Air Vent Cleaning in San Rafael, CA

What air vent cleaning actually fixes in San Rafael homes

A disconnected boot under the house is the real cost. That supply dumps conditioned air into the crawlspace. You pay to heat vented dirt. The return side then pulls crawl air upstairs: rodent droppings, damp soil odor, insulation fiber. In Ross Valley and the hillside streets, rodent nesting in trunk lines is routine, not rare. Waiting a season turns a sealing job into a contamination job.

Pre-1940 Marin houses are the hard ones. Gravity furnaces got converted to forced air. Sheet metal trunks sit in the crawlspace, joints wrapped in cloth or asbestos-era tape. Usually one undersized central return. We do not brush unknown wrapped joints. Those get tested or left alone.

Different stock, different failure. 1950s-60s ranch tracts hide runs in low attics with floor registers that collect everything dropped on them. Eichler-type slab homes had no ducts at all, so the retrofit flex lives in the attic or a soffit chase, with crushed sections at the turns. Condos push dryer lint and kitchen grease between units.

Real cleaning means source removal. Negative-air vacuum at the plenum, then brush and air-whip each branch. Registers and boots pulled. Blower wheel and coil checked. Smoke-season particulate sits in supply runs long after the air clears outside.