Duct Repair & Sealing in Cumming - Leakage Measured, Then Priced in Writing

Trusted Duct Repair & Sealing for Cumming Homeowners

Duct repair and sealing in Cumming typically costs $280-$890 depending on whether you’re addressing minor register leaks or full flex duct replacement in the attic. Most jobs we handle in Forsyth County homes built between 2015 and 2020 take three to six hours and are scheduled within a week of your call, not months out. Call (678) 693-5322 and we’ll put a written price in your hand before any work starts.

Call (678) 693-5322

We’ve been repairing ductwork in Cumming since 2013, and the pattern we see is consistent: new construction homes here were often fitted with flex duct that’s fine for the first five years, then starts sagging at the plenum connections once Georgia’s attic heat cycles harden the adhesive. In neighborhoods like Coal Mountain, Vickery Village, and the Polo Golf & Country Club area, we’ve documented the same failure modes across dozens of homes - crushed duct runs behind finished basement ceilings, tape that turned to powder, and supply boots pulling away from drywall. Every one of those jobs started with a written price, included before-and-after photos of every duct run we touched, and was backed by our 365-Day Done Right Promise in writing on the invoice.

Our crews are background-checked, uniformed, and identified by name before arrival under Haven Standard Clause 3: Verified Crews. We carry professional-grade equipment from Rotobrush, Nikro, and Abatement Technologies - brands you can look up before you agree to anything. And we do not operate on coupons or teaser rates. Haven Standard Clause 1 requires a written price before any work starts, every time, with no exceptions.

What Our Duct Repair & Sealing Service Includes

Duct Sealing

Duct sealing closes the gaps and seams in your supply and return ductwork where conditioned air leaks into attics, crawl spaces, or wall cavities - the spaces you pay to heat and cool but never live in. In Cumming, we typically find 15-30% air loss in homes where the original builder-grade tape has failed, which shows up as rooms that never reach temperature and utility bills that climb every summer - one reason homeowners ask about our Duct Repair & Sealing in Cumming. Our crew applies mastic sealant (a thick, brush-on compound that remains flexible) and mechanical fasteners at every joint, then verifies the seal with a pressure test so you have documented proof the leakage rate dropped.

Flex Duct Repair

Flex duct is the ribbed, insulated tubing that connects your main trunk line to individual room registers, and it’s the most common duct type in Cumming subdivisions built after 2010. We repair flex duct when the inner liner tears, the insulation gets waterlogged from roof leaks, or the wire helix kinks and restricts airflow - a problem we see frequently in attics where installers left too much slack and the duct sagged over time. Our replacement sections use R-8 insulated flex with metal sleeves at both ends, secured with UV-rated zip ties and mastic, not the foil tape that fails in Georgia’s attic temperatures.

Metal Duct Repair

Metal ductwork - galvanized steel rectangular trunk lines and round pipe - still runs through many Cumming homes built before the 2000s, especially in older neighborhoods near downtown and along Bethelview Road. We repair separated seams, rusted sections, and loose connections where the original sealant has hardened and cracked. When a section is too corroded to salvage, we fabricate replacement pieces on-site or source from Guardsman and other trade-recognized suppliers, then seal with mastic and fiberglass mesh for a repair that outlasts the original installation.

Duct Insulation

Duct insulation wraps around your metal or flex duct to prevent thermal loss - the reason your second floor feels like a sauna in July even when the thermostat reads 72 downstairs. In Cumming’s climate, where attic temperatures regularly hit 140°F in summer, uninsulated or degraded duct insulation can raise your delivered air temperature by 10-15 degrees before it reaches the register. We install R-8 or R-6 fiberglass insulation with a vapor barrier jacket, secured with metal bands at proper spacing so it won’t sag or tear when our crews aren’t around to fix it again.

Mastic Sealant

Mastic sealant is the brush-applied, fiber-reinforced compound that forms the actual airtight seal at duct joints - superior to foil tape, which degrades in heat and UV exposure. We apply mastic at every connection, collar, and boot in the system, then embed fiberglass mesh tape at high-stress joints for reinforcement. In Cumming homes where the original builder used tape only, we’ve measured leakage rates drop from 25% to under 5% after proper mastic application, with photos of every joint in your delivered job record.

Air Leak Repair

Air leak repair targets the unintended pathways where your conditioned air escapes - disconnected boots behind walls, penetrations where plumbing or electrical lines pass through ductwork, and return plenums pulling attic air directly into your system. We locate these leaks with smoke pencils, thermal imaging, and pressure diagnostics, then repair with sheet metal patches, mastic, and mechanical fasteners. In one Cumming home near Kelly Mill Road, we found a 12-inch return leak pulling 85°F attic air into the system; the homeowner’s upstairs had never cooled properly since move-in, and the fix took four hours with photos to prove it.

Brands We Service for Duct Repair & Sealing

We’ve worked on duct systems connected to every major HVAC brand installed in Forsyth County over the past twelve years. That includes hundreds of Honeywell and Aprilaire air handlers and zoning panels, where we’ve repaired supply duct connections that failed due to vibration and replaced flex runs crushed by improper filter installation. We stock compatible fittings and transition pieces for these systems, and our crews photograph the interface between your ductwork and equipment so you can see the condition of both in your delivered record.

Whether your home has a Carrier, Trane, Lennox, Rheem, Goodman, or any other make, we can help. The ductwork itself is largely brand-agnostic - it’s sized by CFM requirements and static pressure, not by the logo on the air handler. What matters is matching the repair to the original design intent, and our written scope specifies exactly what we’re doing and why before any panel comes off.

Before

After

Signs You Need Duct Repair & Sealing Right Now

• Uneven temperatures room to room. If your master bedroom runs 8 degrees warmer than the hallway thermostat in summer, or your basement never heats in winter, the likely cause is a supply duct leak or crushed flex run diverting air before it reaches the register. We’ve traced this exact symptom to disconnected boots in Cumming’s Windermere and Brannon Oak Farm subdivisions.
• Dust accumulation around registers. Dark streaking on the ceiling near supply vents means your return duct is leaking, pulling attic air loaded with fiberglass and particulate through gaps in the ceiling plane. The register becomes a vacuum point, and everything in your attic ends up on your living room floor.
• Utility bills climbing year over year with no rate change. When your HVAC runs longer to compensate for 20-30% air loss, your kilowatt hours and therms climb in direct proportion. One Cumming homeowner on Castleberry Road saw a $340 summer cooling bill drop to $220 after we sealed a compromised return plenum that was pulling 110°F attic air.
• HVAC system short-cycling or running constantly. A system that can’t reach setpoint because conditioned air is leaking into the attic will run until it overheats or freezes, then shut down on safety. The wear on your compressor and blower motor is accelerated, and the repair costs shift from ductwork to major equipment.
• Musty or chemical odors when the system runs. Leaky return ducts in vented crawl spaces or attics pull in rodent activity, mildew, and off-gassing from insulation. If your home smells like attic every time the blower kicks on, the air path is compromised and needs documented inspection with a camera.

Our Duct Repair & Sealing Process - Step by Step

1. 1
   Written estimate before any work starts. We inspect your accessible ductwork with a borescope camera, identify every leak point and damaged section, and deliver a written price with line-item scope. Haven Standard Clause 1: no work begins until you’ve approved the number in writing. This takes 45-60 minutes and costs nothing.
2. 2
   Documented photo record of existing conditions. Before we touch anything, we photograph the inside of every duct run we plan to repair or seal - the debris buildup, the disconnected joint, the crushed flex, the rusted metal. These images go into your job record and are delivered with your invoice.
3. 3
   Targeted repair and sealing. Our crew performs only the work specified in your written scope: mastic application at joints, flex duct replacement where kinked or torn, metal patching where corroded, insulation replacement where degraded. We use Rotobrush and Nikro equipment for cleaning access points before sealing, and Abatement Technologies HEPA containment if we’re working in your living space during the job.
4. 4
   Pressure test and verification. After sealing, we measure system static pressure and calculate leakage rate against the pre-repair baseline. In Cumming, we typically see total system leakage drop from 20-25% to under 5% after proper repair and sealing. The numbers go in your written record.
5. 5
   Final photo record and written warranty delivery. We photograph every completed repair - the sealed joint, the replaced flex run, the patched metal section - and compile your full before-and-after record. Your invoice includes the 365-Day Done Right Promise in writing, with specific terms, not a generic satisfaction claim.

How Much Does Duct Repair & Sealing Cost in Cumming?

Duct Repair & Sealing Near Cumming - Our Service Area

We schedule duct repair and sealing throughout Forsyth County and into neighboring Cherokee, Fulton, and Gwinnett counties. That includes Buford and Milton directly, plus Suwanee, Alpharetta, Johns Creek, Duluth, Roswell, Norcross, Lawrenceville, Holly Springs, and Canton. Typical scheduling runs 3-7 days from your call for standard repairs; we do not claim emergency same-day dispatch because ductwork repair is a scheduled, documented job, not a rush transaction. Crews depart from our Cumming base, so Forsyth County homes generally see the earliest availability.

Frequently Asked Questions - Duct Repair & Sealing in Cumming

Schedule Your Duct Repair & Sealing Service in Cumming Today

Call (678) 693-5322 to schedule your free estimate. A live person answers, 7 days a week. We’ll inspect your ductwork with a camera, show you what we found, and put a written price in your hand before any work starts. Every job includes a documented photo record of every duct run and our 365-Day Done Right Promise in writing. No coupons, no per-vent pricing, no surprises - just the work you agreed to, done the way we documented it, at the price we quoted.

Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Cumming since 2013.