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

Trusted Duct Repair & Sealing for Marietta Homeowners

If you’re wondering how much Duct Repair & Sealing costs, Marietta homeowners typically pay $280-$780 for most residential jobs, with flex duct replacement running higher if the plenum (the main distribution box connected to your air handler) needs work. We complete most repairs in a single scheduled visit and provide a written price before any work begins. Call (470) 516-9337 for a free estimate with exact numbers for your system.

Call (470) 516-9337

Since 2013, CleanRun has served more than 52,000 homes across metro Atlanta, including many through Duct Repair & Sealing - Marietta, and we’ve documented every duct run we’ve touched with before-and-after photography. Marietta’s housing stock presents specific challenges: the clay-heavy soils of Cobb County shift seasonally, stressing flex duct in crawl spaces, while the humid subtropical climate accelerates mastic sealant degradation in attics that reach 140°F in July. We’ve replaced collapsed flex duct in Indian Hills homes built during the 2019-2021 construction rush and sealed metal duct seams in 1980s East Cobb ranch houses where original fiberglass tape has turned to powder. Our crews are background-checked, uniformed, and identified by name before arrival under Haven Standard Clause 3: Verified Crews. Every job carries our 365-Day Done Right Promise in writing, not as a verbal assurance.

What Our Duct Repair & Sealing Service Includes

Duct Sealing

Duct sealing closes the gaps and disconnected joints that leak conditioned air into your attic, crawl space, or wall cavities. In Marietta, we commonly find 15-30% air loss in systems we’ve never touched, which means you’re heating and cooling spaces you don’t occupy. We use mastic sealant (a thick, brush-applied paste that remains flexible for decades) or metal-backed tape rated for HVAC use, never standard cloth duct tape that fails within two years. Every sealed joint is pressure-tested before we leave, and the photo record shows you exactly which runs were treated.

Flex Duct Repair

Flex duct, the insulated flexible tubing common in post-1990 construction, collapses, tears, or separates at its connection collars. In Marietta’s newer subdivisions like Walton Ridge and The Park at West Cobb, we’ve found flex duct crushed by installers who used it as a footpath in attics, and in older homes near Marietta Square, we’ve replaced sections where rodents have chewed through the outer vapor barrier. We also provide our Duct Repair & Sealing in Smyrna for homeowners in nearby communities facing similar issues. Our crews carry replacement flex duct in R-6 and R-8 insulation values, matching or exceeding your existing specification, and we photograph the damage before touching anything so you see why replacement beats repair.

Metal Duct Repair

Metal duct, typically galvanized steel in homes built before 1990, corrodes at seams, separates at slip joints, and develops pinholes from condensation in unconditioned spaces. We’ve repaired metal trunk lines in Marietta’s historic districts where original ductwork has lasted 40+ years but needs sectional replacement or custom-fabricated transition pieces. Our technicians carry sheet metal tools to form custom fittings on-site rather than forcing mismatched stock parts, and every repair is sealed with mastic and mechanical fasteners, not tape alone.

Duct Insulation

Duct insulation wraps your ductwork to prevent thermal loss and condensation formation. In Marietta’s climate, where attic temperatures exceed 130°F for weeks each summer, uninsulated or degraded duct insulation costs you significantly in cooling efficiency. We install formaldehyde-free fiberglass insulation with a reinforced foil vapor barrier, secured with proper mechanical fasteners and sealed tape, not the sagging, taped-together wraps we find on too many existing systems. The photo record documents R-value and coverage area so you have a permanent record of what was installed.

Mastic Sealant

Mastic sealant is the professional standard for sealing duct joints and seams, applied with a brush or caulking gun to create a permanent, flexible bond. Unlike tape, which can peel or degrade, mastic remains effective for the life of the duct system when properly applied. We apply mastic to every accessible joint in your system, including the plenum connections and register boots (the metal boxes that transition from duct to your floor or ceiling vents), and we photograph the application so you can verify coverage. In Marietta’s high-humidity environment, we use mastic rated for wet locations, not the cheaper formulations some contractors substitute.

Air Leak Repair

Air leak repair addresses the specific points where your duct system loses conditioned air to unoccupied spaces. We locate leaks using a combination of visual inspection, pressure differential testing, and when necessary, theatrical fog (a non-toxic, water-based vapor that reveals airflow paths) to trace hidden escapes. In Marietta homes with finished basements or encapsulated crawl spaces, we’ve found leaks at poorly sealed return air pathways that pull musty air into your living space. Every leak we repair is documented in your photo record with a description of the repair method used.

Signs You Need Duct Repair & Sealing Right Now

• Uneven temperatures room to room. If your master bedroom stays 8°F warmer than your kitchen in July, or your downstairs office is frigid while upstairs rooms are comfortable, your duct system is likely leaking or blocked. We’ve traced these complaints in Marietta homes to disconnected flex duct in attics and crushed sections behind knee walls that the homeowner had no way to see.
• Dust that returns within days of cleaning. When ducts pull air from your attic or crawl space through leaks, they introduce fiberglass particles, soil, and insect debris that overwhelm your filter. If you’re changing standard 1-inch filters monthly and still seeing dust accumulation on horizontal surfaces, the source is likely downstream of your filter, in the duct system itself.
• Utility bills that spike without explanation. A duct system leaking 20% of its air can increase your heating and cooling costs by 30% or more, because your equipment runs longer to achieve thermostat setpoints. We’ve had Marietta homeowners show us bills that jumped $80-$140 in a single month, with duct leaks as the primary cause.
• Whistling, rattling, or whooshing sounds from vents. These noises indicate pressure imbalances, loose register boots, or duct sections that have separated from their collars. The whistling you hear is air escaping at high velocity through a gap that should be sealed, and it represents conditioned air you’re paying for but not using.
• Musty or chemical odors when the system runs. Leaks in return ductwork can pull odors from crawl spaces, garages, or wall cavities into your living air. In Marietta’s humid climate, we’ve found return leaks that draw air past wet crawl space insulation, producing a persistent mildew smell that no air freshener can mask.

Before

After

Our Duct Repair & Sealing Process - Step by Step

1. 1
   System inspection and photo documentation. We photograph every accessible duct run before touching anything, using a camera system that captures the condition of flex duct, metal seams, insulation, and connections. You see what we see before any work is proposed.
2. 2
   Written scope and price delivered. Based on the inspection, we prepare a written scope of work with line-item pricing under Haven Standard Clause 1: Upfront Written Pricing. No work begins until you have the complete price in writing and have approved it. This is not an estimate that changes; it is the price you will pay.
3. 3
   Targeted repair or replacement. Our crews perform only the work specified in the written scope, using professional-grade equipment including Nikro negative-pressure extraction systems and Honeywell testing instruments. We do not upsell additional services during the visit.
4. 4
   Pressure test and verification. After repairs, we test system static pressure and verify that sealed joints hold under operating conditions. For sealed systems, we measure airflow at registers to confirm that repairs restored design flow rates.
5. 5
   Final photo record and documentation. We photograph every repaired or replaced section, compile the before-and-after record, and deliver it to you as part of the standard job file. This documented photo record, included on every visit since our first job in 2013, is your permanent evidence of what was done.

How Much Does Duct Repair & Sealing Cost in Marietta?

Duct Repair & Sealing Near Marietta - Our Service Area

We schedule duct repair and sealing throughout Cobb County and adjacent markets, including Duct Repair & Sealing in Smyrna, Duct Repair & Sealing in Kennesaw, Sandy Springs, Woodstock, Roswell, Atlanta, Holly Springs, Alpharetta, Douglasville, Milton, and Decatur. Most Marietta appointments are available within 2-4 business days, with emergency scheduling for systems that are completely non-functional. Our technicians live in the metro area and know the local housing stock, from the 1960s ranch homes near Kennesaw Mountain to the new construction in West Cobb’s Brookstone subdivisions.

Frequently Asked Questions - Duct Repair & Sealing in Marietta

Schedule Your Duct Repair & Sealing Service in Marietta Today

Call (470) 516-9337 to schedule your free estimate. You’ll speak with a live person who can answer specific questions about your system, check availability for your area of Marietta, and dispatch a background-checked, uniformed technician under Haven Standard Clause 3. The written price arrives before any work begins, the photo record documents every duct run, and the 365-Day Done Right Promise backs it all in writing. No coupons, no surprises, no vacuum noise.

Written by Tomas Reyes, Owner at CleanRun Air Duct Cleaning Marietta, serving Marietta and metro Atlanta since 2013.