Duct Sealing in Fort Collins - Tested First, Written Price Second

Fast, Reliable Duct Sealing Across Fort Collins

If your Fort Collins home has rooms that never warm up in January or cool down in July, the problem is likely air leaking from your ducts before it ever reaches the vent. In a city where forced-air heat runs seven months straight and summer highs hit the 90s at 5,000 feet, every cubic foot of conditioned air matters. Our Duct Sealing team works Fort Collins neighborhoods from Old Town to the newer subdivisions southeast of Harmony Road, and we dispatch from our Denver office with crews that know the local housing stock. Call (361) 326-5060 for a free estimate. We’ll show up inside the quoted window, put the price in writing before we touch anything, and back the work with our 365-Day Done Right Promise.

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Why Hollis Air Duct Cleaning Is Fort Collins’s Preferred Duct Sealing Company

We’ve been serving Colorado’s Front Range since 2004 as part of the Garrison Partners family, and our Fort Collins customers come back because we do what we said we’d do. Roy Castellanos built this operation on The Garrison Standard: written prices, written guarantees, and technicians who arrive uniformed, background-checked, and accountable.

Our phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops, no callback queues, no waiting until Monday to schedule. When you call (361) 326-5060, you talk to a human who can book your Fort Collins appointment or answer questions about your specific duct setup.

The crews we send to Fort Collins know the difference between a 1965 ranch near Andersonville with original sheet-metal trunk lines and a 2005 build off Timberline with flex-duct runs in the attic. That local knowledge means we diagnose faster, seal correctly the first time, and don’t waste your afternoon guessing.

Every repair is covered by our 365-Day Done Right Promise. If the seal fails within a year, we return and make it right at no charge, including a free second visit. That’s not a slogan. It’s in writing on every job.

Duct Sealing Services in Fort Collins

Duct Sealing Services in Fort Collins address the leaks, gaps, and disconnected joints that waste heated and cooled air in your forced-air system. We use professional-grade mastic sealant and metal-backed tape rated for temperature swings, applied to every accessible joint in your ductwork. A typical whole-home duct sealing in Fort Collins runs $800 – $1,800 depending on system accessibility and the extent of leakage we find. Homes with ductwork buried under slab or run through unvented crawlspaces, common in 1960s neighborhoods around Miller and Old Town, often land in the upper half of that range due to limited access.

Leak Detection and Pressure Testing

Before we seal anything, we pressurize your duct system and measure airflow loss with a calibrated fan and manometer. This gives us a hard number: how much air you’re losing to your attic, crawlspace, or wall cavities. In Fort Collins, we regularly see 20 – 35% leakage in homes built before 1980, which translates directly to higher gas bills from October through April.

Mastic Sealant Application

We apply water-based duct mastic with a brush or sprayer to every joint, seam, and penetration. Unlike duct tape, which dries and fails within a few years in Colorado’s low humidity, mastic remains flexible and bonds to metal, fiberglass, and flex-duct materials. Our crews use Guardsman-grade sealants formulated for the temperature cycling your Fort Collins ducts experience between heating and cooling seasons.

Duct Insulation in Fort Collins

Duct Insulation in Fort Collins protects the air you’ve already paid to heat or cool as it travels through unconditioned spaces. In this climate, with January nights dropping below zero and attic temperatures exceeding 130 degrees in July, uninsulated ductwork in your attic or crawlspace is like pouring money into the ground. A typical duct insulation job in Fort Collins runs $600 – $1,400 for wrapping accessible trunk and branch lines with formaldehyde-free fiberglass insulation and a vapor barrier. Homes with extensive attic ductwork, common in 1990s subdivisions south of Drake Road, often benefit most.

Attic Duct Wrapping

We wrap exposed metal or flex duct with R-6 or R-8 insulation jackets, sealed at every seam to prevent condensation during summer monsoon humidity spikes. In Fort Collins, where relative humidity can swing from 15% to 60% in a single July afternoon, proper vapor sealing matters as much as the R-value itself.

Crawlspace and Basement Runs

Ductwork in unvented crawlspaces, typical of ranch homes in the Andersonville area, loses heat to the ground and can draw in soil gases. We insulate these runs and verify seal integrity afterward, which matters especially in neighborhoods where expansive clay soils have shifted slab foundations over decades.

Trusted Brands We Service in Fort Collins

Our trucks carry sealants, tapes, and insulation from Abatement Technologies and Guardsman, plus rotary brush systems from Rotobrush and negative-air machines from Nikro for jobs that need cleaning before sealing. We stock parts for Honeywell and Aprilaire filtration systems commonly paired with ductwork in Fort Collins homes. Because we maintain inventory for the local market, most Fort Collins jobs don’t wait on shipped materials. If your system needs a specific fitting or adapter for older sheet-metal trunk lines, we source it fast and keep your project moving.

Common Duct Sealing Problems We See in Fort Collins Homes

• Disconnected flex-duct in attic spaces. In the 1990s and 2000s subdivisions south of Fort Collins, builders often used flex-duct for attic branch runs. The dry, high-UV climate here degrades the plastic liner faster than at sea level, and we find collapsed or fully separated runs that blow conditioned air straight into the insulation.
• Leaky return air plenums in 1960s ranches. Original sheet-metal returns in Old Town and Miller neighborhoods were often sealed with cloth-backed tape that has long since dried to dust. These leaks pull unfiltered air from crawlspaces or wall cavities, pressurizing your home with whatever’s down there.
• Slab duct corrosion and separation. The combination of expansive clay soils and buried ductwork in mid-century Fort Collins homes means concrete-encased metal ducts can crack, separate at joints, or fill with soil and debris. Sealing these systems sometimes requires access panel installation or rerouting, which we diagnose before quoting.
• Seasonal thermal cycling damage. Fort Collins ducts swing from delivering 120-degree air in January to 55-degree air in July. That expansion and contraction loosens joints and cracks mastic that wasn’t applied to flex properly. We see the worst failures in systems that were “sealed” with hardware-store tape five or ten years ago.

Pricing for Duct Sealing in Fort Collins, CO

We Also Serve Cities Near Fort Collins

Our crews work the full Northern Colorado corridor. We regularly schedule Duct Sealing in Fort Collins alongside jobs in Greeley, Boulder, Denver, and Colorado Springs. If you’re outside city limits in Larimer County or managing properties across multiple markets, we coordinate scheduling from our Denver office to keep everything on one invoice and one standard. We also handle Dryer Vent Cleaning in Fort Collins for homeowners bundling maintenance.

FAQs About Duct Sealing in Fort Collins