Preventing & Ridding Your Home of Mildew

— Written By Trudy Pickett and last updated by

Mildew can be found on many different surfaces. It is a thin, black, or sometimes white, growth produced by mold. Molds are simple plants belonging to the group known as fungi. Though molds are always present in the air, those that cause mildew need moisture and certain temperatures to grow. They commonly develop in humid summer weather, especially in closed houses, but can form any time of the year.

Mold spores are present in the air and may settle onto surfaces if there is sufficient moisture. Molds grow on anything from which they can get enough food. In homes they develop most often on cotton, linen, rayon, silk, wool, leather, wood and paper. Many synthetic fibers resist mildew.

Molds that cause mildew flourish wherever it is damp, warm, poorly lighted and/or where air is not circulated — in cellars, crawl spaces of houses without basements and clothing closets. It can also be found on draperies and rugs in basement recreation rooms, on shower curtains and on damp clothes rolled up for ironing. These molds are also likely to grow in a new house because of moisture in the new building materials.

As the molds grow, they cause considerable damage. They leave a musty odor; they discolor fabrics; and sometimes they eat into them until the fabrics rot and fall to pieces. They also discolor leather and paper.

To prevent mold and mildew,keep closets, dresser drawers, basements — any place where mildew is likely to grow — as clean as possible. Soil on dirty articles can supply enough food for mildew to start growing when moisture and temperature are right. Greasy films, such as those that form on kitchen walls, also contain many nutrients on which mildew-causing molds feed.

Clean clothing is less likely to mildew than soiled clothing. Because most synthetic fibers, such as acetate, acrylic, polyester and nylon, are resistant to mildew, clean fabrics of these fibers will not support mold growth. But even on these fabrics, soil may supply food to start mildew. Clean all soiled fabrics thoroughly, regardless of fiber type to help prevent them from mildewing.

A damp basement, or any other structure, is often caused by moisture condensation from humid air settling onto cooler surfaces. Excessive moisture may indicate that repairs or additional insulation are needed. Replace cracked or defective mortar in masonry surfaces. Some basements are continually wet from water leaking through crevices in the wall. Make sure outside drainage is adequate. For waterproofing concrete and other masonry walls above ground, apply two coats of cement paint. Waterproofed coatings to seal absorbent brick and other outside surfaces may be needed.

Spread a layer of moisture-barrier material over the soil in crawl spaces under houses. Heavy polyethylene plastic film works well as a moisture barrier in crawl spaces. Good ventilation is important. In extreme cases, a fan or blower may be needed to move the humid air from under the building. Crawl space dehumidifiers can also provide moisture control.

In the laundry room, exhausting the clothes dryer to the outside is necessary to direct moist warm air away from the interior of your home. In bathrooms and kitchens use exhaust fans to pull moist air out of the home.

Next week: Part 2: Preventing and Ridding Your Home of Mildew

Source: University of Missouri