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 Air Duct Cleaning Across Belmont
Air duct cleaning in Belmont typically costs $430-$690 for a single-system home and $890-$1,400 for a three-system hillside property. Most Belmont jobs take four to seven hours depending on the number of duct runs, system count, and what our camera inspection finds once we open the plenum. We serve every neighborhood in Belmont, from the Ralston Avenue corridor up into the Belmont Hills. Call (806) 606-6902 for a written price before any work starts.
Belmont’s fog-trapping geography creates a set of duct problems you won’t find in San Mateo or Redwood City. Our crews who work Belmont know what to look for before they even pull the first register. That local knowledge matters, because the cost of missing a fog-driven mold pattern in a split-level crawl space is a cleaning that fails within one season.
Why CleanRun Air Duct Cleaning Is Belmont’s Preferred Air Duct Cleaning Company
Belmont homeowners tend to ask for documentation before they agree to anything, and that’s exactly how we’ve operated since 2013. Every job starts with a written price under Haven Standard Clause 1. Every job ends with a documented photo record of every duct run, inside, before and after. That standard applies to every one of the 52,000+ homes we’ve served.
Tomas Reyes, who leads CleanRun, built the company around a simple premise: a homeowner should be able to see exactly what they paid for, even when the work is inside a wall or a crawl space. That’s why our techs photograph the inside of every supply and return run, deliver the images as part of the standard job record, and back the work with the 365-Day Done Right Promise in writing.
Callers reach a live person who can schedule a Belmont visit directly, and every technician is background-checked, uniformed, and identified by name before arrival. We publish our license number on the page, not in a footer. If you have a written estimate from another company, bring it. We’ll put our number next to it in writing, free.
Our Air Duct Cleaning Services in Belmont

Residential Duct Cleaning
A typical single-system ranch along the Ralston corridor in Belmont runs $430-$690. We clean the full supply and return network, not just the registers. In 1950s and 1960s homes with original sheet-metal ducting, that means addressing mastic failures and condensation points, not just vacuuming dust. Every run is photographed before and after so you can see the difference between debris removal and actual clean metal.

Commercial Duct Cleaning
Belmont’s commercial spaces along El Camino Real and the light-industrial pockets near Harbor Boulevard need a documented scope of work, especially when a lease or health inspection requires it. We provide the same written price, photo record, and warranty on commercial systems as we do on homes. Scheduling is coordinated so a Belmont business isn’t closed longer than necessary.

Supply Duct Cleaning
Supply ducts carry conditioned air from your furnace or air handler to every room, and in Belmont’s hillside homes, the downhill supply runs are the first to grow mold. Why? The fog-exposed crawl space on the downhill side of a split-level stays near 100% relative humidity for months. Warm interior air meets that cold, damp duct exterior, condensation forms inside, and mold follows. Our negative-pressure extraction pulls that contamination out, and our camera verifies the full supply run. Supply duct cleaning in Belmont for a single system runs $290-$460.

Return Duct Cleaning
Return ducts are what draw air back to the system, and in a 1968 tract ranch they’re often the dirtiest part of the house because they pull from every room and concentrate everything in one low, humid corridor. Return duct cleaning in Belmont runs $220-$380 for a single-system home. We include it in every full-system job, and the before-and-after photo record shows exactly what came out of the return side, run by run.

Full System Cleaning
A full system cleaning covers the supply side, the return side, the plenum, and the accessible duct runs in between. For most Belmont homes, that’s $430-$690 per system. The important qualification: a three-system hillside house with two furnaces and a separate air handler is not one system. We price per system, in writing, before work begins, so there’s no ambiguity about what “full” means.

Video Inspection
Video inspection is the most important service we offer in Belmont, and we say that specifically because of what this city’s fog does to hidden duct runs. A camera pushed through a supply run shows condensation damage, failed mastic, delaminated flex liner, and the downhill-side mold pattern that generic cleaning misses. In Belmont hillside homes, we recommend video inspection on every job, and we include it as a standard part of our documentation record. A standalone video inspection of a single system runs $180-$250, and it’s credited back if you proceed with cleaning.

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.
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AfterTrusted Brands We Service in Belmont
Our techs run professional-grade equipment from Rotobrush, Abatement Technologies, and Guardsman, because homeowner-grade shop vacuums can’t produce the negative pressure needed to pull debris from a 30-foot duct run. Rotobrush agitation loosens what’s stuck to the duct walls; Abatement Technologies HEPA filtration captures it; Guardsman sanitizing and deodorizing agents treat what remains. When a Belmont homeowner asks what equipment is being used on their system, the answer is the same brands we’d list on the written scope. You can look them up before we arrive.
Common Air Duct Cleaning Problems We See in Belmont Homes

- Downhill-side mold in split-level crawl spaces. On the fog-exposed downhill side of a Belmont hillside split-level, the crawl space stays saturated for months at a time. Duct runs crossing that space sweat on the inside, and mold colonizes the downhill supply run while the uphill side of the same system stays clean. This is a condensation gradient we almost never see in flat San Carlos.
- Original 1960s flex duct with failed mastic. Ralston corridor ranches built between 1955 and 1975 often retain their original flex duct. The mastic at every joint has dried and cracked, the insulation is damp, and the liner is delaminating. Cleaning that duct without re-sealing and re-insulating just re-seeds the mold next fog season.
- Non-standard multi-level routing above Belmont Avenue. Hillside custom builds and semi-customs above Belmont Avenue have duct routing that doesn’t follow any standard pattern. Long runs through unventilated crawl spaces hide disconnected branches and blocked return paths that only a video inspection will reveal.
- Condensation inside unconditioned attics. The Belmont Hills concentrate the marine layer, and attics that never fully dry out produce condensation inside duct runs, not just on the exterior. We’ve pulled apart supply runs where the inside of the metal was sweating. That moisture feeds mold and degrades insulation from the inside out.
Pricing for Air Duct Cleaning in Belmont, CA
A single-system home in the Belmont flatlands typically runs $430-$690 for a full supply and return cleaning with video inspection included. A three-system hillside property, which is common above Belmont Avenue, runs $890-$1,400 because each furnace or air handler serves its own duct network and each gets cleaned, documented, and priced separately. The factors that move the price inside that range are the number of duct runs, the length of those runs, the amount of debris contamination we find, and whether the system has been cleaned in the last decade. We don’t price per vent and we don’t use a low coupon price to get a van in the driveway. You receive one flat price per system, in writing, before any panel comes off. Call (806) 606-6902 for an exact quote: the estimate is free, and it’s delivered as a written scope, not a verbal range.
We Also Serve Cities Near Belmont

Our crews serve the full Peninsula corridor. If you’re across the border in San Carlos, San Mateo, Redwood City, or Burlingame, you can reach us at the same number and expect the same written-price standard. But this page is specifically about Air Duct Cleaning in Belmont, because Belmont’s fog-driven duct failures deserve their own conversation. You can also learn more about our full Air Duct Cleaning process, which applies to every home we serve.
Serving Belmont, CA - Our Local Coverage Area
We’re based in the Belmont 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 - Air Duct Cleaning in Belmont

Because the work is inside a duct run you cannot see, and in Belmont’s fog-exposed hillside crawl spaces, the most likely failure point is the downhill run that never dries out. A video inspection confirms that the full supply and return path is clean, not just the first few feet from the register. We include the camera record as a standard deliverable, not an add-on. Call (806) 606-6902 to ask about inspection-first pricing for your specific system.
The fog layer means we look for condensation damage first, before we even look at debris load. In a 1960s Ralston corridor ranch, the original sheet-metal and early flex duct crosses between heated rooms and a crawl space that stays moist for months. Our techs check for sweating duct walls, failed mastic at joints, and liner delamination in flex duct, because those are the conditions that turn a routine cleaning into a recurring mold problem if they’re not documented and addressed. Call (806) 606-6902 for a written scope that includes a fog-specific inspection.
Because a hillside house with two furnaces and a separate air handler has three independent duct networks, and each one takes real time to clean, inspect, and document. A single flat price for “the house” hides whether the second furnace’s ductwork was actually touched. We write a separate price per system, per Haven Standard Clause 1, so you know exactly which parts of the house were cleaned and what each one cost. Call (806) 606-6902 for a per-system quote in writing.
You should expect a written scope of work before the job, a written price per system before any panel comes off, and a photo record of every duct run before and after cleaning. That photo record is a standard deliverable on every CleanRun job, not an upsell. It shows the inside of the supply and return runs, the condition before we started, and the condition when we finished. If a company won’t put that in writing, ask why. Then call (806) 606-6902.
Cleaning removes the mold that’s present, but it cannot stop the condensation gradient that caused it. In a Belmont split-level where the downhill crawl space stays saturated through the fog season, the duct runs will sweat again unless the underlying moisture and insulation failures are addressed. We document that in our photo record and written scope, and we’ll tell you plainly what the camera shows: cleaning fixes the current contamination, but re-insulating and sealing the downhill runs is what stops it from returning. Call (806) 606-6902 and we’ll walk you through what a full fog-specific scope looks like.
Get a Written Price for Air Duct Cleaning in Belmont
Belmont homes hide duct problems that flat neighborhoods don’t, and we’d rather show you than tell you. Call (806) 606-6902 and we’ll schedule a Belmont visit, inspect your systems, and give you a written price per system before any work starts. Every job includes the documented photo record, the 365-Day Done Right Promise, and the full H.A.V.E.N. Standard. Bring a competitor’s written estimate and we’ll put our number next to it, free. That’s the standard we’ve held since 2013, on every one of our 52,000+ homes served.
Written by Tomas Reyes, Owner at CleanRun Air Duct Cleaning, serving Belmont since 2013.




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