The answer to 'air duct mildew' is that mold and mildew growth in air ducts is a common problem that can pose health risks and reduce the efficiency of your HVAC system. Mold thrives in damp, dark environments, and can grow on the interior surfaces of air ducts if there is excess moisture or poor ventilation.
Common causes of air duct mildew include leaks in the ductwork, high humidity levels, and improper maintenance. Symptoms may include musty odors, visible mold growth, and respiratory issues for occupants. To address the problem, it's important to identify and fix the underlying moisture issue, then thoroughly clean and disinfect the affected air ducts.