Duct Sealing in Coral Gables - Tested First, Written Price Second

Fast, Reliable Duct Sealing Across Coral Gables

Duct sealing in Coral Gables typically runs $1,200 – $2,800 for a whole-home system, with most jobs completed in one day. If your vents blow weak air, your upstairs rooms never cool, or your power bill climbs through the humid summer, you’re probably losing conditioned air through gaps in your ductwork.

Call (361) 326-5060

We’re Hollis Air Duct Cleaning, part of the Garrison Partners family, and we’ve been sealing ducts in Coral Gables since 2004. Our crews work from our Miami office and serve Coral Gables directly. We know the tile roofs, the low attics, and the strict building codes that make this city different from anywhere else in South Florida. When you call (361) 326-5060, a live person answers, day or night. We’ll give you a written price before any work starts, and every seal is backed by our 365-Day Done Right Promise.

Why Hollis Air Duct Cleaning Is Coral Gables’s Preferred Duct Sealing Company

Coral Gables homeowners don’t need another company that treats their city like generic Miami-Dade. They need technicians who understand that a 1926 Mediterranean Revival on Alhambra Circle has different duct access than a 1960s ranch near the Biltmore, and that the City’s historic-preservation office has real authority over what gets modified.

We’ve built our reputation here on showing up inside the quoted window, pricing in writing, and leaving the site clean. Our technicians are background-checked and uniformed. You know who’s coming before they arrive. If a seal fails within a year, we return and make it right at no charge, including a free second visit. That’s not a verbal promise; it’s written on every job.

Our Duct Sealing team carries professional-grade equipment from Rotobrush and Abatement Technologies, the same tools commercial crews use on hospitals and schools. We don’t send salespeople who pivot to upsells once they’re inside your home. We send tradespeople who seal ducts by the book.

Duct Insulation in Coral Gables

Duct Insulation in Coral Gables addresses a problem most homeowners don’t know they have: cold air warming up before it ever reaches the vent. In Coral Gables’s tropical monsoon climate, where attics under barrel-tile roofs can hit 140°F and humidity stays above 70% for months, uninsulated or poorly insulated ductwork bleeds energy and breeds condensation.

A typical Duct Insulation job in Coral Gables runs $900 – $2,200 depending on linear footage and access difficulty. Homes near Granada Boulevard or Coral Way with original 1920s-40s chases often need the most attention, since historic-preservation codes prevent replacing those runs entirely.

Condensation Control in Humid Attics

When cold supply air moves through a 130°F attic, the duct surface sweats. That moisture drips onto ceilings, stains plaster, and feeds mold. We wrap supply lines with formaldehyde-free fiberglass insulation and vapor-seal every seam with mastic, not tape that peels in humidity.

Preservation-Compliant Installation

Many Coral Gables homes cannot accept new duct chases without City approval. Our insulation work is designed to be reversible and non-invasive, documented with before-and-after photos so you have a record that satisfies both building inspectors and historic-preservation review if you ever sell.

HVAC Duct Sealing in Coral Gables

HVAC Duct Sealing in Coral Gables stops the conditioned air you’re already paying for from leaking into your attic, walls, or crawlspace before it reaches your rooms. In a city where air handlers run almost continuously eight months a year, even a 15% duct leakage rate can add hundreds to your annual power bill.

Typical HVAC Duct Sealing in Coral Gables costs $1,200 – $2,800 for a full system, with partial repairs on specific zones starting around $450. The price depends on access, the condition of existing metal, and whether we need to coordinate with a roofer for soffit entry on low-pitch tile roofs.

Pressure Testing and Leak Detection

We pressurize your duct system and measure airflow loss with a calibrated manometer. This gives us a hard number, not a guess. We mark every leak with a numbered flag, photograph it, and show you before we seal. You’ll know exactly what was wrong and what we fixed.

Mastic Sealing on Original Metal

Original galvanized duct in Coral Gables’s older homes flexes and expands with every HVAC cycle. Duct tape fails within months in this environment. We use water-based duct sealing mastic, brushed into every joint and boot, that remains flexible and adheres through decades of thermal cycling and humidity.

Trusted Brands We Service in Coral Gables

We stock parts and materials from Aprilaire, Abatement Technologies, and Guardsman, plus we carry Rotobrush agitation tools for jobs where biofilm buildup requires mechanical cleaning before sealing can adhere. For Coral Gables customers, this means no waiting on Miami warehouse delivery for standard fittings, boots, or plenum patches. We keep common sizes for Mediterranean Revival and mid-century ranch layouts on our trucks. If your system uses Honeywell or Aprilaire filtration components, we can inspect and reseat those connections as part of the sealing process. Turnaround matters in a climate where going without AC for even a day is not realistic.

Common Duct Sealing Problems We See in Coral Gables Homes

• Roof-soffit access on barrel-tile, low-pitch attics leaves connectors and plenum joints misaligned after sealing, so leaks persist at takeoffs despite new mastic. The tight geometry of these roofs means technicians often cannot square their bodies to apply sealant evenly. We use borescope cameras to verify coverage after the fact, not just visual inspection.
• Year-round humid biofilm from ficus and oak debris keeps joints and boots damp, causing sealant to lose adhesion and fail within one rainy season. On streets like Granada Boulevard under mature canopy, we treat biofilm with antimicrobial application before any sealant goes on. Skipping this step is why some Coral Gables homeowners need resealing every 18 months.
• Historic-preservation limits on chase modification force patchwork seals on 1920s-40s ducting, which can fail when original galvanized metal flexes during continuous HVAC operation. The City will not approve wholesale replacement of original chases in designated historic districts. Our patches use expansion-compatible materials rated for the flex cycle count we measure in these older systems.
• Hurricane-driven moisture intrusion saturates duct insulation and corrodes metal seams, creating new leaks that did not exist before the storm. After major storms, we inspect Coral Gables homes for water ingress at roof penetrations and soffit vents, then reseal any compromised joints before mold establishes.

Pricing for Duct Sealing in Coral Gables, FL

We Also Serve Cities Near Coral Gables

Our crews based in Miami serve Coral Gables directly, and we regularly travel to Miami, Key Biscayne, Miami Beach, and Hialeah for duct sealing and insulation work. Each job carries the same written price guarantee and 365-Day Done Right Promise, regardless of drive time.

FAQs About Duct Sealing in Coral Gables