maintenance interval. We see rural Seguin systems needing attention every 2 – 3 years versus 4 – 5 for tight-built city homes.

Trusted Brands We Service in Seguin

Our equipment roster includes Rotobrush rotary brush systems for mechanical agitation, Nikro negative-air machines for controlled debris extraction, and sealing products from Abatement Technologies and Guardsman. We stock common repair materials locally so Seguin jobs don’t wait on shipped parts. When we quote a repair, we specify what brand and grade of material we’re using and why it fits your system. No hardware-store tape jobs. No mystery products.

Common Duct Sealing Problems We See in Seguin Homes

• Sagged fiberboard under pier-and-beam floors. In neighborhoods near the Guadalupe River, decades of humidity have bellied 1950s fiberboard runs low enough to trap standing water. Sealing with mastic and mesh alone won’t fix it; the branch needs repair or replacement first, then sealing.
• Galvanized trunk leaks hidden from view. Older homes around the Courthouse square often have beautiful original hardwood and failing original ductwork. The real air loss is at unsealed joints buried in attics or crawl spaces, not the register boots you can see.
• Return-side grille bypasses in tight new builds. West-side Seguin subdivisions built since 2010 are well-sealed at the envelope but often have return plenums pulling air from wall cavities instead of ducted returns. The system runs constantly and still can’t keep up.
• Rural dust loading from unpaved roads and open land. Properties outside city limits see accelerated debris accumulation that forces filters and ductwork harder than the manufacturer designed for.

Pricing for Duct Sealing in Seguin, TX

We Also Serve Cities Near Seguin

Our crews regularly handle duct sealing and repair in New Braunfels, Cibolo, Schertz, and Universal City. Scheduling is coordinated from our San Antonio office with routing optimized for Seguin-area calls. Whether you’re in a historic neighborhood near the Guadalupe River or a new subdivision off Highway 123, we cover your area.

FAQs About Duct Sealing in Seguin