Air Duct Mold Removal in Chula Vista, CA

What mold removal in Chula Vista ductwork actually involves

The marine layer does most of the damage here. Cold supply plenums sweat in humid air. That moisture sits on galvanized metal and fiberglass liner. Growth follows. Homes closer to the bay see it earlier than inland East County. The August and September humidity surges make it worse, especially on under-insulated attic flex runs.

Mold in ducts is a moisture problem first. Scrubbing without finding the water source buys you months. We check the evaporator coil, the condensate pan, and the drain line before touching a register. A slow drain floods the pan and wets the plenum below. Undersized returns pulling air across a wet coil do the rest.

Bare sheet metal cleans well. Fiberglass duct board and the porous inner liner of flex duct do not. Growth roots into the fibers. Those sections get cut out and replaced, not fogged. Under-slab ducts in 1950s and 60s homes are the hard case: standing water, rust, silt, and no good way to keep them dry. Abandonment and overhead rerouting is often the honest answer.

Dark staining at a boot is sometimes just attic insulation fiber and ash. Worth confirming before anyone starts cutting.