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.
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AfterFast, Reliable Duct Sealing Across Olympia Heights
Olympia Heights homeowners know the morning routine: the AC kicks on, and that musty, wet-dog smell hits the vents before cool air ever reaches the living room. We’re Hollis Air Duct Cleaning, and we’ve been sealing ducts in the post-WWII ranches and low-pitched apartment buildings that make up this unincorporated Miami-Dade community since 2004. Our crews dispatch from our Miami office and carry the same Rotobrush and Nikro equipment commercial outfits use on hospitals and schools. When you call (361) 326-5060, a live person answers, 24 hours a day, and we’ll get you a written price before any work starts. No callbacks, no voicemail loops, no price that moves at the door.
Why Hollis Air Duct Cleaning Is Olympia Heights’s Preferred Duct Sealing Company
We’ve earned our reputation in Olympia Heights by treating the real problem, not the symptom. Most companies pitch duct sealing as an energy-saving upgrade; here, it’s a condensation-control repair first, because the 1950s concrete-block ranches west of the Palmetto Expressway have a specific failure pattern no generic checklist catches.
Our Duct Sealing in Olympia Heights crews arrive inside the quoted window, in uniform, background-checked and verifiable. Every job is priced in writing before we touch a tool, backed by our 365-Day Done Right Promise: if the seal fails, the moisture returns, or the morning smell comes back within a year, we return and make it right at no charge, including a free second visit. That’s The Garrison Standard, and it’s how we operate at every independently owned Hollis location.
Phones are answered by a live person around the clock. No waiting until Monday for a callback that never comes.
Air Duct Sealing in Olympia Heights
Air Duct Sealing in Olympia Heights means stopping the leak paths that let humid attic air infiltrate your supply and return runs, but it also means addressing the condensation that feeds mold inside those same ducts. The job starts with a camera inspection of the attic trunk line, boots, and plenum connections. We identify where mastic has cracked, where tape has failed, and where the original 1950s insulation has torn away from sweating metal. Then we seal with fresh mastic and reinforced tape, restore the vapor barrier, and verify with a pressure test.
When Sealing Becomes a Moisture Job
Because Olympia Heights’s original ductwork runs through unconditioned attics in a tropical monsoon climate, the ducts routinely drop below the dew point overnight. Sealing over wet metal without fixing the condensation source traps moisture inside; mold regrows, and the new seal fails within a season. Our Duct Sealing protocol includes checking for adequate attic ventilation and insulation contact before we seal.
The Blower Motor Test
We pull an amp draw on your air handler before and after sealing. Undersized 1950s duct runs already strain the blower; sealing a system that’s too small for modern airflow just raises static pressure and burns out the motor faster. If the numbers don’t support sealing alone, we tell you straight.
Duct Sealing Services in Olympia Heights
Duct Sealing Services in Olympia Heights from Hollis cover the full repair sequence: inspection, source removal of mold and bio-growth where present, mechanical sealing of joints and penetrations, vapor-barrier restoration, and post-work verification. We don’t quote per-vent or per-boot pricing; we price by the system, in writing, before work begins. A typical whole-system seal in this market runs $850 – $1,400 for a single-story ranch, and $1,200 – $1,900 for a two-story or split system with multiple air handlers. What moves the number is attic accessibility, the extent of mold remediation needed before sealing, and whether the original ductwork is salvageable or requires sectional replacement.
Boot and Plenum Focus
On a ranch off SW 40th Street in the grid west of the Palmetto Expressway, we opened up an attic whose supply and return ducts were soaked at every boot; the homeowner’s morning complaint was the classic musty ‘wet dog’ smell when the air handler kicked on. Our tech ran a camera inspection, found the original undersized duct runs sweating through torn insulation and leaking at the plenum connection, and pulled a blower motor amp draw showing the system straining. We sealed the boot leaks and plenum penetrations after source removal, restored the vapor barrier, and the morning odor complaint cleared.
What We Won’t Do
We don’t seal over wet ductwork. We don’t ignore undersized runs. And we don’t stop at the visible trunk line while leaving boot leaks untouched above your ceiling. Those shortcuts are why cheap sealing jobs fail in Olympia Heights’s humidity.
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 Olympia Heights
Our trucks stock sealing mastic, reinforced foil tape, and replacement insulation from Nikro, Honeywell, and Aprilaire, plus vapor-barrier materials from Abatement Technologies. These are the same brands commercial HVAC crews use on schools and medical facilities, not hardware-store consumables that peel off in attic heat. For Olympia Heights customers, that means no waiting on parts orders that stretch a one-day job into a week. We carry what the 1950s ranches here need: mastic rated for continuous 180°F attic exposure, foil tape with acrylic adhesive that won’t turn to goo in July humidity, and insulation wraps that restore the thermal boundary your original ductwork never had.
Common Duct Sealing Problems We See in Olympia Heights Homes
- Sealing over wet attic ductwork instead of fixing the condensation source first. The moisture stays trapped, mold regrows, and the mastic or tape fails within a season. We see this on nearly every callback from a low-bid competitor in the grid streets west of the Palmetto.
- Ignoring the undersized 1950s duct runs. Sealing a system that’s already too small for modern airflow just moves the problem, raising static pressure and stressing the blower motor until it burns out.
- Missing the boot leaks and register penetrations hidden above the ceiling. A sealing job that stops at the visible trunk line leaves the majority of the mold-feeding leak paths untouched in these low-pitched attic ranches.
- Using consumer-grade tape that fails in Olympia Heights’s attic heat. The summer attic temperature here exceeds 140°F; hardware-store duct tape degrades in months, not years.
Pricing for Duct Sealing in Olympia Heights, FL
Here’s what duct sealing actually costs in this market. A single-story concrete-block ranch with one air handler and accessible attic space typically runs $850 – $1,400. A two-story home, split system, or property with multiple air handlers runs $1,200 – $1,900. If your ducts need source removal of mold and bio-growth before sealing, add $400 – $800 depending on contamination extent. What moves the price: attic accessibility (tight crawl vs. walkable), the linear feet of ductwork, number of boots and penetrations, and whether sectional replacement is needed where original duct is corroded through.
We give one flat price per system, agreed in writing before we start. No per-vent pricing. No add-ons at the door. Call (361) 326-5060 for an exact quote; estimates are free, and we carry the equipment to start same visit if you approve the price.
We Also Serve Cities Near Olympia Heights
Hollis Air Duct Cleaning dispatches crews throughout South Florida and maintains full service coverage in 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. Wherever you are in our service footprint, the process stays consistent: live answer, written quote, work by the book, site left clean.
Serving Olympia Heights, FL - Our Local Coverage Area
We’re based in the Olympia Heights 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 Olympia Heights
That’s condensation in your attic ductwork feeding mold growth overnight. In Olympia Heights’s 1950s ranches, the ducts drop below the dew point while the AC cycles off, then the blower pushes that musty air through the vents first thing in the morning. Sealing the leak paths and restoring the vapor barrier stops the moisture source. Call (361) 326-5060 and we’ll camera-inspect to confirm.
Cleaning first, if there’s active mold. Sealing over bio-growth traps it inside and the problem returns within a season. We inspect with a camera and price both steps in writing before starting. Most Olympia Heights jobs need source removal plus sealing to solve the morning smell permanently.
It depends on condition. If the metal is intact and the runs are properly sized for your current air handler, sealing and vapor-barrier restoration is the right fix. If the duct is corroded through, collapsed, or undersized to the point that sealing would overwork the blower, we recommend sectional replacement and price both options in writing. We pull blower amp draw to make that call with real numbers, not guesses.
Every three to five years for maintenance, but sooner if you smell the morning musty odor or see visible mold at registers. The tropical monsoon climate here means condensation never fully stops, so bio-growth accelerates faster than in drier regions. If your home is one of the original 1950s ranches with unconditioned attic ducts, lean toward the shorter interval and pair cleaning with sealing to break the moisture cycle.
Some, but not dramatically. The bigger win in Olympia Heights is stopping the condensation that ruins air quality and destroys equipment. Sealed ducts with intact vapor barriers don’t sweat, don’t grow mold, and don’t force your blower to compensate for pressure losses. You’ll likely see modest efficiency improvement, but the real return is avoiding mold remediation and premature blower replacement. Call (361) 326-5060 for an exact quote; estimates are free.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Olympia Heights since 2004.