Duct Sealing in Dallas - Tested First, Written Price Second

Fast, Reliable Duct Sealing Across Dallas

Duct sealing in Dallas typically runs $800 – $2,400 for a whole-home system depending on accessibility and the extent of leakage, and every Hollis job starts with a written price before we touch anything. We’re the Duct Sealing in Dallas crew homeowners call when upstairs rooms won’t cool, energy bills spike for no clear reason, or a camera inspection shows conditioned air bleeding into a 140°F attic. Our dispatch and scheduling run from the Dallas-Fort Worth office, and our technicians carry mastic, mesh, and pressure-testing gear to jobs from Oak Cliff to Frisco. Call (361) 326-5060 for a free estimate. We’ll show you your own duct photos, quote one flat price per system, and stand behind the work with our 365-Day Done Right Promise.

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

We’ve been part of the Garrison Partners family since 2004, and our Dallas-area crews have sealed ducts in pre-war bungalows off Jefferson Boulevard and in sprawling tract homes near the Sam Rayburn Tollway. That range matters. A technician who only knows one era of construction misses the failure modes of the other.

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, we arrive inside the quoted window, in uniform, with a background-checked technician whose name you know before the truck pulls up. The Garrison Code requires it.

Every repair is covered by our 365-Day Done Right Promise in writing. If the seal fails within a year, we return and make it right at no charge, including a free second visit. No negotiation, no runaround. We price in writing before any work starts, and that number does not move at the door.

Duct Insulation in Dallas

Duct Insulation in Dallas is often the missing piece when homeowners have already sealed leaks but still see temperature swings between rooms or watch their summer electric bills climb past $400. In this market, we’re insulating flexible duct runs that sit in attics exceeding 140°F for months at a stretch, and bare metal or thin-walled flex simply cannot hold conditioned air temperature across that gap. We wrap supply and return lines with formaldehyde-free fiberglass or closed-cell insulation rated for Texas attic conditions, then seal the insulation jacket with mastic to prevent vapor drive. A typical Dallas duct insulation job runs $1,200 – $2,800 for a whole system, depending on linear footage and whether we need to pull degraded old wrap first.

When Insulation Beats Replacement

We see this call most often in 1990s – 2000s Frisco and Plano homes where the flex duct itself is intact but the original insulation has compressed, torn, or cooked flat against the duct core. In those cases, re-insulating saves the homeowner a full duct replacement while restoring R-value. We photograph the before condition, quote the flat price, and show you the after.

Vapor Barriers for Humid Attics

Dallas’s humid subtropical climate means attic moisture can condense on cold duct surfaces in shoulder seasons. We specify insulation with an intact vapor barrier facing outward, sealed at every seam, so humid outside air stays outside and your conditioned air stays dry.

HVAC Duct Sealing in Dallas

HVAC Duct Sealing in Dallas addresses the leakage points that cost homeowners 20 – 30% of their conditioned air before it ever reaches a register. Our process starts with a pressure test to establish baseline leakage, followed by a camera inspection of accessible trunk lines and flex runs. We seal metal joints with mastic and fiberglass mesh, reconnect separated flex collars with mechanical fasteners plus sealant, and test again to verify the drop in leakage. A typical residential HVAC duct sealing job in Dallas runs $800 – $2,400, with simpler single-zone homes toward the lower end and multi-zone systems with attic-mounted dampers toward the higher.

Pressure Testing Before and After

We don’t guess. Our crews use a duct blaster or calibrated fan to measure actual leakage in CFM at 25 Pascals. You see the number before we start and the number after we finish. That measurement is how we know the job is done, not by eyeballing tape lines.

Zone Damper Sealing

Multi-zone systems common in Dallas’s newer suburbs have motorized dampers at trunk-line branches. Those dampers leak around their frames and can stick partially open, defeating the zone intent. We seal the damper housing and verify actuator travel so each zone gets only the air it’s supposed to.

Trusted Brands We Service in Dallas

Our trucks stock sealing and filtration products from Aprilaire, Abatement Technologies, and Guardsman, plus rotary brush systems from Rotobrush for pre-sealing cleaning when ducts are loaded with debris. We don’t run to a supply house mid-job. That means a Dallas homeowner isn’t paying for our drive time or waiting an extra day because a specific mastic or collar size wasn’t on the van. For filtration upgrades tied to sealing work, we carry Honeywell and Aprilaire media cabinets and can quote those in the same visit if your return plenum is pulling unfiltered attic air through a gap.

Common Duct Sealing Problems We See in Dallas Homes

• Crushed flex runs in 140°F attics. In Frisco, Plano, and other post-1990s suburbs, flexible ductwork sags between trusses, gets stepped on by cable installers, or collapses under its own weight where insulation has slid. The gap looks sealed from below but bleeds conditioned air into the attic all day.
• Heat-degraded tape and mastic failure. Standard duct tape or cheap mastic applied in cooler months often fails within one Dallas summer. We see registers blowing 90°F air in July because last year’s sealant turned to powder. We use products rated for sustained attic temperatures above 150°F.
• Undersized original ducts in East Dallas. Pre-war bungalows and early ranch homes near White Rock Lake have galvanized steel trunk lines sized for window units or no AC at all. When central air was added, the static pressure rose and unsealed joints now pull attic insulation fibers into living spaces.
• Disconnected collars at zone branches. Multi-zone systems have more connection points, and more connection points mean more failure points. We regularly find collars hanging open by a few inches, dumping an entire zone’s worth of cooled air above the ceiling.

Pricing for Duct Sealing in Dallas, TX

We Also Serve Cities Near Dallas

Our crews work throughout the Dallas-Fort Worth metro, including Duct Sealing calls in Irving, Duncanville, Balch Springs, and Mesquite. The same flat-price structure, the same 365-Day Done Right Promise, and the same live-answer scheduling apply in every city we serve.

FAQs About Duct Sealing in Dallas