Air Duct Cleaning in Mill Valley, CA

Frequently Asked Questions

My registers smell musty every time the heat kicks on — is duct cleaning going to fix that?

That smell is the most common reason we get called in Mill Valley, and it usually starts under the house, not in the ducts themselves. On a shaded canyon lot with a vented crawlspace, the supply metal runs cold, picks up condensation, and the duct insulation around it never fully dries out. Cleaning removes the debris and surface growth that the odor feeds on, which helps. But if the wrap is saturated or the liner is degraded, cleaning alone is a temporary fix. We'll tell you straight when what you actually need is replacement of a run or better crawlspace conditions, rather than taking your money for a cleaning that smells the same in two months.

Our house is a 1920s cabin that's been added onto a few times. Does that complicate the job?

It changes how we approach it. Older Mill Valley cottages that grew room by room tend to have ductwork added in layers: a short original trunk, then long branch runs feeding the newer rooms, often different materials spliced together and routed through whatever space was available. We walk the under-house area first to map what's actually there before quoting or scheduling, because the floor plan upstairs rarely tells you how the ducts run below. Expect more access points and more hand work than a single-era house would need.

What makes a Mill Valley job cost more or less than average?

Access is the biggest factor here. Homes on posts and piers down a hillside, with a crawl opening you have to belly through, take longer than a house you can stand up under. Number of registers matters, and so does whether the runs are flex, old rigid metal, or a mix. Multiple additions mean multiple branch runs. On the other side, a lot of Mill Valley homes have no AC at all, so there's no air handler coil or cooling-side work in the scope, which keeps things simpler. We'd rather look under the house before putting a number on it than guess from the curb and revise on you later.

When's the best time of year to have this done?

Late spring through summer, once the heat has stopped running. Mill Valley systems are heating-dominant: they work October through May and then sit idle. Cleaning during that idle stretch means you're not without heat for an afternoon, the crawlspace is at its driest point of the year, and you start the next heating season clean instead of pushing a summer's worth of settled redwood duff and bay laurel debris through the house on the first cold night. Fall is also fine if you're already smelling something; we just book up more as the rain starts.

Can you come out same day if the smell suddenly got worse?

Sometimes, but it's not something to count on in Mill Valley. A sudden change in odor after a wet stretch often means water is getting somewhere it wasn't before, and that's worth looking at quickly. We can usually get someone out within a few days, faster if we have a cancellation. The limiting factor is often the house itself: narrow hillside driveways and tight crawl clearances mean we send the right crew and the right equipment rather than whoever is free in the next hour. Call and describe what changed and when; that tells us how urgent it is.