Whole-home duct cleaning
Dryer vent cleaning
Camera inspection
Sanitizing & deodorizingWhole-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 South Miami
Duct sealing in South Miami typically runs $450 – $1,200 per system, depending on how much of the ductwork is accessible and whether we’re sealing metal, fiberglass ductboard, or flex runs. Most jobs take four to eight hours and we schedule within a week of your call. If you’re losing cooled air into a hot attic or dealing with rooms that never reach the thermostat setting, the ducts are usually the culprit. Call (850) 660-3272 and we’ll inspect the system, write the price down, and seal it by the book.
We’re part of the South Miami community’s service network, and our crews know this housing stock. Mid-century ranches off Sunset Drive, low-rise condos near Dante Fascell Park, the original subdivisions along Red Road – we’ve worked in them all. Ducts in these homes behave differently than newer construction. They leak more. They collect more. And they need a specific approach, not a generic seal-and-go.
Why Hollis Air Duct Miami Is South Miami’s Preferred Duct Sealing Company
We operate under The Garrison Standard, which means every job gets a written price before we touch anything, a written guarantee, and a crew that arrives inside the quoted window in uniform. Our Duct Sealing team has been doing this work since 2004, and Roy Castellanos runs the operation with one rule: document what you do and stand behind it for a full year.
What does that mean for a South Miami homeowner? If a sealed joint fails within 365 days, we return and fix it at no charge. That’s the 365-Day Done Right Promise, and it’s in writing on every invoice. No vague “satisfaction guaranteed” language. No chasing a warranty department. You call, we schedule, we show up.
Phones are answered by a live person 24/7. Our technicians are background-checked and uniformed. And we use professional-grade equipment – Rotobrush systems, Nikro negative-air machines, and filtration from Honeywell and Guardsman – the same tools commercial crews run, not hardware-store gear.
Styles & brands we work with
Duct Repair in South Miami
Duct Repair in South Miami is a different animal than in drier markets because our attics run hot and wet for nine months of the year. A disconnected joint or a crushed flex run doesn’t just waste air; it pulls attic humidity into the system every time the blower kicks on. That means the repair isn’t complete until the section is reconnected, sealed, and insulation is checked around it.
Typical duct repair in South Miami runs $200 – $600 for a localized fix – say, a separated elbow above the air handler or a crushed return in a tight chase. More extensive repairs – multiple disconnected runs, collapsed flex, or damaged ductboard in a low-pitch attic – land closer to $700 – $1,500. We provide the range before we start, and it doesn’t move at the door.
Collapsed and Crushed Runs
In South Miami’s low-slung ranch homes, attic clearances are tight. Technicians from previous trade visits – cable installers, pest control, handymen – often crawl over flex ducts and crush them flat. We repair or replace the damaged section, then seal both ends with mastic so the repair doesn’t become a leak point.
Disconnected Joints Over the Air Handler
Vibration from the blower and years of thermal expansion loosen duct connections, especially on metal-to-flex transitions. The first sign is usually a warm closet or a hissing sound when the AC runs. We reconnect, seal with UL-approved mastic, and verify airflow with a static pressure reading before we call the job done.
Air Duct Sealing in South Miami
Air Duct Sealing in South Miami starts with finding every leak, not just the ones you can see from the attic hatch. That’s the information-gain difference: a generic crew seals the visible spots and misses the joints buried under insulation where condensation drips back into the fiberglass. We inspect the full run – supply and return – then seal it properly.
For a typical single-system home in South Miami, whole-system duct sealing runs $450 – $900. A larger home with three systems – common off Red Road and in the older Sunset Drive subdivisions – lands between $1,200 and $2,800 because each system gets its own inspection, sealing, and before-and-after airflow documentation. That’s per-system pricing, agreed before work begins.
Mastic Sealing for Metal Ducts
Older South Miami homes with original metal ductwork need mastic, not tape. Mastic is a brush-on sealant that hardens into a flexible, airtight skin. It handles the temperature swings in a hot attic without drying out or peeling the way tape does.
Aerosol Sealing for Ductboard and Flex
When ductwork is buried or hard to reach – common in low-pitch South Miami attics – we use aerosol sealant injected under pressure. The mist finds the leaks and bonds to the edges. It’s the same approach commercial HVAC crews use for hard-to-access runs, and it works well on fiberglass ductboard and older flex duct.
Trusted Brands We Service in South Miami
South Miami homes run a mix of duct materials and system brands, and we stock parts for most of them. Our crews work on metal, fiberglass ductboard, and flex installations, and our sealing materials meet the spec for units paired with Honeywell filtration and Guardsman media cabinets. We also use Rotobrush and Nikro equipment for our Dryer Vent Cleaning in South Miami and inspection work that often precedes sealing. If you need a specific brand serviced, call and ask – if we don’t have the part on the truck, we’ll source it locally and schedule a single return trip, not three.
Common Duct Sealing Problems We See in South Miami Homes
- Sealing only the visible sections. In South Miami’s low-pitch attics, the worst leaks are usually buried under insulation at the far end of a run. Sealing just the exposed joints leaves the system losing air where it matters most – and leaves condensation dripping back into the insulation.
- Using duct tape instead of mastic. Duct tape fails within a season under South Miami’s attic heat and humidity. The adhesive dries, the tape peels, and the leak returns. Proper mastic or UL-approved foil tape is the only repair that holds.
- Ignoring the undersized return air system. Many 1950s – 80s South Miami homes have return ducts too small for modern AC units. Sealing the supply side only increases static pressure and strains the blower motor. The return needs to be evaluated, too – sometimes enlarged, always sealed.
- Disturbing asbestos tape on original metal ducts. In neighborhoods just east of US-1 near Dante Fascell Park, older homes often have original metal ductwork with asbestos tape on the joints. That tape must not be scraped or sanded during sealing. We follow the proper containment protocol and seal over it without disrupting the fibers.
Pricing for Duct Sealing in South Miami, FL
A single-system duct sealing job in South Miami typically runs $450 – $900 for a standard ranch or condo. Two-system homes run $800 – $1,600. Three-system homes – common in the larger mid-century builds along Red Road and Sunset Drive – fall between $1,200 and $2,800. What moves the number? Attic accessibility, duct material, and how much of the run is buried under insulation.
We don’t quote per-vent. We don’t run a teaser price and add on once the truck is in the driveway. The price is written down, it covers the entire system, and it doesn’t change unless you add work. Call (850) 660-3272 for a free estimate – we’ll give you a real number before we schedule.
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AfterWe Also Serve Cities Near South Miami
Our crews cover South Miami and the surrounding metro, including Duct Sealing in South Miami and the nearby communities of Miami, Miami Beach, Miami Gardens, and Doral. Scheduling is coordinated from our Miami-area office, and we dispatch locally to keep drive times short and appointments on time.
Serving South Miami, FL - Our Local Coverage Area
We’re based in the South Miami 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 South Miami
Yes, if your home is east of US-1 near Dante Fascell Park or in any 1950s – 70s build with original metal ducts, the joints may have asbestos tape. We don’t scrape it or sand it. We seal over it using a containment protocol that keeps the fibers in place and the system airtight. If you suspect asbestos tape in your ducts, tell us when you call so we can plan the job correctly.
South Miami’s nine-month humid season means ducts are under constant moisture load. A leak that would waste 15% of your air in a dry climate also pulls attic humidity into the system here, which feeds mold around the air handler and inside the duct lining. Sealing done right stops both the air loss and the moisture ingress. We verify with a static pressure reading, not a visual guess.
For real results, yes. A three-system South Miami home – common in the larger mid-century builds – needs each system sealed independently. Partial sealing on one system leaves the other two leaking, and the comfort problem persists in parts of the house. We price per system and document each one’s before-and-after readings so you see exactly what changed.
You should receive before-and-after static pressure readings, a written description of what was sealed and where, photos of the work if the ducts are accessible, and a copy of the 365-Day Done Right Promise in writing. If a crew can’t produce that documentation, ask why. You’re paying for work you can’t see, and the paper trail is what holds the job accountable. Call (850) 660-3272 and we’ll walk you through exactly what you’ll receive.
Often, yes. Uneven cooling in South Miami homes is frequently a duct problem – a leaky run starving one side of the house, or an undersized return choking the system. Sealing the full supply and return, and sometimes enlarging the return, restores balanced airflow. It doesn’t fix every airflow issue – sometimes the problem is the unit itself – but in our experience, duct leakage is the most common cause in this housing stock.
One Thing to Know Before You Hire Anyone in South Miami
In the neighborhoods just east of US-1 near Dante Fascell Park, many older South Miami homes still have original metal ductwork with asbestos tape on the joints. That single fact changes how the job should be done. A crew that scrapes the tape off to get a clean surface is sending fibers into your air and violating protocol. A crew that ignores those joints entirely isn’t sealing the system. We’ve seen both approaches from other companies, and neither one holds up. You want a contractor who knows what that tape is, knows not to disturb it, and seals over it correctly – and that knowledge doesn’t come from a generic training video. It comes from working these specific houses, in this specific humid climate, for years.
What a Real South Miami Duct Sealing Job Looks Like
We recently sealed a three-system duct layout in a mid-century ranch off Red Road. The original fiberglass ductboard in the hot attic had developed leaks at every joint, and the homeowner had been chasing comfort issues for two summers. After a camera inspection confirmed mold around the air handler, our crew used HEPA filtration and aerosol mastic to seal supply and return ducts, then documented before-and-after static pressure readings for the homeowner. The job took a day. The improvement showed in the numbers before she felt it in the rooms.
That’s the standard. Inspection first, documentation after, and a written price in between. No seal-and-go. No “trust me, it’s fixed.” Just numbers, photos, and a one-year guarantee in writing.
Call Hollis Air Duct Miami for Duct Sealing in South Miami
If your South Miami home has leaks you can’t see, rooms that won’t cool evenly, or ducts that haven’t been touched since the Eisenhower administration, call us. We’ll inspect the full system, explain what needs sealing and why, and put the price in writing before any work starts. Roy Castellanos and the team at Hollis Air Duct Miami run every job to The Garrison Code: arrive inside the window, price it before we touch it, do it by the book, leave the site clean. Call (850) 660-3272 for a free estimate.
Written by Roy Castellanos, Owner at Hollis Air Duct Miami, serving South Miami and surrounding communities.