How To: Prevent Mold and Mildew

Molds can grow on virtually anything around the house — from wood, carpet and food to insulation systems in your walls. Follow these guidelines to rid your home of pesky mold and mildew.

By Michelle Roberts | Updated Mar 9, 2021 3:18 PM

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Prevent Mold and Mildew


Mold is more prevalent today because the focus on improving energy efficiency resulted in more airtight homes that don’t breathe as well as older structures and more complex home designs have increased the potential for moisture intrusion, according to Responsible Solutions to Mold Coalition.

Homeowners have become increasingly concerned about the indoor air quality of their homes as Americans spend around 90 percent of their time indoors, according to the National Center for Healthy Housing. The Asthma and Allergy Foundationsays that one out of four are affected by asthma and allergies, and the main agents are dust, mold, and mildew.

About Mold and Mildew
Molds can grow on virtually anything around the house — from wood, carpet and food to insulation systems in your walls. Mold typically grows where there’s excessive moisture, like in a damp cabinet under the sink or around a leaky window, so it’s important to ventilate these areas and prevent moisture from accumulating.

It’s also critical to prevent mold from intruding your home. Mold usually forms by water or mildew entering though vents and heating and cooling systems and then latching onto the walls of a tightly sealed bathroom with little or no ventilation. Keeping these places well-maintained and aired out will help prevent mold from taking hold.

Myths and Realities
Responsible Solutions to Mold Coalition, a Chicago-based collaboration of 16 companies, associations, and government and academic organizations, has compiled a list of mold characteristics and ways to, prevent the fungus from infiltrating your home:

Myth #1: Mold grows only on paper, wood, and other organic material
Mold will grow on any surface. Even flat and smooth surfaces like glass, fiberglass, and steel are mold-susceptible. As long as mold spores (which are always in the air), moisture, and particulate matter (like dust) are prevalent, mold can grow. The only effective strategy to control mold is to control moisture, like installing dehumidifiers and fans in basements and kitchens.

Rebecca Morley, the Executive Director of the National Center for Healthy Housing, recommends removing all moldy materials and replacing them with highly durable mold- and mildew-resistant materials in the tub/shower enclosure after leaks or other sources of moisture are fixed.

Myth #2: Water intrusion is inevitable
Homeowners can easily prevent water intrusion by staying vigilant of any leaks around the house, especially in bathroom faucets, showers and toilets. Building experts urge homeowners to stay alert for signs of mold, including dampness, odors, discoloration, peeling paint, condensation, compacted insulation and actual mold outbreaks. New York’s Department of Health says to be on the lookout for slightly furry, discolored, or slimy patches that grow over a period of time.

Myth #3: Mold is the only problem associated with water and mildew intrusion
Water and mildew intrusion is like opening Pandora’s box. Mold, insects, and other pests love damp environments. Dampness can also severely damage essential building materials, such as your home’s foundation, so make sure you find where the water and mildew are entering and find measures to prevent it.

If your building materials are already damp or mold-infested, replace them with dry alternatives immediately. USG’s SHEETROCK and MOLD TOUGH gypsum panels are made with mold inhibitors on the paper facing, on the paper backing, and in the core. DUROCK, USG’s cement board is water-resistant, which prevents mold accumulation, and is easy to install. Dan Collins, Senior Manager at USG, recommends using MOLD TOUGH in lieu of standard sheetrock and green board in basements, kitchens and baths.