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
Duct repair and sealing in Leesburg typically runs $340-$890 for most residential jobs, with flex duct repairs starting around $280 and full-system mastic sealing on large colonials reaching the upper end of that range. We dispatch crews to Leesburg from our Washington, DC coordination office, and most appointments are scheduled within a few business days. Call (240) 771-1508 for a written estimate before any work starts.
We know Leesburg’s housing stock intimately - the master-planned subdivisions north and east of downtown, the historic core along King Street, and everything in between. Our technicians have worked in Potomac Station, River Creek, Lansdowne, and the neighborhoods along Route 15 and the Dulles Greenway corridor. That local familiarity matters because Leesburg homes built during the 1990s and 2000s boom share specific ductwork vulnerabilities that a generic crew from outside the area simply won’t recognize.
Why CleanRun Air Duct Cleaning Ashburn Is Leesburg’s Preferred Duct Repair & Sealing Company
CleanRun has served the Leesburg market since 2013, and our reputation here is built on documentation, not promises. Every job arrives with a written price agreed before a single panel comes off, and every duct run is photographed before and after under our standard Documented Photo Record - a practice we’ve held since our first job. Haven Standard Clause 1 requires that written pricing; there’s no “call for a quote” in our process.
Our Leesburg customers consistently cite the photo record as the reason they chose us over competitors offering $79 coupons. They can see the 3-inch debris build-up at the first elbow, the torn flex liner dumping material into a sag, the failed mastic joint bleeding air into the attic. We don’t describe what we found; we show it.
Scheduling is coordinated from our Washington, DC office, with crews dispatched to Leesburg addresses across all ZIP codes including 20175, 20176, and 20177. Technicians are background-checked and uniformed under Haven Standard Clause 3: Verified Crews, and they’re identified by name before arrival.
The 365-Day Done Right Promise backs every Leesburg job in writing - if the repair or seal fails, we make it right. Not a policy subject to manager approval. A written guarantee, delivered with the job record.
Our Duct Repair & Sealing Services in Leesburg
Duct Sealing
Most Leesburg homes we work were built with mastic-sealed joints that have dried, cracked, or never fully adhered in the first place. Our sealing process starts with a pressure test to quantify air loss, then targets each failed joint with fresh mastic or mechanical sealant appropriate to the duct material. On two-story colonials in Potomac Station and River Creek, we commonly find the longest branch runs - the ones serving upstairs bedrooms - leaking 15-25% of their designed airflow at joints alone. We seal every accessible joint, then pressure-test again to verify the fix. The written scope and after-photos are delivered with the job record.
Flex Duct Repair
This is where Leesburg’s 1990s-2000s housing stock demands real expertise. Production builders of that era often installed flex duct with pronounced sags and kinks between joists, especially in the long runs to second-floor registers. Debris pools in those low spots. Worse, the inner liner degrades over time, and aggressive cleaning equipment can tear it if the technician doesn’t probe the run configuration first.
We were called to a two-story colonial in Potomac Station where the upstairs registers were blowing noticeably weaker than downstairs, and our camera inspection found a flex run sagging low between the joists with a torn inner liner dumping debris into the low spot. We probed the run configuration first, then sealed the failed joints with mastic and re-supported the sag so the branch could actually deliver air again. The homeowner mentioned the ducts had never been touched since the house was built.
Flex duct repair in Leesburg typically runs $280-$520 per run, depending on accessibility and whether full replacement of a damaged section is required.
Metal Duct Repair
The historic core near King Street and a handful of older neighborhoods contain homes with galvanized steel ductwork, sometimes original to mid-century renovations, sometimes retrofitted into 18th- and 19th-century framing in cramped, non-standard configurations. Metal duct repair here involves spot-welding or mechanical coupling of separated sections, replacement of rusted-out plenum connections, and resealing with high-temperature mastic. Access is often the challenge in these older Leesburg structures, and our estimates reflect actual time to reach the problem, not a flat rate that changes once we’re in the crawl space.
Duct Insulation
Leesburg’s humid summers and cold winter snaps make uninsulated or degraded duct insulation a real efficiency problem, particularly in attic and crawl space runs. We replace damaged insulation with foil-faced fiberglass or closed-cell foam wrap rated for HVAC applications, sealing the vapor barrier as we go. On homes near ongoing construction along the suburban fringe, where clay-rich dust infiltrates every opening, proper insulation also reduces the debris load hitting the duct interior.
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 professional-grade tools from Honeywell, Aprilaire, and Abatement Technologies - brands customers can look up independently before agreeing to a price. We stock common repair components for Leesburg’s dominant HVAC configurations, including flex duct couplings, mastic compounds, and register boots sized for the 6-inch and 8-inch branches typical in local production-built homes. That inventory means most Leesburg repairs are completed in a single visit, with no waiting on parts.
Common Duct Repair & Sealing Problems We See in Leesburg Homes
- Builder-era flex duct with sags and kinks - In Potomac Station, River Creek, and Lansdowne, we regularly find flex runs installed with pronounced low spots that pool construction dust and drywall debris. The joints at those low points leak first, because debris interferes with seal adhesion and the sag puts mechanical stress on the connection.
- Torn inner liners from uninformed cleaning - A technician who doesn’t camera-probe a sagging flex run before applying agitation tools can tear the inner liner, turning a maintenance visit into a repair job. We’ve fixed plenty of these in Leesburg, usually on homes that had a cheap coupon cleaning before calling us.
- Clay-rich construction dust coating duct interiors - Ongoing land development on Leesburg’s fringe kicks up fine, clay-heavy dust that neighboring homes pull through outdoor intakes. This dust masks failing mastic seals and accelerates liner degradation, so by the time owners notice weak airflow at the registers, multiple joints have already failed.
- Humidity-driven biological growth in supply plenums - Leesburg’s position on the Piedmont edge means humid summers with poor natural ventilation in attic-mounted systems. We find biological growth at plenum connections where cool air meets warm, moist attic air, compromising both air quality and seal integrity.
Pricing for Duct Repair & Sealing in Leesburg, VA
Most residential duct repair and sealing jobs in Leesburg fall between $340 and $890. Here’s how that breaks down:
- Single flex duct run repair: $280-$520
- Mastic sealing of accessible joints on a single-zone system: $340-$580
- Full-system mastic sealing on multi-zone colonial: $620-$890
- Duct insulation replacement (per run): $180-$340
- Metal duct repair (spot weld/coupling): $260-$480
What moves a job toward the higher end: multiple long branch runs, attic or crawl space access requiring additional time, discovery of additional failed joints during the initial scope, or homes with non-standard retrofit ductwork in the historic core. What doesn’t affect price: we don’t charge per vent, per register, or per linear foot. One flat price per system, agreed in writing before work starts, under Haven Standard Clause 1.
Bring us a competitor’s written estimate and we’ll provide a Free Second Opinion at no cost, with our number next to theirs.
We Also Serve Cities Near Leesburg
Our Duct Repair & Sealing crews work throughout Loudoun and Fairfax counties, including Leesburg neighbors Ashburn, Sterling, Herndon, and Chantilly. Each city gets the same documented process: written price first, photo record last, 365-Day Done Right Promise in between.
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
Start with a camera inspection that shows you what’s actually inside the ductwork, not a verbal summary. Because so much of Leesburg’s housing stock went up in the 1990s-2000s production-build boom, a huge share of local homes are only now getting their first-ever professional duct cleaning at the 20-to-25-year mark - so duct repair and sealing calls here often uncover decades of accumulated debris plus builder-era shortcuts in the same visit. We probe every flex run configuration before cleaning, document findings with photos, and deliver a written scope with pricing before any work begins. Call (240) 771-1508 to schedule - estimates are free.
Even homes built in the last few years on Leesburg’s developing fringe often contain significant construction debris in the ductwork. Drywall dust, wood particulate, and clay-rich site soil get pulled into the system during the build and remain there after handover. Builders rarely clean ducts before final walkthrough; they test the HVAC for function, not cleanliness. We’ve found 2-inch debris deposits in supply plenums of homes still under their builder warranty. The photo record shows exactly what the builder should have caught. Call (240) 771-1508 for an inspection - we’ll put our findings in writing.
Most sags can be repaired if the inner liner is intact or repairable - replacement is only necessary when the liner is torn through or the insulation is saturated. In Leesburg’s 1990s-2000s colonials, we re-support the sag with proper strapping, seal any failed joints with mastic, and verify airflow at the register before leaving. The key is probing the run configuration first, which cheap coupon operations often skip. A proper repair runs $280-$520 per run. Call (240) 771-1508 and we’ll camera the run before quoting.
Yes, directly. Leesburg’s position on the eastern edge of the Piedmont foothills, with the Blue Ridge hardwood forests immediately to the west, produces unusually heavy oak, cedar, and maple pollen loads that infiltrate return-air intakes each spring; the region’s humid summers then create interior moisture conditions that promote biological growth inside ductwork. That biological growth degrades mastic seals and accelerates flex liner deterioration, so repair work here often involves cleaning before sealing - and sealing with materials rated for high-humidity environments. Call (240) 771-1508 for a scope that addresses both.
A proper job starts with a pressure test to establish baseline air loss, then targets every accessible joint with fresh mastic or appropriate mechanical sealant. On Leesburg’s typical two-story colonial with upstairs and downstairs zones, we commonly find the longest branch runs - serving the master suite and secondary bedrooms - leaking 15-25% of designed airflow at joints alone. We seal, re-pressure-test to verify, and deliver before-and-after photos of every run. The written scope and photo record are included as standard deliverables, not extras. Typical cost for multi-zone sealing: $620-$890. Call (240) 771-1508 for a written estimate.
Ready to see what’s actually in your ductwork? Call (240) 771-1508 to schedule a free estimate. We’ll deliver a written price before any work starts, photograph every run before and after, and back the job with our 365-Day Done Right Promise - in writing, not as a footnote.
Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Leesburg since 2013.