Fast, Reliable Duct Repair & Sealing Across Sunset
Duct repair and sealing in Sunset typically runs $180-$650 depending on whether we’re re-sealing register boots, repairing flex-duct runs, or insulating attic lines, and most jobs are completed in a single visit. If your 1970s or 1980s Sunset home still has its original flex-duct system, separated boots and moisture intrusion are almost certain - the question is how far the damage has spread. Call (844) 685-6342 for a free estimate; we’ll camera-inspect your system and show you exactly what needs fixing before any work begins.
We’ve been driving the Kendall corridor to Sunset since 1984, and we know the housing stock here inside out. The ranch homes along SW 72nd Street, the split-levels near Miller Drive, and the Florida Room additions tucked behind them all share the same vulnerability: original fiberglass flex-duct that was never designed to endure four decades of South Florida humidity without maintenance. Our Duct Repair & Sealing team doesn’t guess at what’s wrong. We run a camera through every line, document the damage, and seal it with mastic and mechanical fasteners that hold.
Why Bellows Air Duct & Vent Co. Is Sunset’s Preferred Duct Repair & Sealing Company
Forty-two years in this business means we’ve seen what happens when ductwork is patched instead of properly repaired. Sunset homeowners call us because we’ve built our name on returning to fix what others rushed through. Our 90-Day Done Right Promise is stamped on every job: if it’s not right, we come back at no charge, no paperwork, no arguing. That’s not marketing language - it’s how Ray Castillo has run Bellows since 1984.
Our technicians are background-checked, uniformed, and equipped with Rotobrush and Abatement Technologies gear. They answer to a live person at our office 24 hours a day, not a voicemail tree. When you call (844) 685-6342, someone picks up. We serve Sunset and the surrounding Kendall corridor regularly, so our response time to the 33173 ZIP is typically same-day or next-day for non-emergency calls, and we prioritize appointments for homeowners who’ve noticed musty odors, uneven cooling, or visible mold around their registers.
We don’t bait-and-switch. The price we quote on the phone is the price on the invoice, disclosed before we lift a single tool. That’s been our founding promise since day one.
Our Duct Repair & Sealing Services in Sunset
Duct Sealing
Sealing is the backbone of what we do in Sunset. The 1970s-1980s tract homes that dominate 33173 were built with fiberglass flex-duct and paper-faced insulation that degrades differently here than anywhere else in the country. Because Sunset sits on the western fringe of Miami-Dade, just miles from the Everglades, relative humidity stays in the 80-90% range even during the so-called dry season. Any gap in your ductwork pulls that moisture-laden air directly into the system.
We seal with mastic - a water-based, fiber-reinforced compound that remains flexible and won’t crack like tape. We apply it at every joint, boot connection, and duct extension, then mechanically fasten with sheet metal screws where the original connection has failed. Our crew pressure-tests after sealing to confirm we’ve eliminated the leaks that let attic air contaminate your living space.
Flex Duct Repair
Original flex-duct in Sunset homes was never meant to last forty-plus years. The plastic inner liner becomes brittle. The fiberglass insulation compresses and sheds particles. The wire helix corrodes. We’ve replaced entire runs in homes near Sunset Drive where the duct had collapsed in the attic, cutting airflow to back bedrooms by more than half.
Our flex-duct repair isn’t a patch job. We cut out damaged sections and splice in new R-6 or R-8 insulated flex-duct, secured with metal sleeves and double-sealed with mastic and nylon zip ties. On a Kendall Drive ranch in Sunset, our crew found a flex-duct boot that had completely pulled away from the ceiling register in the Florida Room addition. We re-sealed the boot with mastic and reinforced the connection with sheet metal screws, then tested the newly sealed line with a Rotobrush system to ensure no attic air leakage re-contaminated the ductwork.
Metal Duct Repair
The 1980s split-levels scattered through Sunset’s eastern blocks often have galvanized steel trunk lines with flex-duct branches. Metal ducts don’t degrade from humidity the way flex does, but they corrode at seams, separate at transverse joints, and suffer from failed sealant that was applied decades ago. We repair metal duct with slip joints, drive cleats, and fresh mastic sealant. Where corrosion has penetrated the metal, we fabricate replacement sections on-site or source pre-formed fittings to match your existing system.
Duct Insulation
Unconditioned attics in Sunset are brutal environments. Roof deck temperatures exceed 140°F in summer, and the humidity never quits. When insulation separates from ductwork or compresses to the point of uselessness, you get condensation on cold air lines, energy loss, and the perfect conditions for mold growth. We re-insulate with foil-faced fiberglass wrap or replace the duct entirely if the insulation has absorbed moisture and degraded. Every insulation job we do in Sunset is camera-verified before and after, so you see the improvement, not just take our word for it.
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 Sunset
We stock parts and specify equipment from the same brands serious HVAC contractors use: Rotobrush for duct cleaning and verification, Abatement Technologies for containment and air scrubbing, and Aprilaire for humidification and filtration upgrades. For Sunset homeowners, this means we don’t wait on special orders for common repairs. Our trucks carry mastic sealant, flex-duct in multiple diameters, metal fittings, and insulation wrap so most jobs finish in one visit. If your system needs a component we don’t stock, our supply house relationships in Miami-Dade typically turn it around next-day.
Common Duct Repair & Sealing Problems We See in Sunset Homes
- Original flex-duct boots separated from registers after decades of humidity cycling. The paper-faced insulation and plastic liner expand and contract with every cooling cycle, and the mastic or tape used in the 1970s and 1980s has long since failed. Loose boots pull in attic air loaded with mold spores and fiberglass particles. Simple vent cleaning won’t fix this - the boot must be re-sealed and mechanically fastened.
- DIY-grade duct extensions from retrofitted Florida Rooms leak at every connection. When homeowners or handymen added duct runs to screen enclosures or Florida Rooms, they often used consumer-grade tape and unsupported flex-duct that sags in the attic. These connections become chronic condensation and microbial-growth hotspots because they lack proper slope, support, and sealing.
- Continuous AC operation prevents any seasonal dry-out period. In Sunset, your cooling system runs essentially twelve months a year. Unlike drier Sun Belt markets where ducts get a break in winter, moisture that enters through minor leaks never evaporates. Mold colonization isn’t a seasonal risk here - it’s a year-round baseline condition that makes sealing urgency far higher.
- Evaporator coil condensate issues spread contamination through ductwork faster than in coastal ZIP codes. Sunset’s location on the Everglades drainage basin means higher ambient humidity than areas closer to Biscayne Bay’s moderating sea breezes. Any upstream moisture problem - a clogged condensate line, an overflowing pan, or a dirty coil - accelerates microbial growth throughout the entire duct system.
Pricing for Duct Repair & Sealing in Sunset, FL
We’re upfront about numbers because nobody likes surprises on the bill. Here’s what duct repair and sealing typically costs in the 33173 market:
- Register boot re-sealing (single boot): $180-$260
- Flex-duct repair/replacement (per run, up to 25 feet): $280-$450
- Metal duct seam repair or section replacement: $320-$550
- Full duct sealing with mastic (average 1,800 sq. ft. home): $1,200-$1,800
- Duct insulation replacement (per run): $240-$380
What moves you up or down within these ranges: accessibility (crawls and tight attics take longer), extent of contamination (mold remediation adds containment and air-scrubbing steps), and whether we’re working with original 1970s fittings that need custom fabrication. We apply our $50 Off Any Repair Over $250 to qualifying jobs, and we always offer a Free Second Opinion on Any Written Estimate if you’ve already been quoted by another contractor. Senior and veteran homeowners receive a permanent 5% discount. Call (844) 685-6342 for an exact quote - estimates are free, and we show you camera footage so you understand exactly what you’re paying for.
We Also Serve Cities Near Sunset
Our crews work the full Kendall corridor and surrounding communities, including Duct Repair & Sealing in Sunset proper plus Olympia Heights, Westwood Lake, Richmond Heights, and Kendale Lakes. If you’re in a neighboring ZIP and noticing the same symptoms - musty registers, uneven cooling, or rising energy bills - we cover your area too.
Serving Sunset, FL - Our Local Coverage Area
We’re based in the Sunset 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 - Duct Repair & Sealing in Sunset
The original fiberglass flex-duct and paper-faced insulation in your home expand and contract with every cooling cycle, and after forty-plus years of Sunset’s 80-90% humidity, the adhesive and tape used at installation has degraded beyond recovery. The plastic liner becomes brittle, the wire helix corrodes, and the boot simply pulls away from the register. We re-attach with mastic sealant and mechanical fasteners - sheet metal screws that hold the boot in place permanently, not just until the next humidity spike. Call (844) 685-6342 for a free inspection and exact quote.
Yes, almost always. Florida Room duct extensions in Sunset were typically added by homeowners or handymen using consumer-grade materials: unsupported flex-duct that sags in the attic, connections sealed with hardware-store tape that dries out in months, and no proper slope for condensation drainage. These runs become chronic leak points that pull humid attic air into your system and create microbial hotspots. We replace DIY extensions with properly supported, mastic-sealed runs that match the rest of your system. Call (844) 685-6342 for a free second opinion on any written estimate you’ve already received.
Most duct repair and sealing work in Sunset does not require a permit if we’re repairing existing systems within the original footprint of your home. If we’re adding new duct runs, modifying trunk lines, or altering the HVAC system’s capacity, Miami-Dade County may require permitting. We handle permit research and applications when needed, and we’ll tell you upfront if your specific job triggers that requirement - no surprises after we start. Call (844) 685-6342 to discuss your project.
Sunset’s position on the Everglades drainage basin keeps relative humidity persistently higher than coastal Miami-Dade ZIP codes that benefit from Biscayne Bay’s sea breezes. This means moisture intrusion through duct leaks never gets a natural dry-out period, mold colonizes faster, and sealants must be selected for constant high-moisture environments. We use mastic compounds formulated for tropical conditions, not standard products that crack or lose adhesion in sustained humidity. Our repair methods account for the fact that your ducts are wetter inside and out than systems just five miles east. Call (844) 685-6342 for an estimate tailored to Sunset’s specific conditions.
Yes. The galvanized steel trunk lines common in 1980s split-levels don’t suffer the same humidity degradation as flex-duct, but they do corrode at seams, separate at joints, and lose original sealant. We repair metal duct with slip joints, drive cleats, and fresh mastic, fabricating replacement sections when corrosion has penetrated the metal. Our camera inspection will show you whether your metal ducts are intact or need section replacement. Call (844) 685-6342 for a free camera inspection and upfront pricing.
Don’t let separated boots and leaking ductwork keep pumping mold-laden attic air through your Sunset home. Bellows Air Duct & Vent Co. has repaired and sealed ductwork in 33173 and the Kendall corridor for over 42 years. We’ll camera-inspect your system, show you exactly what’s wrong, quote one honest price before we start, and back our work with the 90-Day Done Right Promise in writing. Call (844) 685-6342 today for your free estimate.
Written by Ray Castillo, Owner at Bellows Air Duct & Vent Co., serving Sunset since 1984.