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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Before
AfterFast, Reliable Duct Repair & Sealing Across Rockville
Duct repair and sealing in Rockville typically costs $280-$650 for most residential jobs, with full-system metal duct restoration in older homes running $800-$1,400. We dispatch crews to Rockville from our Washington, DC coordination office, and most appointments are scheduled within 48 hours. Call (571) 487-7204 for a written estimate before any work begins.
We’ve worked inside duct systems from Twinbrook’s 1950s ramblers to the garden condos along MD-355. Rockville’s housing stock tells a consistent story: decades of use, original materials still in place, and repair needs that only become obvious once a camera goes inside. Our Duct Repair & Sealing team documents every run before touching a tool. You’ll see what we see.
Why CleanRun Air Duct Cleaning Leesburg Is Rockville’s Preferred Duct Repair & Sealing Company
CleanRun has served Montgomery County since 2013, completing over 52,000 jobs with a written price delivered before work starts every time. In Rockville specifically, our documented photo records have become a reference point for homeowners who want evidence, not assurances. One customer in Rockcrest told us she chose us because we were the only company that showed her the inside of her ducts before quoting a price.
Our technicians are background-checked, uniformed, and identified by name before arrival - Haven Standard Clause 3: Verified Crews. Scheduling is coordinated from our Washington, DC office, with crews serving Rockville neighborhoods including Twinbrook, Rockcrest, and the MD-355 corridor directly. Every job concludes with a Documented Photo Record of every duct run, included as standard.
The 365-Day Done Right Promise applies in writing on every Rockville job. If the work is not right, we make it right. This is not a policy subject to manager approval. It is a written guarantee.
Our Duct Repair & Sealing Services in Rockville
Duct Sealing
Unsealed plenum joints and boot connections leak 20-30% of conditioned air into unconditioned spaces. In Rockville’s crawl-space and slab-on-grade homes, that lost air carries humidity and pollen directly into the structure. We seal every joint with mastic sealant - a water-based, fiber-reinforced compound that remains flexible and is rated for residential duct applications. For a typical Rockville single-family home, duct sealing runs $280-$450.
Metal Duct Repair
Original 1950s sheet-metal trunk-and-branch systems in Twinbrook and Rockcrest require approaches that differ from flex-duct work. Separated seams, corroded elbows, and disconnected branch runs are common where DIY additions from the 1970s-80s intersect with original construction. Our crews use metal repair techniques - not flex-duct patches - to restore structural integrity. Metal duct repair in Rockville typically ranges $350-$650 depending on accessibility and extent of damage.
Flex Duct Repair
Flex duct retrofits, common in crawl-space additions and basement finishings throughout Rockville, crush easily and degrade where they contact framing or insulation. We replace damaged flex runs with properly supported, insulated sections sized to the original HVAC load calculation. Expect $180-$340 per run for standard flex duct repair in Rockville homes.
Duct Insulation & Mastic Sealant
Unconditioned duct runs in Rockville crawl spaces lose both heating and cooling efficiency while accumulating condensation. We apply mastic sealant to all joints, then install or replace external insulation where the original has compressed or degraded. Combined sealing and insulation work for a partial system typically runs $450-$800 in Rockville’s market.
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.
Before
AfterTrusted Brands We Service in Rockville
Our equipment roster includes Rotobrush mechanical cleaning systems, Abatement Technologies negative-pressure extractors, and Aprilaire air quality components - tools you can look up independently before agreeing to any price. We stock common repair materials locally for Rockville jobs, which means most metal duct repairs and sealing work is completed in a single visit without waiting on parts. For specialized components in older systems, our supply chain reaches Montgomery County distributors within 24 hours.
Common Duct Repair & Sealing Problems We See in Rockville Homes
- Disconnected branch runs behind DIY additions. In Twinbrook and surrounding neighborhoods, 1970s-80s room additions frequently left ductwork partially disconnected from the original trunk. Crawl-space moisture and spring pollen enter these openings directly, contaminating supply air. Our camera inspection locates the break before any repair begins.
- Shedding fiberglass lining in original 1950s systems. The internal fiberglass lining of Rockville’s octopus-style trunk-and-branch systems degrades over decades, packing the main plenum with debris that restricts airflow and circulates particulates. This requires negative-pressure extraction - pulling debris out under controlled suction - not brush cleaning that would further damage the lining.
- Unsealed plenum joints wasting conditioned air. Original construction in Rockcrest and similar subdivisions often left plenum connections unsealed or sealed with failing tape. In Rockville’s humid summers, these leaks pull warm, moist air into the system, raising indoor humidity and creating conditions for mold colonization in crawl-space runs.
- Crushed flex duct in retrofits. Flex duct installed in later renovations along the MD-355 corridor frequently lacks proper support, sagging or crushing where it passes through tight framing cavities. Reduced airflow strains the air handler and leaves rooms persistently uncomfortable despite the thermostat setting.
Pricing for Duct Repair & Sealing in Rockville, MD
We publish ranges because Haven Standard Clause 1 requires a written price before any work starts. Here is what duct repair and sealing costs in Rockville’s current market:
| Service | Typical Range |
|---|---|
| Duct sealing (mastic, partial system) | $280-$450 |
| Flex duct repair (per run) | $180-$340 |
| Metal duct repair (seams, reconnections) | $350-$650 |
| Full metal trunk restoration with sealing | $800-$1,400 |
| Duct insulation replacement (partial) | $320-$580 |
Final price depends on system accessibility, extent of damage found during camera inspection, and whether crawl-space or attic work is required. We deliver the written price after inspection but before any repair begins. Free estimates are available at (571) 487-7204.
We Also Serve Cities Near Rockville
Our crews work throughout Montgomery County, including Duct Repair & Sealing in Rockville and surrounding communities: Potomac, Gaithersburg, Montgomery Village, and Germantown. Scheduling and dispatch are coordinated from our Washington, DC office.
Serving Rockville, MD - Our Local Coverage Area
We’re based in the Rockville 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 Rockville
Twinbrook contains one of the largest concentrations of 1950s-60s Cape Cods and ramblers in Montgomery County, most with original sheet-metal ductwork that has never been professionally addressed. The octopus-style trunk-and-branch design, combined with decades of internal fiberglass lining degradation, creates failure modes - packed plenums, disconnected branches from later additions - that do not occur in newer flex-duct systems. These homes require metal duct repair techniques and negative-pressure extraction equipment, not the brush-and-vac approach used on modern construction. Call (571) 487-7204 for a camera inspection and written estimate.
Uneven heating or cooling between rooms, persistent dust despite filter changes, and musty odors when the system runs are the three most common indicators. In Rockville’s older homes, rooms added in the 1970s-80s that never reach comfortable temperature often trace back to a disconnected branch run behind a finished wall or in a crawl space. Higher-than-expected energy bills without thermostat changes also suggest conditioned air is leaking into unconditioned spaces. We confirm the location with camera inspection before quoting repair. Call (571) 487-7204 to schedule.
Rockville summers regularly hit 90°F with dew points above 70°F, creating ideal conditions for mold colonization inside ductwork. Unsealed joints in crawl-space runs pull warm, moist air directly into the system, where it condenses on cooler duct surfaces. Sealing these joints with mastic sealant is the primary defense - it stops moisture intrusion at the entry point rather than treating symptoms later. For homes with crawl-space ductwork, we prioritize sealing before peak humidity season. Call (571) 487-7204 for timing recommendations specific to your system.
In most cases, yes. Separated seams, small corrosion holes, and disconnected branch runs are repairable with metal duct repair techniques - patching, reconnection, and mastic sealing - when the main trunk retains structural integrity. Full replacement becomes necessary only when corrosion has compromised the trunk’s ability to maintain pressure or when multiple large sections require simultaneous repair. Our camera inspection determines which path applies before any price is written. Call (571) 487-7204 for an assessment.
For Rockville’s older housing stock, we recommend duct inspection every 3-5 years, with cleaning and sealing as findings warrant. Homes in Twinbrook and Rockcrest with original 1950s systems often benefit from more frequent evaluation due to accumulated debris and aging joint seals. Spring pollen season (April-June) loads duct interiors rapidly in Montgomery County; post-spring inspection identifies whether pollen buildup has reached levels requiring cleaning. Sealing is typically a one-time repair unless subsequent modifications disturb the ductwork. Call (571) 487-7204 to establish a schedule based on your home’s age and system type.
Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Rockville since 2013.