I have black, brown, red, white, or green stains or crystals on my unpainted block walls. Is it mold?

4/4/2017 (Permalink)

As we stated in an earlier post, you really can’t be sure if it is or isn’t mold without a lab report. However, most of the time these crystals and stains are efflorescence caused by water entering the block from outside the home, evaporating, and leaving the minerals and salts behind as crystals and stains. Although mold can grow on bio-films, dirt, or paint on block walls, it cannot grow on the concrete itself. Mold requires organic material to digest and concrete is inorganic.

A bigger problem with seeing the efflorescence on the block is the water intrusion itself. The water will evaporate from the block and condense on some other surface when it reaches the dew point. Unless this water is removed (usually by setting a dehumidifier) or prevented from entering the structure, the possibility of mold growth on other surfaces is likely. While SERVPRO of Manistee, Ludington, and Cadillac does not specialize in waterproofing basement, we can give you advice on keeping the water away from the structure.

Installing roof eves with downspouts that get the water at least 6 feet away from the basement is usually the quickest and most cost effective way to solve the water intrusion problem. Landscaping to divert the water away from the basement is another solution. The mold expensive (and sometimes necessary fix) is to dig up the wall and coat the outside with waterproofing material or install drain tile to remove the water. Sometimes installing a vapor barrio near the surface can help in preventing the water from causing problems. Give SERVPRO of Manistee, Ludington, and Cadillac a call at 877-723-4872.