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.
Fast, Reliable Duct Repair & Sealing Across Mount Prospect
Duct repair and sealing in Mount Prospect typically costs $280-$890 depending on whether we’re sealing accessible joints with mastic or rebuilding crushed flex runs in a crawl space. Most jobs are quoted same-day and completed in a single visit. Call (224) 344-8881 for a written estimate before any work starts.
We serve Mount Prospect from our Chicago office, with crews running daily routes through the northwest suburbs. You’ll know your technician’s name before arrival, and every visit ends with a documented photo record of what we found and what we fixed.
Why CleanRun Air Duct Cleaning Elk Grove Village Is Mount Prospect’s Preferred Duct Repair & Sealing Company
CleanRun has been independently owned and operated under the Haven Standard since 2013. We’ve documented the inside of over 52,000 homes, and Mount Prospect’s aging ranch and split-level stock presents some of the most consistent duct conditions we see anywhere in the metro area.
Our Mount Prospect customers leave reviews that specifically mention the photo record - being shown a disconnected branch behind drywall, or a plenum loaded with deteriorated fiberglass liner, before any repair is proposed. The 365-Day Done Right Promise is backed in writing on every job, not just stated in marketing copy. Haven Standard Clause 1 requires a written price before any work starts; there is no “call for a quote” in our process.
Dispatch and scheduling are coordinated from our Chicago office, and crews serving Mount Prospect carry professional-grade equipment from Rotobrush, Abatement Technologies, and Guardsman - brands you can verify independently before agreeing to any scope of work.
Our Duct Repair & Sealing Services in Mount Prospect

Duct Sealing with Mastic Sealant
Mount Prospect’s original 1955-1972 sheet-metal duct systems were assembled with snap-lock seams and tape that has dried, cracked, or fallen away over 50-70 years. We seal accessible joints with mastic sealant, a brush-applied compound that remains flexible and creates a permanent airtight bond at temperatures from -20°F to 350°F. On a typical Mount Prospect ranch, we’ll find 15-30 linear feet of accessible trunk line in the basement where mastic sealing restores designed static pressure and stops conditioned air from bleeding into wall cavities. A standard mastic sealing job on accessible basement trunk runs in Mount Prospect runs $280-$450.

Metal Duct Repair
Original octopus plenum systems in Mount Prospect homes were built from 26- or 28-gauge galvanized steel that corrodes at the bottom where condensate collects, or dents where subsequent HVAC contractors stepped on the trunk during furnace replacements. We cut out damaged sections, fabricate replacement pieces on-site, and seal with mastic and mechanical fasteners. Metal duct repair in Mount Prospect typically runs $340-$620 depending on access and the extent of corrosion. Every cut is photographed before and after, and the photo record is delivered as part of your standard job documentation.

Flex Duct Repair
Many Mount Prospect ranches and split-levels received flex-duct additions during 1990s-2000s HVAC upgrades - new basement-to-register runs or crawl-space trunk lines that sag, crush, or separate at collar connections over time. Flex duct is particularly vulnerable in Mount Prospect’s low-clearance crawl spaces, where summer humidity promotes mold growth on the outer vapor barrier and the inner liner deteriorates. We replace collapsed or mold-compromised flex runs with properly supported new material, sized to match the original CFM design. Flex duct repair or replacement in Mount Prospect typically costs $180-$340 per run.

Air Leak Repair
Disconnected legacy branches are a specific failure mode we encounter repeatedly in Mount Prospect. When high-efficiency furnaces were retrofitted in the 1990s-2000s, contractors often routed new venting through existing duct chases and left original supply branches sealed behind drywall. These dead ends load the plenum with stagnant debris and create pressure imbalances that make some registers weak and others noisy. We locate the disconnect with camera inspection, cut minimal access, reconnect the branch with a mastic-sealed transition, and post-test static pressure to confirm the repair. Air leak repair involving hidden disconnects in Mount Prospect typically runs $450-$890 depending on drywall access and the complexity of the reconnection.

Duct Insulation
Original duct liner in Mount Prospect’s 1955-1972 systems was fiberglass bonded to the interior metal surface. After 50-70 years, this liner degradates and sheds particles into the airstream. Where the liner is compromised but the metal shell is sound, we can apply new external insulation or, in select cases, line the duct with approved replacement material. Duct insulation work in Mount Prospect ranges from $380-$720 for accessible basement trunk lines.

What happens when you call
- 1
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 Mount Prospect
Our crews carry professional-grade equipment from Rotobrush, Abatement Technologies, and Guardsman - trade-recognized brands that we name specifically so Mount Prospect homeowners can verify specifications before any work begins. We stock common collar sizes, mastic compounds, and flex-duct diameters on every truck serving the Mount Prospect area, which means most repairs don’t require a return visit for parts. If your system includes Aprilaire or Honeywell air-cleaning components integrated with the ductwork, we document their condition during inspection and note any recommended coordination with your HVAC service provider.
Common Duct Repair & Sealing Problems We See in Mount Prospect Homes

- Deteriorated original fiberglass duct liner. The 1955-1972 buildout in Mount Prospect used fiberglass-lined sheet metal that is now shedding particles after 50-70 years. Replacement furnaces were installed, but the liner was never addressed. We find this in nearly every original plenum we open.
- Disconnected legacy branches from 1990s-2000s furnace retrofits. High-efficiency furnace installations routed new venting through old duct chases and left original supply runs sealed behind drywall. These dead ends trap debris and mold, and they’re invisible without camera inspection of the main plenum.
- Failed flex-duct transitions from HVAC upgrades. Flex-duct additions joined to original metal runs at hard-to-reach points - especially in Mount Prospect’s low crawl spaces - where sagging, crushed sections, or failed collar tape create debris traps and airflow restrictions.
- Summer mold colonization in crawl-space trunk lines. Mount Prospect’s humid July and August conditions, combined with cool conditioned air in unconditioned crawl spaces, produce condensation that supports mold growth on duct exteriors and interiors. This is particularly common in ranches along Algonquin Road and Busse Road corridors where crawl-space ventilation was minimal in original construction.
Pricing for Duct Repair & Sealing in Mount Prospect, IL
We publish actual ranges because Haven Standard Clause 1 requires a written price before any work starts. Here is what duct repair and sealing costs in Mount Prospect’s market:
| Service | Typical Range in Mount Prospect |
|---|---|
| Mastic sealing, accessible basement trunk (up to 30 linear ft) | $280-$450 |
| Metal duct repair / section replacement | $340-$620 |
| Flex duct repair / replacement per run | $180-$340 |
| Air leak repair with hidden disconnect (drywall access required) | $450-$890 |
| Duct insulation / re-lining, accessible trunk | $380-$720 |
These are whole-system prices, not per-vent teaser rates. What moves a job toward the higher end: crawl-space access requiring additional safety setup, multiple disconnected branches, or plaster-and-lath construction that demands specialized cutting and repair. What keeps it lower: open basement access, single-point repairs, and metal trunk lines in good structural condition. Every estimate is free, written, and delivered before any panel comes off. Bring a competitor’s written quote; under Haven Standard Clause 5, we provide a Free Second Opinion at no cost.
We Also Serve Cities Near Mount Prospect

Our crews run daily routes through Des Plaines, Arlington Heights, Palatine, and Elk Grove Village. If you’re near the Mount Prospect border in one of these communities, the same written-price protocol and documented photo record apply. Duct Repair & Sealing in Mount Prospect remains our core service area for this specialized work, but we coordinate scheduling across the full northwest corridor from our Chicago office.
Serving Mount Prospect, IL - Our Local Coverage Area
We’re based in the Mount Prospect 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 Mount Prospect

The musty smell is usually mold colonizing a disconnected legacy branch or a crushed flex run in a humid crawl space. Standard duct cleaning doesn’t reach dead-end branches sealed behind drywall, or flex sections that have separated from the trunk and are loading stagnant air into the plenum. Camera inspection locates the source, and mastic-sealed repair or replacement eliminates the mold reservoir. Call (224) 344-8881 for an exact quote - estimates are free.
The weak register is likely fed by a branch that was disconnected or partially blocked during the high-efficiency furnace retrofit. In Mount Prospect’s 1960s split-levels, we regularly find that new venting was routed through existing duct chases and original supply runs were sealed behind finished basement walls. The register still “works” because it pulls slight induction air, but designed CFM is gone. Camera inspection of the main plenum confirms the disconnect, and minimal-access repair restores flow. Call (224) 344-8881 for an exact quote - estimates are free.
Most 60-year-old systems in Mount Prospect need both. The original fiberglass duct liner is typically deteriorating and shedding particles; cleaning alone doesn’t restore a compromised liner. Metal seams have dried tape or failed snap-locks that leak conditioned air. And many have hidden disconnects from prior furnace retrofits. We inspect with a camera, show you what we find, and quote repair separately from cleaning so you can decide based on documented evidence. Call (224) 344-8881 for an exact quote - estimates are free.
Flex duct is common as an add-on but was not original to 1955-1972 construction. Mount Prospect ranches typically have sheet-metal basement trunks with flex-duct additions from 1990s-2000s HVAC upgrades. These flex runs fail at collar connections, sag in low crawl spaces, and crush where they pass through tight framing. The failure is usually at the transition to original metal, not in the flex material itself. We replace failed sections with properly supported new runs and mastic-sealed collars. Call (224) 344-8881 for an exact quote - estimates are free.
We feed a camera into the main plenum and trace each branch listed on the panel. In Mount Prospect’s older homes, we regularly find that a branch runs 8-12 feet and dead-ends behind drywall where a 1990s furnace retrofit abandoned the original route. The camera shows the termination point, and we correlate that with the register map to identify which room is affected. Repair requires cutting a minimal access panel, reconnecting the branch, and sealing with mastic. Every step is photographed. Call (224) 344-8881 for an exact quote - estimates are free.
What to Expect When You Call CleanRun
Every call is answered by a live person, 24/7. We’ll schedule a technician visit to your Mount Prospect home, and you’ll receive the technician’s name and background verification before arrival. The technician will inspect your duct system with a camera, show you what we find on a tablet, and deliver a written price before any work begins - Haven Standard Clause 1, no exceptions.
If you proceed, the work is performed with equipment from Rotobrush, Abatement Technologies, and Guardsman. Every duct run is photographed before and after. The photo record, written scope, and 365-Day Done Right Promise are delivered as standard documentation before the crew leaves. If the work is not right, we make it right - backed in writing, not subject to manager approval.
Call (224) 344-8881 for a free estimate on duct repair and sealing in Mount Prospect. Or bring any competitor’s written estimate; under Haven Standard Clause 5, we’ll provide a Free Second Opinion at no cost.
Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Mount Prospect since 2013.




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