Air Duct Cleaning & Dryer Vent Cleaning in San Anselmo, CA

San Anselmo sits at the bottom of the Ross Valley, and the creek is why this town needs a different conversation than most. Water has been into these crawl spaces repeatedly. On New Year's Eve in 2005 it put more than four feet through downtown, and there have been smaller winters since that nobody outside the neighborhood remembers.

Ducts run through those crawl spaces. When the insulation wrapped around soft ducting takes on water it does not dry out down there, and the EPA is clear that insulation which has gotten wet or moldy cannot be effectively cleaned and should be removed and replaced. That is a real distinction. It is the difference between a service that solves the smell and one that moves it around for a season.

So the first thing we do here is look, in the crawl space, with a light, before quoting anything. Sometimes the answer is a straightforward cleaning. Sometimes it is a section of duct that should have been replaced years ago, in a house where somebody has been sold three cleanings instead. Call today for a free quote on HVAC system cleaning or dryer vent cleaning in San Anselmo.

Replacing a Section of Duct Instead of Cleaning It

When flood water has soaked the insulation on a run of flex duct, that section is done, and no amount of cleaning changes it. Replacing it is a smaller job than people assume. We cut out the affected run, fit new duct, seal the connections properly with mastic rather than tape, and support it so it does not sag back into the same low spot. On a typical San Anselmo crawl space that is a section or two, not the whole system, because water reaches what it reaches and leaves the rest alone. The reason to do it rather than clean around it is straightforward: wet insulation inside a duct is a place for mold to grow that you cannot see, cannot reach, and cannot dry out down there. Cleaning it moves the surface material and leaves the actual problem in the wall of the duct. Upstream in Fairfax the same call comes up after the same storms.

Mold in a Duct System, and What the Standard Actually Says

Mold is one of the three conditions that genuinely warrants cleaning a system, and it is also the one most often used to sell work that is not needed. So here is the honest version. What matters is substantial visible mold growth on hard surfaces inside the ducts or on other components. Not a musty smell on its own, which can come from a dozen places. Not a sample sent to a lab you have never heard of. If we find it, we will show it to you before we quote anything. If the growth is on insulation rather than on sheet metal, that material comes out and gets replaced rather than cleaned, which is the same rule as the flood damage above. And if what is actually going on is a wet crawl space feeding moisture into the system continuously, cleaning the ducts without fixing that is a service you will be buying again next year.