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 Sweetwater
Most duct sealing crews in South Florida are trained for attic trunk-and-branch systems in site-built homes. That training misses the mark in Sweetwater, where the vast majority of residences are manufactured homes with underfloor, belly-board duct runs that haven’t been touched since the 1970s or 1980s. We’re the crew that knows to pull the belly board, not climb into a nonexistent attic. If your registers are blowing weak, your cooling bills are climbing, or you’re smelling musty air from below the floor, call (361) 326-5060. We dispatch to Sweetwater from our Miami office and schedule by the book, with a written price before any work starts and our 365-Day Done Right Promise on every job.
Why Hollis Air Duct Cleaning Is Sweetwater’s Preferred Duct Sealing Company
We’ve been doing this since 2004, and our Duct Sealing team has learned that Sweetwater’s manufactured-home market demands a completely different playbook than conventional suburban work. The Garrison Standard requires our technicians to arrive inside the quoted window, price every job in writing before touching equipment, and leave the site clean. That discipline matters here because too many outfits quote a low price for “duct cleaning,” run a rotary brush through the registers from above, and never address the real problem: disconnected, crushed, or unsealed flex runs sitting in damp crawlspace air beneath the home.
Our technicians are background-checked and uniformed. You’ll know who’s arriving before they pull up. Phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops, no callback queues. And every repair is covered by our 365-Day Done Right Promise: if the work 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 written on every job.
Air Duct Sealing in Sweetwater
Air Duct Sealing in Sweetwater means sealing underfloor flex-duct and low-profile panel systems from beneath the home, not from above. The manufactured homes that make up most of Sweetwater’s housing stock were built with at-grade ductwork that’s now fifty to sixty years old. Original flex runs sag, disconnect at collars, and lose insulation. The belly board, a membrane stretched under the floor, is supposed to protect these runs from crawlspace air and pests. When it fails, which it does, your HVAC system pulls in hot, humid, contaminated air from below and tries to cool it. Your bills spike. Your system runs constantly. And a crew that only knows attic work never finds the leak.
What We Find Under the Floor
On a double-wide off SW 4th Street, our tech pulled the belly board and found a crushed 1960s-era flex run feeding two bedroom registers, with the supply and return ducts disconnected at the collar and rodent-chewed insulation along the perimeter. We performed source removal with agitation tools under negative pressure and HEPA filtration, then sealed the run with mastic and mesh before re-insulating and closing the belly. The blower motor amp draw dropped and the homeowner’s cooling bills stopped running away from her. That’s the kind of fix that actually moves the needle in Sweetwater.
When Sealing Beats Replacement
Not every old flex run needs to come out. If the duct is intact but the seals have failed at the collar or the insulation is compromised, we can seal and re-insulate in place. That saves the homeowner the cost of full duct replacement, which in a manufactured home with limited access can run significantly higher. We price both options in writing before any work starts, so you know exactly what you’re paying for and why.
Duct Sealing Services in Sweetwater
Duct Sealing Services in Sweetwater cover the full range of underfloor ductwork found in the city’s manufactured housing stock: single-wide and double-wide units with belly-board-protected flex runs, low-profile panel systems in newer replacement homes, and the occasional site-built home with conventional attic ducts near the Dolphin Mall corridor or along Flagler Street. Our crews carry Rotobrush rotary brush systems and Nikro negative-air machines, but in Sweetwater the critical tools are often a good flashlight, mastic compound, mesh tape, and replacement insulation board. The work is physical. It’s done on your back in tight spaces. And it requires knowing what a failed belly board looks like before you quote the job.
The Garrison Code on Site
Our technicians operate under The Garrison Code: arrive inside the window, price in writing, complete the job by the book, leave the site clean. In Sweetwater, that means re-securing the belly board properly after sealing, not stapling it loosely and calling it done. A sloppy belly-board reseal invites rodents back in within months. We do it right because we have to come back if it fails, and we’d rather not.

Equipment That Matches the Job
We use professional-grade equipment from Rotobrush and Nikro, plus filtration products from Honeywell and Abatement Technologies. In Sweetwater’s underfloor environments, HEPA filtration matters because we’re working in spaces that may have mold spores, rodent debris, or standing water from the area’s flat, flood-prone terrain. We contain the work zone and filter the air we disturb. That’s standard on every job, not an upsell.

What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Sweetwater
We stock parts and materials from Honeywell, Abatement Technologies, and Guardsman for Sweetwater customers, which means faster turnaround on jobs that need replacement collars, insulation board, or filtration upgrades. Most manufactured-home duct components are standardized, but the combination of age, humidity damage, and non-standard retrofits we see in Sweetwater means we often need to adapt on site. Having the right materials in the van, not on order from a warehouse, lets us complete the job in one visit. That’s part of The Garrison Standard: show up prepared, finish what you started, and don’t leave a homeowner waiting on parts while their AC pulls crawlspace air through a half-sealed system.
Common Duct Sealing Problems We See in Sweetwater Homes
- Belly-board failures from rodent entry. The underfloor membrane is the number one source of contaminated duct air in Sweetwater’s mobile homes. Rodents chew through the belly board, nest in the insulation, and create entry points for damp crawlspace air that gets pulled straight into supply and return ducts.
- Disconnected collars on original flex runs. The 1960s through 1990s flex duct in most Sweetwater manufactured homes sags and pulls away from the air handler collar over decades of vibration and thermal cycling. Hot humid air from the crawlspace gets drawn in, condensates inside the duct, and breeds mold.
- Crushed or kinked flex runs from ground settling. Sweetwater’s flat, flood-prone terrain means underfloor spaces can stay damp for extended periods. Duct supports corrode or rot, letting heavy flex runs sag onto the ground, kink, or crush entirely. Airflow drops. System run time doubles.
- Insulation breakdown from constant condensation. South Florida’s year-round humidity and nonstop cooling season mean duct exteriors stay wet for months. Fiberglass insulation delaminates, loses R-value, and falls away, leaving bare metal or flex that sweats directly into the crawlspace and re-evaporates moisture into the home.
Pricing for Duct Sealing in Sweetwater, FL
A typical duct sealing job in Sweetwater runs $450 to $1,200 for a single-wide or double-wide manufactured home, depending on how many runs need attention, whether the belly board can be resealed or needs replacement, and the condition of the original insulation. Site-built homes with accessible attic ducts near the Dolphin Mall area or along Flagler typically fall in the $350 to $800 range because the access is straightforward and the materials are standard.
What moves the price: number of disconnected collars, extent of rodent damage requiring source removal before sealing, belly-board replacement versus repair, and whether we need to bring in negative-air HEPA containment for mold-affected areas. We do not quote per-vent pricing. We quote one flat price per system, agreed in writing before work starts. That price does not move at the door. Call (361) 326-5060 for a free estimate. We’ll inspect the underfloor system, show you what we found, and give you a written number you can count on.
We Also Serve Cities Near Sweetwater
Hollis Air Duct Cleaning dispatches crews throughout South and Central Florida. If you’re outside Sweetwater, we also provide Duct Sealing in Sweetwater and surrounding areas including Jacksonville, Miami, Tampa, and Orlando. Each location operates independently under The Garrison Standard with the same written pricing, background-checked technicians, and 365-Day Done Right Promise.
Serving Sweetwater, FL - Our Local Coverage Area
We’re based in the Sweetwater 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 Sweetwater
It costs more because the work happens in tight underfloor crawlspaces, not open attics. Most Sweetwater homes are manufactured units with belly-board duct systems that require pulling the membrane, working on your back, and resealing properly afterward. The labor is harder and slower, and the materials, mastic, mesh, insulation board, are specialized for damp underfloor environments. Call (361) 326-5060 for a written estimate on your specific home.
Yes, in most cases we access the ducts from beneath the home by pulling the belly board, not by cutting the interior floor. The belly board is designed to be removed and resecured. We seal the flex runs and collars from below, then reseal the membrane. The interior floor stays intact. Call (361) 326-5060 and we’ll confirm access for your specific unit.
It fixes the leaks that let unconditioned crawlspace air into your supply and return ducts: disconnected collars, crushed flex runs, failed belly-board seals, and degraded insulation. In Sweetwater’s 1960s through 1990s manufactured homes, these problems are nearly universal. Sealing them reduces blower motor strain, cuts cooling run time, and stops your system from pulling musty, humid air from below the floor. Call (361) 326-5060 to schedule an inspection.
If your registers blow weak or uneven air, your cooling bills have climbed without rate increases, or you smell musty air when the system runs, you likely have duct leaks that sealing will fix. If the ducts are intact but filled with dust and debris, cleaning comes first. We inspect the underfloor system and tell you which applies, with a written price for either option before any work starts. Call (361) 326-5060 for a free assessment.
Yes, it affects both the problem and the repair. Constant humidity keeps duct exteriors wet, which breaks down insulation and accelerates corrosion at supports and collars. When we seal ducts in Sweetwater, we use mastic rated for damp environments and replace degraded insulation with materials that resist moisture absorption. The belly-board reseal is critical because without it, humid crawlspace air continues to attack the repair. Call (361) 326-5060 to schedule work that holds up in local conditions.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Sweetwater since 2004.




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