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 Repair & Sealing Across Leesburg
Most Leesburg homeowners call us after they’ve already paid for a duct cleaning that didn’t fix the real problem. In a town where the dominant housing stock is 15-25 year old planned-community homes with original builder-grade flex ductwork, the failure mode is rarely surface debris. It’s liner degradation, attic heat damage, and sealed-in construction waste that a vacuum alone cannot address. Our Duct Repair & Sealing crew serves Leesburg from our Washington, DC dispatch office, and we typically schedule within 48-72 hours. Call (571) 520-6317 for a written estimate before any work starts.
Why CleanRun Air Duct Cleaning Herndon Is Leesburg’s Preferred Duct Repair & Sealing Company
We’ve been documenting the inside of Leesburg ductwork since 2013. That’s 52,000+ homes across the metro area, including hundreds in River Creek, Potomac Station, Lansdowne, and the historic downtown core. Every job starts with a written price under Haven Standard Clause 1 and ends with a photo record of every duct run.
Our technicians are background-checked, uniformed, and identified by name before arrival. Haven Standard Clause 3: Verified Crews means you know who’s walking in before the truck turns onto your street. We publish our license number on every page because a credential you have to hunt for is a credential that doesn’t exist.
Leesburg customers receive the same documented deliverable as every other CleanRun job: before-and-after photos of every duct run, a written scope of work, and the 365-Day Done Right Promise in writing. If it’s not right, we make it right. Not a policy subject to manager approval. A written guarantee.
We also offer a Free Second Opinion on any written estimate. Bring us a competitor’s quote and we’ll put our number next to it, line by line, in writing.
Our Duct Repair & Sealing Services in Leesburg
Duct Sealing
Leesburg’s boom-era homes were built fast during Loudoun County’s data-center expansion, and the duct sealing was often the first corner cut. We find supply leaks in attic runs that have been dumping conditioned air into unconditioned space for two decades. Our sealing process uses mastic sealant (a fiber-reinforced paste that remains flexible after curing) applied to every joint, seam, and penetration, then pressure-tested to verify. In River Creek and Potomac Station homes with duct board trunks, sealing is only performed after liner inspection, because sealing over degraded fiberglass facing traps fibers in the airflow stream.
Flex Duct Repair
The flex duct installed in Leesburg homes from 1995 to 2012 was typically suspended in vented attics with minimal support strapping. After 15-25 years of Mid-Atlantic humidity and summer attic temperatures exceeding 140°F, that flex sags, kinks, and separates at collar connections. We replace failed sections with new insulated flex supported at 4-foot intervals, then seal every connection with mastic and mechanical fasteners. The camera shows the difference between a kinked run choking airflow and a properly supported replacement.
Metal Duct Repair
Pre-1960s homes in and around historic downtown Leesburg often have galvanized steel ductwork retrofitted into spaces never designed for forced air. These runs rust at seams, separate at transverse joints, and develop condensation-driven corrosion where uninsulated metal passes through masonry walls. We cut access panels where needed, repair or replace damaged sections, and apply external mastic sealant to restore pressure integrity. Non-standard routing means every downtown job requires field measurement, not catalog parts.
Mastic Sealant Application
Mastic is the standard of care for duct sealing in Leesburg’s climate, not duct tape (which fails in humid attics within months). We apply fiber-reinforced mastic with a brush or sprayer to all seams, joints, and penetrations, then allow full cure before pressure testing. For duct board trunks with intact liner, mastic seals the air leaks without disturbing the facing. For trunks with degraded liner, mastic is applied to new foil-backed insulation after source removal of the failed material.
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.
BeforeAfterTrusted Brands We Service in Leesburg
Our equipment roster includes Rotobrush agitation systems, Nikro HEPA-filtered negative-pressure extractors, and Honeywell air quality monitors used to verify post-repair performance. We stock common flex duct diameters, collar connectors, and mastic compounds for Leesburg jobs, which means most repairs are completed in a single visit without waiting on parts. Every tool and material is named on your written scope so you can verify specifications independently.
Common Duct Repair & Sealing Problems We See in Leesburg Homes
- Builder-grade flex duct sagging and kinking in vented attics. In Lansdowne and River Creek, we regularly find flex runs that have dropped from their supports, creating sharp bends that reduce airflow by 30% or more. The camera reveals what a homeowner cannot see from the register.
- Duct board trunk lines shedding interior fiberglass facing. After 15-20 seasons in Leesburg’s attic heat and humidity, the interior surface of duct board trunks delaminates. Cleaning without sealing leaves glass fibers circulating; sealing without inspection traps them. Both must be addressed together.
- Construction debris sealed into new homes. Leesburg’s rapid growth produced homes where drywall dust, wood scraps, and insulation fragments were left in ducts at handover. The builder’s rough clean is not a finished clean, and the first professional inspection often reveals material that has been baked onto duct surfaces through two heating seasons.
- Non-standard retrofitted ductwork in pre-1960s downtown homes. Historic Leesburg properties with forced-air retrofits often have runs that violate modern design standards, tight turns with no access, and connections that can only be reached by cutting in panels.
Pricing for Duct Repair & Sealing in Leesburg, VA
A typical duct sealing job for a single-zone system in Leesburg runs $850-$1,400. Flex duct repair, including replacement of failed sections with new insulated flex and proper support, typically falls between $650-$1,100 per run. Metal duct repair in downtown Leesburg’s older homes, where access is limited and custom fabrication may be required, ranges from $1,200-$2,400 depending on linear footage and panel cuts. Mastic sealant application as a standalone service for intact systems with minor leakage starts at $450-$750.
These are whole-system prices agreed in writing before work starts. We do not quote per-vent or per-register pricing, and we do not offer teaser coupon rates that expand once the truck is on your driveway. Every estimate is free, every price is flat per system, and every job includes the documented photo record. Call (571) 520-6317 for your written estimate.
We Also Serve Cities Near Leesburg
Our crews work throughout Loudoun and Fairfax Counties, including Leesburg, Ashburn, Sterling, Herndon, and Chantilly. Scheduling and dispatch are coordinated from our Washington, DC office, with local crews serving each community.
Serving Leesburg, VA - Our Local Coverage Area
We’re based in the Leesburg 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 Leesburg
Because the builder’s rough clean is not a finished clean. In Leesburg’s fast-built boom-era subdivisions, drywall dust, wood scraps, and insulation fragments are commonly left in ducts at handover and then baked onto surfaces through the first heating season. We recommend a camera inspection at the 12-18 month mark, before the debris becomes adhered and harder to remove. Call (571) 520-6317 for a free inspection estimate.
The builder should have installed proper support strapping at 4-foot intervals for all flex runs, sealed every joint with mastic rather than tape, and performed a post-construction rough clean followed by a camera-verified finished clean before occupancy. Most did not. The result is sagging flex, leaky seams, and construction debris that our crews find in homes built as recently as 2012. We document what we find and provide a written scope to restore what the builder left unfinished.
The signs are visible on a camera inspection: fuzzy or flaky material on duct interior surfaces, increased dust accumulation at registers that returns quickly after cleaning, or irritation symptoms that correlate with HVAC runtime. In Potomac Station, our crew opened a return trunk feeding a second-floor air handler and found the interior fiberglass facing had delaminated into the airflow, coating the blower motor and downstream flex runs with glass fibers. We performed source removal with HEPA filtration and agitation tools under negative pressure, then rebuilt the failed trunk sections with mastic sealant and foil-backed insulation. A post-job camera inspection confirmed the supply and return ducts were sealed and the MERV rating at the filter was finally doing its job instead of catching shed liner. If you suspect liner degradation, call (571) 520-6317 for a camera inspection.
Yes, because the primary failure mode in pre-1960s downtown homes is pressure loss and contamination through leaky retrofitted metal ductwork, not surface debris accumulation. These homes were not designed for forced air, and the non-standard routing creates hard-to-access leaks that waste energy and draw in crawlspace or wall-cavity air. Sealing restores pressure integrity; cleaning without sealing is temporary at best. We cut access panels where needed, apply external mastic, and verify with pressure testing.
Leesburg sits at the eastern base of the Blue Ridge foothills, which funnels pollen from surrounding horse farms, vineyards, and forested slopes into the town at higher concentrations than the flatlands. The region’s reliably humid summers drive condensation risk in duct runs through unconditioned attics, the dominant construction pattern in boom-era neighborhoods. And the 15-25 year old housing stock is now hitting the age where original builder-grade materials fail predictably, especially duct board liner and unsupported flex. These three factors, specific to Leesburg’s geography and construction history, make duct repair a liner-inspection job first, not a cleaning job. Call (571) 520-6317 for an assessment written to your home’s actual condition.
Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Leesburg since 2013.