What Causes Mold? It Could Be Your Damp, Leaky Basement


Mold is a fuzzy growth on moist organic matter. When mold spores land on surfaces that are wet or damp, mold may begin to grow. There are many types and colors of mold, and none of them will grow without water or moisture. Mildew is mold. It's a word that is used generally to refer to a few specific types of molds, but it's still all molds.

A lot of people aren't aware that mold can be white, orange, blue, grey, brown or black. Black mold is the most common color people know about. The type of black mold associated with ill health effects is called Stachybotrys (pronounced "stack-ee-bot-riss"). The color of a mold generally has to do with the spores it produces and has no bearing on whether it is dangerous or not. For example, there are some white molds that grow on walls and other surfaces that can be just as bad as some harmful black molds.

Another misconception is that bleach will get rid of mold. Bleach is generally not recommended as a fungicide (mold killer). Bleach is generally a water-based solution. Bleach appears to kill the mold, but because bleach is a water-based solution, this often means that water penetrated the surface giving moisture to the roots of the mold; which over time the mold happily begins to grow again.

There is also a myth that you can just paint over the mold. Actually, mold can eat the paint. Many people attempt to paint over mold only to discover that in a few months the mold has either poked its way through the paint, or the paint has started peeling off. The mold really has to be removed before painting can be done, even if you're using "mold-resistant" paint.

Mold is able to grow because it has a moisture source. Often this means that there is or was a leak or something similar involved in the first place. Just removing the mold without fixing the water problem will usually result in the mold coming back.

Molds gradually destroy the things they grow on. You can prevent damage to your home and furnishings, save money, and avoid potential health problems by controlling moisture and eliminating mold growth. Fix any water or moisture problems and use a dehumidifier in your basement to keep relative humidity below 60% (Ideally between 30 and 50 percent relative humidity).

First line of defense to keep your basement dry

  • Clean and repair roof gutters
  • Make sure ground slopes away from building foundation
  • Keep humidity below 60% (ideally between 30 and 50 percent)
  • Act quickly with water leaks (if wet or damp materials are dried 24 - 48 hours after an issue, in most cases mold will not grow)

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