HVAC Duct Cleaning in San Rafael, CA

Why San Rafael ducts load up in the first place

Most of it starts under the house. Pre-1940 Marin homes run sheet metal trunks through a vented crawlspace. That space is damp and open, and rodents get in. Boots drop off the subfloor. Flex tears at the takeoff. Then the return pulls crawlspace air straight into the house. In Ross Valley and the hillside streets, nesting and droppings in the trunk are routine, not rare.

The second source is seasonal. Foggy mornings put condensation on cold supply lines, soaking insulation and giving you that musty smell at startup. Smoke events in late summer and fall load filters and settle fine particulate in the supply runs. Spring brings oak and grass pollen through leaky returns. Long dirt driveways add dry-season dust year after year.

Cleaning means source removal under negative air, not a shop vac at the register. Trunks and branches get brushed or air-whipped line by line. Registers and boots come off and get washed. Blower wheel and coil need access, since that is where the film collects.

Open boots get reconnected and sealed. Filter slot sizing and return path get corrected. If the ducts are crushed flex or rodent-packed throughout, replacement beats cleaning, and we will say so.