Whole-system duct and dryer vent check with before-and-after photos - you see exactly what came out of your vents
That "$99 whole-house special" is a bait ad - the real number appears once they are in your hallway, or the "clean" is a shop-vac at the register. We photograph the inside of your ducts before and after instead.
Fast, Reliable Duct Sealing Across Cloverleaf
Duct sealing in Cloverleaf typically runs $850 – $1,800 for a whole-home system and usually takes one full day to complete properly. If your vents blow musty air after a Gulf Coast downpour or your energy bills keep climbing despite a new AC unit, the problem is likely air leaking from corroded ductwork, not the equipment itself.
We’re the Duct Sealing crew that serves Cloverleaf from our Houston dispatch office, and we know the local housing stock inside out. Most homes here were built between 1960 and 1980 with original galvanized steel ductwork on slab foundations – duct runs that corrode from the inside out and develop pinhole leaks most homeowners never see until the musty smell or the utility bill forces the issue. Our technicians arrive in uniform, background-checked, and ready to show you exactly what’s happening inside your system before any work starts. Call (361) 326-5060 for a free estimate.
Why Hollis Air Duct Cleaning Is Cloverleaf’s Preferred Duct Sealing Company
Hollis Air Duct Cleaning has been part of the Garrison Partners family since 2004, and we’ve built our reputation in Cloverleaf on one thing: doing what we said we’d do, at the price we wrote down, with a guarantee that lasts a full year. The 365-Day Done Right Promise means if our seal fails, we come back and make it right at no charge, including a free second visit. That’s not a verbal promise; it’s written on every job.
Our technicians are background-checked and uniformed, and they operate under The Garrison Standard: arrive inside the quoted window, price in writing before touching anything, complete the job by the book, and leave the site clean. 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 for someone to call you back.
We don’t compete on the lowest teaser price. We compete on discipline. In Cloverleaf, that means understanding the difference between a real sealing job and a fogging sanitizer upsell – because with this area’s refinery-adjacent humidity and original steel ductwork, the wrong approach wastes your money and leaves the real problem untouched.
Duct Repair in Cloverleaf
Duct Repair in Cloverleaf often starts with a homeowner noticing uneven temperatures between rooms, a sudden spike in their electric bill, or that persistent musty smell that returns every time the humidity spikes. The repair process here is different from newer suburbs because most Cloverleaf homes still run on original galvanized steel ductwork that corrodes from the inside out, creating pinhole leaks and rust flakes that flex-duct systems simply don’t develop.
We begin every duct repair with a camera inspection to map the damage. Then we remove loose rust and debris using agitation tools with HEPA filtration under negative pressure – never just blowing it deeper into the system. Only after the duct surface is clean and stable do we apply sealant. Skipping the prep work is why cheap repairs fail within months in this climate.
When Repair Becomes Replacement
Sometimes the galvanized steel is too far gone. If our camera shows sections where corrosion has eaten through the metal or the duct has collapsed from rust, we’ll tell you straight and price a replacement section in writing before any cutting starts. No surprises at the door.
Pressure Testing After Repair
Every duct repair we complete in Cloverleaf gets a post-repair pressure test. We seal the system, pressurize it, and measure how much air escapes. If it doesn’t hold, we find the leak and fix it. The Garrison Standard requires proof the job worked, not just a handshake.
Air Duct Sealing in Cloverleaf
Air Duct Sealing in Cloverleaf is the single most effective way to stop conditioned air from leaking into your attic, crawl space, or walls before it ever reaches your vents. In a typical Cloverleaf ranch home with 1960s – 1980s galvanized steel ductwork, we regularly measure 25 – 40% air loss through pinhole leaks and corroded joints – air you’re paying to cool that never makes it to your living room.
Our sealing process addresses the specific failure modes we see here. We don’t fog a sanitizer and call it sealed. We physically access the duct runs, remove rust flakes and debris, then apply a duct-specific mastic sealant rated for the temperature swings and humidity loads of Gulf Coast HVAC systems. The result is a pressure-tested system that holds its seal through the muggy summer months when Cloverleaf’s humidity pushes above 70% for weeks at a time.
Mastic Versus Tape
We use mastic sealant, not duct tape, on every Cloverleaf job. Duct tape dries out and fails in high humidity; mastic remains flexible and bonds to corroded steel in ways tape cannot. It’s slower to apply. It costs more in material and labor. It also lasts.
The Attic and Crawl Space Factor
Many Cloverleaf homes have duct runs passing through unconditioned attic space. In July, that attic hits 140°F. Every pinhole leak pulls superheated air into the system, forcing your AC to work harder for longer. Sealing those runs cuts the load and extends equipment life.
Trusted Brands We Service in Cloverleaf
We stock parts and filtration products from Aprilaire, Abatement Technologies, and Guardsman for Cloverleaf homeowners, which means faster turnaround when your system needs compatible components. Our equipment roster includes Rotobrush rotary brush systems for thorough duct agitation and Nikro negative-air machines that maintain proper containment during cleaning and sealing operations. We don’t show up with hardware-store gear. We use the same professional-grade tools commercial crews rely on, and we explain what each piece does before we start it up in your home.
Common Duct Sealing Problems We See in Cloverleaf Homes
- Pinhole leaks in corroded galvanized steel. The original ductwork in most Cloverleaf ranches has been slowly rusting from the inside since the 1970s. Moisture condenses on the cool metal, combines with dust and chemical particulates from the nearby petrochemical corridor, and eats tiny holes that add up to massive air loss.
- Failed DIY tape repairs. Homeowners or handymen often wrap leaking joints with duct tape, which turns brittle and falls off within one humid Cloverleaf summer. We remove the old tape residue entirely before applying mastic, because sealant won’t bond to adhesive residue.
- Saturated duct insulation. After heavy rains or during prolonged humidity spikes, insulation surrounding metal ductwork absorbs moisture and harbors mold. Sealing the exterior without addressing wet insulation traps the problem inside. We inspect and replace saturated sections as part of the sealing process.
- Corroded air handler cabinets. The blower motor compartment in Cloverleaf homes often shows the worst corrosion because condensate collects there and humid, chemically laden air accelerates rust. Sealing ducts without addressing the air handler leaves a major leak path and microbial reservoir untouched.
Pricing for Duct Sealing in Cloverleaf, TX
A typical whole-home duct sealing in Cloverleaf runs $850 – $1,200 for a single-story ranch under 2,000 square feet with accessible ductwork. Larger homes, multi-story layouts, or systems requiring significant rust remediation before sealing can run $1,400 – $1,800. Partial sealing of a single zone or repair section starts around $350 – $550.
What moves the price: accessibility of duct runs, amount of rust and debris removal required, whether sections of galvanized steel need replacement before sealing, and if the air handler cabinet requires separate treatment. We inspect first, write the price down, and get your approval before any work begins. No per-vent pricing. No teaser coupon that balloons once the van is in your driveway. One flat price per system, agreed in writing, and backed by the 365-Day Done Right Promise.
Call (361) 326-5060 for a free estimate. We’ll scope your system and give you the exact number.
We Also Serve Cities Near Cloverleaf
Our crews work throughout the region, and we regularly dispatch to Cloverleaf from our Houston office. We also serve Houston, San Antonio, Dallas, and Fort Worth with the same written pricing, uniformed technicians, and 365-Day Done Right Promise. Each location operates independently under The Garrison Standard, so the crew that arrives knows your local housing stock and climate conditions.
Serving Cloverleaf, TX - Our Local Coverage Area
We’re based in the Cloverleaf area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About Duct Sealing in Cloverleaf
The musty smell comes from humid Gulf Coast air entering your duct system through pinhole leaks and saturating the insulation or rust debris inside. In Cloverleaf, where many homes have original 1970s galvanized steel ductwork on slab foundations, that moisture has nowhere to drain and sits in the metal channels until the next heating or cooling cycle pushes the odor through your vents. Sealing the leaks stops the moisture intrusion at its source; a fogging sanitizer only masks the smell for a few days. Call (361) 326-5060 and we’ll camera-inspect to show you exactly where the air is getting in.
Yes, but only when the sealing addresses the actual leak paths that pull outside air into your system. The petrochemical corridor near Cloverleaf produces sulfur and volatile organic compounds that slip through pinhole leaks in corroded ductwork, especially when prevailing winds carry them toward residential areas. A proper mastic seal creates a pressure boundary that keeps those outside contaminants from entering your conditioned air. Fogging treatments cannot do this; they leave the leaks open. We include pressure testing to verify the seal holds against infiltration.
Most 1970s galvanized steel ductwork in Cloverleaf can be sealed if the corrosion is surface-level and the metal still has structural integrity. We camera-inspect first to distinguish pinhole leaks and rust flakes from sections where the metal has thinned to the point of collapse. If more than 30% of the run needs replacement, we’ll price that option in writing alongside the sealing estimate so you can compare. Many homeowners are surprised how much longer their original ducts last once properly sealed and protected from further moisture intrusion.
Duct cleaning removes debris, dust, and microbial growth from inside your duct runs. Duct sealing closes the physical gaps and leak paths that allow unconditioned air, moisture, and contaminants to enter in the first place. In Cloverleaf’s climate, you often need both: cleaning to remove what’s already growing in the humid environment, then sealing to stop new moisture and chemical-laden air from getting back in. We price each service separately and explain which your system actually needs before we start.
Signs that sealing is the primary need include uneven temperatures between rooms, energy bills that rose without rate increases, visible rust around vent registers, and musty odors that return within days or weeks after cleaning. If your system was cleaned recently and the smell came back, the leaks were never fixed. We offer free estimates in Cloverleaf that include a basic pressure test to measure air loss; if the number is above 15%, sealing will save you more money than another cleaning. Call (361) 326-5060 to schedule.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Cloverleaf and the greater Houston area since 2004.




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