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 Castle Rock
Duct repair and sealing in Castle Rock typically runs $280-$780 for most residential jobs, with full-system sealing on larger homes reaching $1,200-$1,800. We dispatch crews from our Denver office and serve Castle Rock daily, including Castle Rock neighborhoods from The Meadows to Crystal Valley Ranch. Call (720) 315-7291 for a written estimate before any work starts.
Castle Rock’s housing stock tells a specific story. The production-built subdivisions that define this market - Terrain, The Meadows, Crystal Valley Ranch - were built fast, with ductwork installed before drywall finishing and often never blown out before the homeowner moved in. What we find inside isn’t years of household accumulation. It’s construction debris that was sealed into the system from day one, now masking disconnected runs, crushed flex, and joints that were never properly sealed with mastic. Our Duct Repair & Sealing team treats this as the starting point, not the exception.
Why CleanRun Air Duct Cleaning Littleton Is Castle Rock’s Preferred Duct Repair & Sealing Company
We’ve served Castle Rock since adding the market to our route schedule in 2015, and the pattern in local homes is consistent enough that our technicians now carry extra flex duct and mastic specifically for the post-construction debris scenarios common here. Our Castle Rock Dryer Vent Cleaning services address similar construction-related buildup issues. The photo records from Castle Rock jobs - included on every visit - show the same findings repeatedly: supply boots packed with drywall joint compound dust, flex runs crushed behind chases, and plenum joints that were taped but never sealed.
Our Castle Rock customers receive the same documented deliverables as every other market: a written price before work begins (Haven Standard Clause 1), a 365-Day Done Right Promise backed in writing, and a complete photo record of every duct run before and after service. Technicians are background-checked and uniformed under Haven Standard Clause 3: Verified Crews, and identified by name before arrival. Tomas Reyes, who leads CleanRun, established the documented photo record practice in 2013 and maintains it as a non-negotiable standard on every job.
We do not offer “call for a quote” pricing. We offer written estimates, delivered before any panel comes off, with a Free Second Opinion available on any competitor’s written estimate.
Our Duct Repair & Sealing Services in Castle Rock

Duct Sealing
Castle Rock’s multi-zone systems in 2,500-5,000+ square foot homes run long duct runs to second and third stories. Joints that were taped but not mastic-sealed during construction leak conditioned air into attics and wall cavities, driving up utility bills and creating pressure imbalances. We seal with mastic compound at every joint, register boot, and plenum connection, then verify with static pressure measurement. A typical duct sealing job in Castle Rock runs $450-$920 depending on system size and accessibility.

Flex Duct Repair
Flex duct gets crushed during construction, chewed by rodents in crawl spaces, or simply pulls loose at collars over time. In Castle Rock’s newer subdivisions, we regularly find flex runs that were never fully connected at the supply boot - hidden behind drywall and pumping conditioned air into the chase instead of the room. We replace damaged sections with new insulated flex, secure with mechanical fasteners and mastic, and photograph every connection. Flex duct repair in Castle Rock typically costs $180-$340 per run, with multi-run jobs bundled at $480-$780.

Metal Duct Repair
Older metal ductwork in Castle Rock’s late-1990s builds develops corrosion at seams, separated sections at hangers, and holes from contact with roofing nails or framing fasteners. We patch with galvanized sheet metal, seal with mastic, and reinforce with mesh where structural integrity is compromised. Metal duct repair runs $220-$560 in Castle Rock, with full section replacement reaching $680-$1,100 for large galvanized trunk lines.

Mastic Sealant Application
Tape fails. Mastic doesn’t. We apply fire-rated mastic compound (Abatement Technologies and Honeywell-specified products) with a brush or spray applicator at every joint, seam, and penetration. This is standard on every sealing job we perform in Castle Rock, not an upsell. The material remains flexible through Colorado’s temperature swings and seals against the fine particulate dust that Castle Rock’s northeast winds push through the system.

Duct Insulation
Uninsulated or degraded duct insulation in attics and crawl spaces loses thermal efficiency and creates condensation points. We install foil-faced fiberglass insulation at R-6 or R-8 values, sealed with matching tape and mastic at all seams. Duct insulation in Castle Rock runs $2.80-$4.20 per linear foot, with typical whole-system jobs at $680-$1,400.

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 Castle Rock
CleanRun technicians carry professional-grade equipment from Nikro, Honeywell, Aprilaire, and Abatement Technologies - brands customers can look up independently before agreeing to any price. We stock common flex duct diameters, mastic compounds, and register boots in our Denver warehouse, which means most Castle Rock repairs don’t wait on parts. For specialized components in larger production homes, we source from regional distributors with next-day availability to the Castle Rock area.
Common Duct Repair & Sealing Problems We See in Castle Rock Homes

- Drywall joint compound dust packed around supply boots. In newer subdivisions like Terrain at Castlerock, this construction debris masks disconnected or crushed flex runs until airflow drops noticeably on the second floor. The dust hardens over time and restricts register output even when the duct is structurally intact.
- Leaks at poorly sealed joints in long multi-zone runs. Castle Rock’s larger homes have duct runs stretching 40-60 feet to distant zones. Joints that were taped but never mastic-sealed after construction separate slowly under thermal expansion, leaking conditioned air into attics and creating pressure imbalances between floors.
- Wildfire smoke residue in unsealed return ducts. Castle Rock’s position in the foothills transition zone puts it directly in the path of Front Range wildfire smoke events. Fine ash and combustion particles enter through unsealed return duct seams, deposit on duct walls, and create odors that standard 1-inch pleated filters cannot fully address.
- Crushed flex runs behind drywall chases. Production builders in Crystal Valley Ranch and The Meadows often route flex through tight framing cavities where it gets compressed during insulation or drywall installation. The restriction reduces airflow by 30-50% before the homeowner ever notices a temperature difference.
Pricing for Duct Repair & Sealing in Castle Rock, CO
We publish ranges because Haven Standard Clause 1 requires a written price before any work starts. Here’s what duct repair and sealing costs in Castle Rock’s market:
| Service | Typical Range |
|---|---|
| Single flex duct repair/replacement | $180 - $340 |
| Multi-run flex repair (2-4 runs) | $480 - $780 |
| Metal duct patch or section repair | $220 - $560 |
| Full metal section replacement | $680 - $1,100 |
| Duct sealing (mastic, typical home) | $450 - $920 |
| Whole-system sealing (large home, 4,000+ sq ft) | $1,200 - $1,800 |
| Duct insulation (per linear foot) | $2.80 - $4.20 |
| Post-construction debris removal + sealing package | $680 - $1,400 |
Factors that move the price: system size, attic/crawl accessibility, number of zones, and whether we’re repairing damage found during a cleaning or performing standalone sealing. Every estimate is free, written, and delivered before any work begins. Call (720) 315-7291 to schedule.
We Also Serve Cities Near Castle Rock

CleanRun crews serve Parker, Littleton, Englewood, and Evergreen from our Denver office, with the same documented photo record and written pricing standard applied to every job. If you’re in a Castle Rock-adjacent community and found this page searching for Duct Repair & Sealing in Castle Rock, we likely cover your area as well - call to confirm routing.
Serving Castle Rock, CO - Our Local Coverage Area
We’re based in the Castle Rock 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 Castle Rock

Because the ductwork was installed before drywall finishing and never properly cleaned before you moved in. In Castle Rock’s production-built subdivisions, supply boots are routinely packed with drywall joint compound dust, flex runs get crushed behind chases during construction, and joints are taped but not mastic-sealed. The home is new. The duct system inside it has been dirty since closing. We regularly perform repair and sealing on homes where the buyer has lived there less than a year. Call (720) 315-7291 for a written estimate - we’ll show you what the camera finds.
The persistent northeast winds across the Palmer Divide force fine particulate dust into homes at rates higher than Denver or Colorado Springs. Unsealed return ducts pull this dust directly into the system, accelerating fouling and bypassing standard filtration. Proper mastic sealing at all return duct joints and plenum connections is the primary defense, and it’s why we emphasize sealing over cleaning alone in Castle Rock’s wind-exposed locations. A sealed system stays cleaner longer and protects HVAC components from abrasive dust accumulation.
Yes, when the odor source is residual ash and combustion particles deposited in ductwork. Castle Rock’s foothills position makes it vulnerable to Front Range wildfire smoke events, and fine particles enter through unsealed return seams where standard filters cannot reach them. We seal the leaks to prevent future infiltration, then remove deposited residue with negative-pressure extraction and agitation. If the odor has penetrated porous building materials beyond the ducts, we identify that during inspection and note it in the written scope. Call (720) 315-7291 to discuss what our cameras have found in similar Castle Rock homes.
In Terrain at Castlerock, our tech pulled registers in a 3,400-square-foot two-story and found supply boots clogged with joint compound dust and two flex runs crushed behind the drywall chase. We ran agitation tools under negative pressure, then reconnected and sealed the runs with mastic and new flex, restoring balanced airflow to the second floor. This pattern - construction debris plus mechanical damage hidden behind finished surfaces - is typical in Castle Rock’s 2,500-5,000+ square foot production homes, where the scale of ductwork multiplies the number of potential failure points.
NADCA (National Air Duct Cleaners Association) provides voluntary guidelines for duct cleaning and restoration; Castle Rock does not have a local mandate requiring NADCA certification for sealing work. CleanRun follows NADCA-recommended practices for access, mechanical agitation, and containment as part of our H.A.V.E.N. Standard, and we document our methods in the photo record delivered with every job. If a Castle Rock homeowner specifically requests NADCA-compliant documentation for warranty or real estate purposes, we provide it in writing. The 365-Day Done Right Promise applies regardless of which standard framework is referenced.
Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Castle Rock since 2013 with written prices before every job and documented photo records on every visit.




Before
After
Before
After