Treatments for Air Duct Mold

Mold has become a great concern in home environments, as more cases are being reported by residents of structures that reveal previously undetected mold growth in walls, sub floors and attics.

Cleaning of Air Ducts

This phenomenal increase in mold infestations in houses, apartments and even commercial properties (known as “sick building” syndrome) is often the result of the spreading of live mold spores by infested HVAC systems, and treatment of the air duct mold is always the focus of remediation in these situations.

The process of mold growth in air ducts is considered to be directly related to the accumulation of dust and debris in duct systems. New air ducts that are free of any interior surface debris, regardless of the material they are made of, will become vulnerable to mold growth once airborne dust, fibers from upholstery and clothing, and human and pet hair have a chance to collect inside the air ducts. This buildup of debris will catch any moisture in the recycled air along with any mold spores that are introduced into the interior environment of the building. These conditions will invite and accelerate mold growth.

Cleaning the duct system is recommended as a step in the treatment of air duct mold, unless conditions require replacement of all the air ducts. The cleaning process involves high-efficiency particle arresting (HEPA) vacuums to remove debris from the environment and brushing and contact-vacuuming of the air ducts and vents as well as all other components of the HVAC system.

Chemical Treatment of Air Ducts

The application of fungicides is the suggested method for chemical treatment of air duct mold. Fogging and misting of sealed interior environments with a fungicide, along with a similar treatment of the entire HVAC system, is recognized by the EPA and mold remediation contractors as an effective way to rid a structure of mold. It is also recommended that all items in the interior (including furnishings, clothing and other items not associated with food preparation or storage) be treated. This is accomplished either by first removing them from the structure to provide an obstacle-free treatment of the interior areas and then returning them for a second treatment, or by leaving them within the structure for inclusion in the treatment.

Replacement of Air Ducts

One of the problems with treatment of air duct mold is reaching all surfaces within the duct system with the fungicide, biocide or other chosen mold treatment formula. One of the more problematic types of air duct materials, according to the EPA and air duct and insulation experts, is fiberglass. Fiberglass ducts or ducts lined with fiberglass have been found to be more susceptible to mold growth because of the porous nature of the material. In some cases, replacing the air ducts may be the only reliable solution, especially when long-standing mold infestations have had a chance to saturate and take over all interior surfaces of the duct system. This can be a costly procedure, yet this solution has been recommended by mold remediation contractors in severe cases. This procedure will, of course, be accompanied by a full mold remediation of the infested structure and any correction of moisture problems that are contributing to the mold problem.

About the Author

Greg Jackson is a transcriber, proofreader and editor. Jackson has been writing professionally since 1975, drawing on creative writing courses and personal experiences. His most outstanding work has been as an editor, proofreader and transcriber on two published books, "Douglas Fairbanks: In His Own Words" and "Bohemian Grove: Cult of Conspiracy."