Air Duct Cleaning in Corte Madera, CA

Frequently Asked Questions

My floor registers have rust around the edges — is that coming from the ducts under the house?

Usually yes. In the older single-story tracts here, the supply runs sit in a crawlspace over filled marsh ground with a high water table, so the metal stays cool and damp most of the year. Moisture condenses on the duct and collects at the boots, which is where rust starts and then works up to the register face. Cleaning removes the debris that holds moisture against the metal, but if a boot is already rusted through or the duct body is soft, we'll tell you that straight and show you photos instead of vacuuming over it.

Why does dust puff out of the vents every time the furnace kicks on?

That's a common call we get in Corte Madera, and it's usually tied to the single central return these 1950s and 60s houses were built with. One return doing all the work means the filter loads fast and airflow is marginal, so fine dust settles inside the supply trunk between cycles and gets pushed out in one burst at startup. Cleaning the supply side and the return drop takes care of the blow-off. We'll also point out whether your filter slot is choking things further, since a too-restrictive filter on a single return makes the problem worse.

How soon can someone get out here?

Corte Madera is compact and flat, and we're routing through the 101 corridor between Larkspur and Mill Valley regularly, so most homes here get scheduled within a few days. If you're calling because of a musty smell or something visible at a register, say so when you book, since those move up. Townhomes and condos near the shopping corridor sometimes need an extra day if HOA notice or access to a shared mechanical area is involved.

What makes the price go up or down on a house like mine?

The biggest factor here is crawlspace conditions. A dry, accessible underfloor run on a ranch tract is straightforward. A low, damp crawlspace on the bayside flats, where we're working around standing moisture, tight clearance, and corroded boots, takes longer and costs more. Number of supply drops matters too, and the single-return layout common in the original tracts keeps the return side simple. Condos and townhomes near the shopping corridor generally have smaller systems with shorter runs. We quote after we've seen the crawlspace, not off a phone description, because the photos homeowners send rarely show how tight it actually is down there.

We get fog rolling in almost every summer night and barely run the AC — do our ducts even get dirty?

Different kind of dirty. Without much cooling load, you're not cycling a lot of air, so you don't build the heavy dust load you'd see in a hot inland town. What you get instead is humidity that never really drops, sitting on duct interiors in a crawlspace that's already damp from the marsh below. That's what leads to the musty smell at the registers and the biological growth we find on insulation and at boot connections. Low AC use doesn't protect ductwork here; the moisture drives the need, not the dust.