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 Littleton
Duct repair and sealing in Littleton typically runs $280-$680 for most residential systems, with full encapsulation of degraded duct board reaching $890-$1,400 in older Ken Caryl Ranch and Columbine homes. Most jobs are scheduled within 3-5 business days, and every visit starts with a written price before any panel comes off. Our crews are dispatched from our Denver office and serve Littleton neighborhoods daily, from the foothill-adjacent streets of Ken Caryl to the split-level corridors near Bow Mar and the Leawood area.
We know these homes. The 1979-1990 builds with original fiberglass duct board. The flex duct connections that have cycled through forty Colorado winters. The Chinook winds that drive fine dust through return-air pathways faster than standard filters can catch. That local knowledge changes what we find, how we fix it, and what we document before we leave. Call (720) 799-2292 for a free written estimate.
Why CleanRun Air Duct Cleaning Denver Is Littleton’s Preferred Duct Repair & Sealing Company
CleanRun has served Littleton since our first jobs in 2013, and we’ve built our reputation here on one practice that sounds simple until you realize how rare it is: we photograph the inside of every duct run before we touch it, and we photograph it again when we’re done. Littleton homeowners see the difference between vacuum noise and actual source removal. That documented photo record is included on every visit, not sold as an upgrade.
Our technicians are background-checked, uniformed, and identified by name before arrival - Haven Standard Clause 3: Verified Crews. Tomas Reyes, who leads CleanRun, established the H.A.V.E.N. Standard in 2013 to eliminate the industry’s bait-and-switch pattern. Every Littleton job gets a written price before work starts, every time, under Haven Standard Clause 1. No exceptions. No “call for pricing.” Bring a competitor’s written estimate and we’ll put our number next to it for free.
The 365-Day Done Right Promise backs every job in writing. If the work isn’t right, we make it right. Not a policy subject to manager approval. A written guarantee.
Our Duct Repair & Sealing Services in Littleton

Duct Sealing
Most Littleton homes we inspect leak 20-30% of conditioned air before it reaches the registers. In the Columbine corridor and Ken Caryl Ranch, where original duct board has spent four decades expanding and contracting through Chinook temperature swings, those leaks often sit at delaminated seams invisible from the outside. Our duct sealing process starts with a pressure-pan test or duct-blaster measurement to quantify leakage, then targets each failure point with mastic sealant or foil-backed tape rated for the temperature cycling these systems endure. A typical duct sealing job in Littleton runs $340-$620 for a single-system home. We seal first, then verify with post-repair testing.

Flex Duct Repair
Flex duct - the insulated flexible tubing connecting trunk lines to room registers - fails predictably in Littleton’s dry climate and wind-exposed locations. The plastic inner liner becomes brittle after 20+ years, and the fiberglass insulation compresses where ducts sag or get stepped on in attics. We replace collapsed or torn flex duct with new R-6 or R-8 insulated runs, support them properly to prevent future sagging, and seal each collar connection with mastic. Flex duct repair in Littleton typically costs $180-$340 per run, depending on attic access and length. Homes near the foothills, where Chinook gusts pressurize attic spaces, see accelerated flex duct degradation at connection points.

Metal Duct Repair
Galvanized steel trunk lines in Littleton’s older split-levels and ranches develop seam separation and rust-through where condensation collects in unconditioned crawl spaces. We cut out damaged sections, fabricate replacement fittings, and seal with high-temperature mastic. Metal duct repair runs $260-$520 per section in most Littleton homes. Where the original system includes a plenum - the distribution box attached to your furnace - we inspect for cracks at the flue collar and filter rack, common failure points in systems that have cycled through thousands of Colorado heating seasons.

Duct Insulation
Uninsulated or degraded duct insulation in Littleton attics and crawl spaces wastes energy and creates condensation issues during shoulder seasons. We install foil-faced fiberglass insulation or closed-cell wrap on supply trunks, with particular attention to the temperature differentials these systems see at 5,350 feet elevation. Duct insulation work in Littleton ranges from $420-$780 for partial-system jobs to $1,100-$1,600 for full trunk-line wrapping. In Ken Caryl Ranch homes with original duct board, insulation replacement often pairs with encapsulation to contain shedding liner - a combination repair that generic duct cleaners frequently miss.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Before
AfterTrusted Brands We Service in Littleton
Our equipment roster includes Rotobrush mechanical agitation systems, Nikro negative-pressure extractors, Honeywell media air cleaners, and Aprilaire whole-home humidifiers and filtration - brands customers can look up independently before agreeing to any price. We stock common repair components for Littleton’s dominant HVAC brands locally, so most flex duct repairs and sealing jobs complete in a single visit without waiting on parts. For duct board encapsulation, we use Abatement Technologies coating systems and Guardsman-recommended application protocols. Every product and piece of equipment is named on your written scope before work begins.
Common Duct Repair & Sealing Problems We See in Littleton Homes

- Delaminated fiberglass duct board in Ken Caryl Ranch and Columbine homes. The original 1980s duct board used in these planned communities has separated along interior seams, shedding fiberglass fibers into the airstream. Standard cleaning without sealing makes the problem worse by disturbing loose material. We encapsulate the liner with a rated coating, then seal the seams.
- Chinook-driven dust infiltration through degraded return-air pathways. Littleton’s position at the Front Range foothills exposes homes to periodic wind events that pressurize attics and crawl spaces, forcing fine particulates through gaps in return ductwork. Flex duct connections at collars and boots are common failure points.
- Low winter humidity driving dust deep into duct runs. At humidity levels often below 20%, fine dust remains suspended longer and penetrates deeper into the system. “Clean” ducts still test high for particulates unless source removal is paired with sealing that prevents re-infiltration.
- Wildfire smoke residue in duct systems after active fire seasons. Littleton’s foothill proximity means recurring exposure to Front Range wildfire smoke. Combustion particulates adhere to duct interiors and standard filter changes do not remove them. Source removal with HEPA filtration, followed by sealing, is required.
Pricing for Duct Repair & Sealing in Littleton, CO
Here’s what duct repair and sealing actually costs in Littleton’s market:
| Service | Typical Range |
|---|---|
| Duct sealing (single system, mastic + tape) | $340-$620 |
| Flex duct repair / replacement (per run) | $180-$340 |
| Metal duct repair (per section) | $260-$520 |
| Duct insulation (partial system) | $420-$780 |
| Duct board encapsulation + sealing | $890-$1,400 |
| Full duct insulation (trunk-line wrapping) | $1,100-$1,600 |
These are whole-system prices, not per-vent teaser rates. What moves a job toward the higher end: multiple attic access points, extensive encapsulation work, or systems with significant contamination requiring source removal before sealing can begin. Every price is delivered in writing before work starts - Haven Standard Clause 1. No exceptions. Call (720) 799-2292 for your exact estimate; estimates are free.
We Also Serve Cities Near Littleton

Our Duct Repair & Sealing crews work throughout the metro area, including Littleton and surrounding communities: Englewood to the north, Parker to the southeast, Denver proper, and Aurora to the east. Scheduling and dispatch are coordinated from our Denver office, with crews serving each area locally.
Serving Littleton, CO - Our Local Coverage Area
We’re based in the Littleton 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 Littleton

Every 2-3 years for homes on unpaved roads or with active wood heat, compared to the 3-5 year interval typical for filtered natural-gas systems in developed neighborhoods. Wood heat produces combustion particulates that adhere to duct interiors, and unpaved road dust loads filters faster than urban environments. We recommend annual filter changes with MERV 11 or higher, and a camera inspection every other heating season to catch flex duct degradation before it becomes a leakage problem. Call (720) 799-2292 to schedule an inspection.
The original 1980s fiberglass duct board in Ken Caryl Ranch has frequently delaminated along interior seams, creating a hidden air-quality hazard that standard cleaning alone worsens by disturbing loose fibers. Sealing - specifically encapsulation with a rated coating - is required to contain the shedding liner before it migrates into living spaces. This failure mode is rare in newer Highlands Ranch or Centennial builds with metal or modern flex duct systems. We document the condition with pre-repair photography and include the encapsulation scope in your written price.
Outbuilding ductwork - shops, guest houses, converted barns - typically uses exposed flex duct or uninsulated metal that sees wider temperature swings and more physical damage than main-house systems. Our process includes camera inspection of each run, replacement of damaged flex or fabricated metal sections, mastic sealing of all joints, and insulation wrap where the duct passes through unconditioned space. We price outbuilding systems as a separate scope from the main house, with written costs for each. Most outbuilding repairs in the Littleton area run $420-$890 depending on system size and access.
Yes, but only when paired with source removal of existing particulates. Sealing alone traps smoke residue and dust inside the system; source removal alone leaves pathways open for re-infiltration. Our approach for Littleton homes: negative-pressure extraction with HEPA filtration to remove accumulated combustion particulates and windborne dust, then duct-blaster-verified sealing of return-air pathways and trunk seams to prevent re-entry. The documented photo record shows the before condition and the post-sealing verification data.
MERV 11 minimum, MERV 13 if your system can handle the static pressure drop. Littleton’s combination of Chinook dust, wildfire smoke exposure, and low winter humidity that keeps particulates suspended demands tighter filtration than coastal or more humid climates. After sealing reduces system leakage, the filter actually does its job instead of bypassing air around it. We check static pressure during our repair visit and recommend the highest MERV rating your blower can support without overworking the motor. Call (720) 799-2292 and we’ll test it.
Written by Tomas Reyes, Owner at CleanRun Air Duct Cleaning Denver, serving Littleton since 2013.




Before
After
Before
After