Fast, Reliable Duct Repair & Sealing Across St. Petersburg
Most duct repair jobs in St. Petersburg run $180-$650 and are finished in a single visit, with our crew typically on-site within a few hours of your call. If your airflow has dropped, your energy bill has climbed, or you’re pulling dust every time the AC cycles, separated or deteriorated ductwork is the likely cause.
We’ve been sending trucks to St. Petersburg since 1984. Our technicians know the difference between a 1920s bungalow in Childs Park and a mid-century concrete-block home in Central Oak Park, because the ductwork fails differently in each. Salt air off Tampa Bay, attic heat that shreds flex duct, and the near-constant humidity that keeps systems running ten or eleven months a year - these aren’t abstract problems here. They’re what we fix Monday through Saturday, and what our on-call crew handles when your system quits on a Sunday night. Call (844) 685-6342 and you’ll reach a live person, not a voicemail tree.
Why Bellows Air Duct & Vent Co. Is St. Petersburg’s Preferred Duct Repair & Sealing Company
Ray Castillo built this company on the idea that a homeowner should never have to argue about whether a job was done right. That’s why our Duct Repair & Sealing team carries a 90-Day Done Right Promise on every repair - if something isn’t right, we return at no charge and no paperwork required. We’ve honored that promise for over 42 years.
St. Petersburg customers call us back because the price we quote on the phone is the price on the invoice. No bait coupons, no surprises at the door. Before we lift a tool, we run a camera through your ductwork and show you what we see. After we finish, we run it again. That visual record belongs to you.
Our technicians are background-checked, uniformed, and equipped with Rotobrush and Abatement Technologies gear - the same brands serious HVAC contractors specify for their own homes. Most repairs are completed in one visit. And when you call (844) 685-6342, a live person answers, 24 hours a day.
Our Duct Repair & Sealing Services in St. Petersburg
Flex Duct Repair
Flex duct is the weak link in most St. Petersburg attic systems. In neighborhoods like Childs Park and Central Oak Park, original flex runs from the 1970s and 1980s are well past their service life. The plastic liner turns brittle in attic heat that routinely exceeds 130°F, the fiberglass insulation sheds into the airstream, and the wire helix corrodes from salt-laden humidity. We remove deteriorated sections, install new insulated flex rated for Florida attic conditions, and secure every joint with mechanical fasteners before sealing. A typical flex duct repair in St. Petersburg runs $220-$480 depending on linear footage and attic accessibility.

Mastic Sealant Application
Metal duct seams that were sealed with tape twenty years ago have failed. Tape adhesive degrades; mastic doesn’t. We brush on professional-grade mastic - the same compound specified by Abatement Technologies for commercial installs - to every joint, seam, and penetration. In St. Petersburg’s older homes near 4th Avenue North, where metal trunks run through uninsulated attic space, this is often the difference between conditioned air reaching your rooms and cooling your attic instead. Mastic sealing of a standard residential system in St. Petersburg typically costs $280-$520.

Metal Duct Repair
Coastal humidity corrodes metal duct from the outside in. Homes near the water - anywhere the Gulf breeze reaches - show surface rust on galvanized trunks that eventually pinholes and leaks. We cut out corroded sections, fabricate replacement segments on-site, and weld or mechanically fasten before sealing. Where rust is extensive but the trunk geometry is sound, we may recommend internal epoxy lining as an alternative to full replacement. Metal duct repair in St. Petersburg generally runs $340-$650 depending on material gauge and access.

Duct Insulation
Uninsulated or poorly insulated ductwork in a St. Petersburg attic is like running cold water through a hot pipe - condensation forms, insulation gets wet, mold follows. We wrap repaired or new duct runs with R-8 insulation minimum, sealed at every seam with foil tape and mastic. In homes near Hoyt Park and the Grand Central corridor, where attics see the worst heat buildup, this upgrade often pays for itself in reduced runtime within two cooling seasons. Duct insulation work in St. Petersburg ranges from $180 for spot repair to $580 for full system wrapping.

What happens when you call
- 1
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 St. Petersburg
We stock parts and materials from Rotobrush, Abatement Technologies, Aprilaire, and Guardsman - brands that hold up in Florida’s punishing conditions. Our St. Petersburg warehouse keeps mastic compounds rated for 200°F+ attic exposure, R-8 flex duct with antimicrobial liners, and corrosion-resistant fasteners that won’t fail six months after installation. That local inventory means we don’t special-order your repair and make you wait. Most jobs start and finish the same day we arrive.
Common Duct Repair & Sealing Problems We See in St. Petersburg Homes
- Flex duct liner deterioration in superheated attics. In St. Petersburg’s older neighborhoods - Crescent Heights, Euclid-St. Paul, Disston Heights - retrofitted ductwork was routed through attics that hit 140°F in July and August. The plastic liner degrades, the fiberglass sheds, and homeowners breathe attic debris without knowing it.
- Salt-laden humidity corroding metal seams. Homes near 4th Avenue South and anywhere the Gulf breeze penetrates show accelerated metal duct corrosion. The seams pinhole slowly, so the leak is hidden until your electric bill jumps or a room stops cooling evenly.
- Flood-wicked moisture in floor-level return plenums. Near Crescent Lake and the Grand Central corridor, summer storm flooding wicks ground moisture into return plenums. Duct board rots from the bottom up, contaminating the entire system. We inspect these plenums before quoting any cleaning or repair scope.
- Mastic failure from thermal cycling. In uninsulated attics, daily expansion and contraction cracks mastic seals within a few years. Joints separate. Conditioned air escapes into the attic, and the system runs longer to compensate.
Pricing for Duct Repair & Sealing in St. Petersburg, FL
We’re transparent about numbers because we’ve seen what bait-and-switch pricing does to homeowners who just want their house comfortable again.
| Service | Typical Range in St. Petersburg |
|---|---|
| Single flex duct section repair/replacement | $220 - $480 |
| Mastic sealing (standard residential system) | $280 - $520 |
| Metal duct repair (section replacement) | $340 - $650 |
| Duct insulation (spot to full system) | $180 - $580 |
| Return plenum replacement (flood-damaged) | $450 - $890 |
| Full system evaluation with camera inspection | $89 - $149 (credited toward repair) |
What moves you within these ranges: attic accessibility (tight crawl vs. walkable), linear footage of damaged duct, whether we can reach the repair from inside or need roof/attic entry, and whether mold remediation is required before sealing. We show you the camera footage, explain what we found, and give you the exact price before we start. No exceptions. Mention this page for $50 off any repair over $250, or ask about our $89 Seasonal Tune-Up if you’re not sure whether repair is needed yet. Seniors and veterans receive a permanent 5% discount.
We Also Serve Cities Near St. Petersburg
Our trucks cover the full Pinellas Peninsula. We regularly repair ductwork in St. Petersburg and the surrounding communities of Gulfport, South Pasadena, Lealman, and West and East Lealman. Same crew, same equipment, same upfront pricing - whether you’re off 34th Street South or across the bridge in Gulfport.
Serving St. Petersburg, FL - Our Local Coverage Area
We’re based in the St. Petersburg 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 St. Petersburg
If the flex duct is original to a 1950s install, replacement is usually the better investment. The plastic liner has exceeded its design life by decades, and attic heat in St. Petersburg’s uninsulated spaces accelerates deterioration beyond what repair can reliably address. We can patch a single separated joint for $220-$340, but when multiple runs show brittle liner or exposed fiberglass, full replacement with modern antimicrobial-lined flex prevents repeated service calls. Call (844) 685-6342 for a free camera inspection and we’ll show you exactly what you’re working with.
Persistent musty odor after cleaning almost always means moisture is entering the system from an unsealed joint, corroded plenum, or flood-wicked return. St. Petersburg’s 70%+ year-round humidity keeps duct interiors damp enough for mold to recolonize within weeks if the source isn’t fixed. Cleaning removes the symptom; sealing or replacing the compromised component removes the cause. Our crew identifies the entry point with camera inspection before we quote. Call (844) 685-6342 - estimates are free, and we don’t clean what we can’t fix permanently.
We don’t seal until we’ve addressed the moisture source. In flood-prone St. Petersburg neighborhoods, we first inspect floor-level plenums for water damage and rot, replace compromised duct board, then elevate or waterproof the new installation where possible. Mastic application requires a dry surface to bond properly, so we schedule sealing after the space has dried and we’ve confirmed no active leak. This approach costs more upfront than a quick seal, but it lasts. Ask about our Free Second Opinion on Any Written Estimate if another company quoted you sealing without inspecting for moisture damage.
Surface rust alone doesn’t require replacement if the metal retains structural integrity and the interior isn’t flaking. We sand, treat, and seal exterior rust with epoxy coating; interior rust that has progressed to scale or pinholing means air is escaping and the section needs replacement. Homes within a few blocks of Tampa Bay or the Gulf see faster progression, so we recommend annual camera inspection for coastal St. Petersburg properties. A spot repair with corrosion treatment runs $280-$420; full section replacement is $450-$650.
We specify Abatement Technologies and Guardsman mastic compounds rated for 200°F continuous exposure and high-humidity curing - critical in St. Petersburg attics where standard hardware-store mastic fails within a season. For homes with active mold concerns, we also stock Aprilaire-compatible antimicrobial sealants. The brand matters less than the application: we brush mastic 2-3 inches past every joint edge, embed fiberglass mesh at stress points, and allow full cure time before pressurizing the system. Call (844) 685-6342 for specifics on what we’d use in your home.
Our crew recently repaired a supply trunk in a 1940s bungalow on 22nd Avenue North, where the original flex duct had separated from the metal plenum, pouring attic debris into the living room. We replaced four feet of deteriorated duct, sealed all joints with Rotobrush mastic, and insulated the run with R-8 wrap to prevent future collapse under the summer heat.
In St. Petersburg’s older concrete-block bungalows, ductwork often runs through uninsulated attics that hit 140°F+, causing mastic to crack and flex duct joints to separate within a few years - a failure mode almost nonexistent in shaded two-story homes elsewhere. This is why we always inspect attic routing before quoting, and why we specify materials rated for the actual conditions your ductwork faces, not the conditions it was supposed to face when originally installed.
Ready to stop cooling your attic and start cooling your home? Call (844) 685-6342 now. A live person will answer, schedule your free estimate at a time that works for you, and send a background-checked, uniformed technician who’ll show you the camera footage before quoting a single dollar. That’s how we’ve worked in St. Petersburg for over 42 years. It’s not changing now.
Written by Ray Castillo, Owner at Bellows Air Duct & Vent Co., serving St. Petersburg since 1984.