Trusted Duct Repair & Sealing for Miami Homeowners
Duct repair and sealing in Miami typically costs $275–$850 depending on the scope, with most residential jobs completed in a single visit. At Apex Air Duct Cleaning Service Miami, owner Michael Brown handles every repair personally using professional-grade Rotobrush and Nikro equipment — 11 years focused on this single trade, backed by 867 verified reviews at 4.9 stars. If your AC runs constantly but rooms stay unevenly cooled, or your energy bills have climbed without explanation, leaking ducts are the likely culprit, and we’re available to diagnose it today at (833) 628-3661.
Miami’s climate punishes ductwork harder than most markets. The combination of year-round humidity, salt-laden air from Biscayne Bay, and attic temperatures that regularly exceed 140°F in summer causes flex duct adhesive to degrade, metal seams to separate, and insulation to compress or tear. We’ve repaired duct systems in homes from Norland to Coconut Grove where the original installer used tape instead of mastic, or where rodents have compromised flex runs in crawl spaces. Our approach is straightforward: we find every leak, repair or replace damaged sections with materials rated for South Florida conditions, and seal the entire system so your conditioned air reaches the rooms you’re paying to cool.
What Our Duct Repair & Sealing Service Includes
Duct Sealing
Duct sealing closes the gaps, cracks, and disconnected joints that allow cooled air to escape into your attic, crawl space, or wall cavities. In Miami, we regularly find that 20–30% of conditioned air never reaches the living space — you’re paying to cool your attic. We use mastic sealant and specialized tape rated for high-humidity environments, applied after pressure-testing to locate every leak, not just the obvious ones.
Flex Duct Repair
Flex duct is common in Miami homes built from the 1980s forward, but the plastic inner liner degrades in our heat, and the fiberglass insulation sags when saturated with humidity. We replace collapsed, torn, or water-damaged flex runs with new R-6 or R-8 insulated duct rated for attic installation, supporting it properly to prevent kinking that restricts airflow. In older Pinecrest and Coral Gables homes, we’ve replaced entire flex duct systems that had become porous after 15+ years of thermal cycling.
Metal Duct Repair
Galvanized steel ductwork, found in many pre-1980 Miami homes and commercial buildings, develops rust at seams and joints where condensation collects. We cut out corroded sections, fabricate replacement pieces on-site, and seal with mastic rather than failing duct tape. For commercial clients in Downtown Miami and Wynwood, we’ve restored metal trunk lines that were leaking 40% of their airflow through pinhole corrosion and separated drive cleats.
Duct Insulation
Under-insulated or degraded duct insulation forces your AC to overcook because cooled air warms before reaching your vents. We install fresh fiberglass duct wrap or closed-cell foam insulation where appropriate, with vapor barriers facing the correct direction for our humid climate. In Miami Gardens and Scott Lake, we’ve seen 10°F temperature drops at the register simply from replacing compressed or moisture-logged insulation.
Mastic Sealant
Mastic is the only permanent sealing method we use — a thick, fiber-reinforced compound that remains flexible and adheres to metal, flex duct, and fiberglass board. Unlike foil tape that dries and peels in Miami’s heat within 2–3 years, properly applied mastic lasts the life of the duct system. We brush or trowel mastic into every seam, joint, and penetration, then verify with a pressure test before we leave.
Air Leak Repair
Air leaks occur at connections between duct sections, around register boots, and where ducts pass through unconditioned spaces. We pressurize the system, use smoke pencils and thermal imaging to pinpoint leaks invisible to the eye, then repair each one with appropriate materials. In Andover and surrounding areas, this methodical approach has reduced our customers’ cooling bills by 15–25% in homes where leaks were the primary efficiency problem.
What happens when you call
- 1
A real person answersNo phone trees — you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Brands We Service for Duct Repair & Sealing
We’ve serviced and repaired duct systems connected to every major HVAC brand installed in South Florida. Our experience with Honeywell extends to their whole-home dehumidification and zoning systems, where duct integrity directly affects performance — we’ve restored ductwork in Honeywell-zoned homes in Aventura and Sunny Isles where improper sealing had thrown off damper balance and room-to-room temperature control. For Rotobrush equipment users, we bring a technician’s understanding of how their rotary brush systems interact with existing duct conditions; we’ve cleaned and then sealed ducts in the same visit for customers whose Rotobrush cleaning revealed hidden separation at flex duct connections.
Our work with Nikro negative-pressure vacuum systems means we understand airflow dynamics at a granular level — we apply that same pressure-testing rigor to our repair work, verifying that sealed systems hold negative pressure without bleed. Whether your home has a Carrier, Trane, Lennox, Rheem, or any other make, the ductwork itself is brand-agnostic, and our 11 years of single-trade focus means we’ve seen and repaired the failure modes specific to Miami’s climate across every combination of equipment.
Signs You Need Duct Repair & Sealing Right Now
- Uneven cooling from room to room. If your master bedroom stays comfortable but the guest room feels like a sauna, or vice versa, conditioned air is escaping before it reaches the problematic register. We measure airflow at each vent to confirm and trace the leak to its source.
- Dust accumulation immediately after cleaning. When your home gets dusty again within days of thorough cleaning, your return duct may be pulling attic air through gaps — along with fiberglass particles, rodent droppings, and Miami’s perennial pollen load.
- Energy bills rising without rate increases or usage changes. A duct system leaking 25% of its air forces your AC to run longer cycles to achieve thermostat setpoint. We’ve had Miami customers see $80–$150 monthly reductions after sealing alone.
- Whistling or rushing air sounds from walls or ceilings. These noises indicate high-velocity air escaping through gaps — often at register boots or where flex duct has pulled off its collar. The sound is your system literally throwing money into the wall cavity.
- Hot spots in attic or crawl space near duct runs. If you can feel cooled air when you poke your head into the attic, your ducts are cooling the wrong space. In Miami’s climate, this also creates condensation risks that lead to mold and structural damage.
Our Duct Repair & Sealing Process — Step by Step
- 1
Visual and tactile inspection. Michael Brown examines accessible ductwork for obvious damage — collapsed flex, separated joints, degraded tape, compressed insulation, and rust on metal components. In Miami attics, we also check for water staining that indicates condensation from missing or wet insulation.
- 2
Pressure testing with airflow measurement. We seal all registers and pressurize the duct system, measuring static pressure and calculating total leakage against the conditioned floor area. This gives us a hard number: how much air you’re losing, and whether it exceeds the 10% threshold that Energy Star considers excessive.
- 3
Leak detection with smoke and thermal imaging. With the system pressurized, we use smoke pencils to find active leaks and a FLIR thermal camera to identify temperature anomalies that reveal hidden gaps. This technology lets us spot leaks behind drywall or in inaccessible soffits without destructive exploration.
- 4
Targeted repair and replacement. We repair what can be saved and replace what can’t — always with materials rated for Miami’s humidity and temperature extremes. Every joint receives mastic sealant; every new flex run gets proper support straps to prevent future sagging.
- 5
Post-repair verification and documentation. We re-test pressure and measure airflow at each register to confirm improvement. You’ll receive before-and-after leakage numbers, plus photos of completed work. From cleaning to repair to sanitizing — handled in one visit by the same technician.
How Much Does Duct Repair & Sealing Cost in Miami?
A typical duct sealing job in Miami runs $275–$550 for a single-system residential home with accessible attic ductwork. Flex duct replacement for 2–3 damaged runs adds $180–$340 depending on length and R-value. Metal duct repair, which requires fabrication and more labor, typically ranges $350–$650 per section. Full duct insulation replacement in a 2,000-square-foot home with attic trunk lines generally falls between $850–$1,400.
Several factors move the needle on your specific price. Accessibility is the big one — attics with limited clearance, flat roofs with no attic space at all (common in Mid-Century Modern homes around Miami Shores), or crawl spaces under raised foundations all add labor time. Extent of damage matters: a single disconnected flex run versus a system where every joint has dried tape and separated seams. System size affects material quantities — a 5-ton system with extensive trunk-and-branch ductwork simply has more linear feet to address than a 2.5-ton compact system.
To avoid overpaying, get a written estimate that specifies the scope: how many linear feet, what materials, and whether post-repair testing is included. Some Miami contractors quote a low price for “sealing” that covers only visible registers while ignoring attic leaks. Our free estimates itemize every repair, show you the pressure-test results, and include verification testing in the quoted price — no surprise add-ons after we’re in your attic. Call (833) 628-3661 for an exact quote; estimates are free and carry no obligation.
Duct Repair & Sealing Near Miami — Our Service Area
We work throughout Miami-Dade and into southern Broward, with typical response times of same-day to next-day for repair calls. Our regular service area includes Norland, Scott Lake, Andover, Miami Gardens, Carol City, Lake Lucerne, Golden Glades, Ives Estates, Lake Forest, West Park, Miramar, and North Miami Beach. Whether you’re in a 1950s ranch in Westchester with original metal ductwork or a newer build in Doral with flex duct showing its age, we arrive with the equipment and materials to complete most repairs in a single visit.
Serving Miami, FL — Our Local Coverage Area
We’re based in the 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.
Frequently Asked Questions — Duct Repair & Sealing in Miami
Duct repair and sealing is the process of fixing damaged or disconnected HVAC ductwork and closing air leaks to restore proper airflow and efficiency. It includes replacing torn flex duct, patching metal seams, reconnecting separated joints, and applying mastic sealant to prevent conditioned air from escaping into unconditioned spaces. At Apex Air Duct Cleaning Service Miami, we combine repair with pressure-testing to verify results — from cleaning to repair to sanitizing, handled in one visit by owner Michael Brown.
Most residential duct repair and sealing jobs in Miami take 3–5 hours from arrival to final testing. A simple sealing job with accessible attic ductwork might finish in 2.5 hours, while extensive flex duct replacement in a cramped crawl space can extend to a full day. We schedule with realistic timeframes and don’t rush the verification testing that confirms your system is truly sealed. Call (833) 628-3661 to discuss your specific situation.
Duct sealing in Miami typically costs $275–$550, flex duct repair adds $180–$340 per run, and metal duct repair runs $350–$650 per section depending on accessibility and fabrication needs. Full insulation replacement for an average home ranges $850–$1,400. Your exact price depends on system size, damage extent, and attic or crawl space accessibility — all itemized in our free, no-obligation estimate. Call (833) 628-3661 for an exact quote; estimates are free.
Yes — we’ve serviced duct systems connected to Honeywell, Aprilaire, and every other major HVAC and air quality brand installed in South Florida. While ductwork itself is brand-agnostic, our familiarity with Honeywell zoning systems and Aprilaire whole-home solutions means we understand how duct integrity affects their specialized performance. Whether you have these brands or any other make, we can repair and seal your ductwork to manufacturer specifications.
We prioritize repair calls for complete duct failures that have left your home without cooling — especially critical for elderly residents, infants, and anyone with respiratory conditions during Miami’s summer heat. Same-day availability is common, though we don’t fabricate specific response-time guarantees. If your AC is running but no air is reaching your vents, or you’ve found a collapsed duct dumping water into your ceiling, call (833) 628-3661 and we’ll get you scheduled as quickly as possible.
We stand behind our workmanship and return promptly to address any issue with our repairs. We don’t publish a specific warranty term because duct system performance depends partly on factors outside our control — your AC maintenance habits, filter changes, and whether the original system design was adequate for your home. What we do guarantee is that Michael Brown, the owner, personally oversees every repair and will return to make it right if our sealing doesn’t hold or a repaired section fails prematurely.
Clear a path to your attic access, HVAC closet, and crawl space if applicable — we bring extension ladders and protective gear, but need 3–4 feet of clear floor space to stage equipment. If you have pets, secure them away from work areas; our Rotobrush and Nikro equipment generates noise that can stress animals. Finally, gather any recent energy bills if you’ve noticed cost increases — they help us quantify the savings potential from sealing. Call (833) 628-3661 when you’re ready to schedule; estimates are free.
Schedule Your Duct Repair & Sealing Service in Miami Today
Leaking ducts don’t fix themselves — they get worse as vibration, humidity, and thermal cycling open new gaps. If your Miami home has uneven cooling, rising energy bills, or dust that returns faster than it should, call (833) 628-3661 for a free estimate with owner Michael Brown. We’ll pressure-test your system, show you exactly where the air is escaping, and repair it with the same professional-grade equipment and 11 years of single-trade focus that earned us 867 verified reviews at 4.9 stars. No obligation, no pressure — just an honest assessment from the technician who’ll actually do the work.
Written by Michael Brown, Owner at Apex Air Duct Cleaning Service Miami, serving Miami since 2013.