Mold can be expected in even the cleanest home. Mold is a fungus whose spores are always present in the air — millions of them. When conditions are right, these spores attach to an accommodating surface and form a colony. These colonies are commonly known as mold or mildew, terms we tend to use interchangeably. Mold takes on many colors. Shades of blue, green, black, brown, white, red or orange are normal. A musty smell in the house is also a sign that mold may be present.
Mold and mildew can be found (in, on or under) walls, floors, ductwork, attics, crawl spaces, gutters, ceiling tiles, houseplants, window frames and many other spots.
Leaky roofing or roofs where ice dams have intruded can harbor mold colonies. Today's energy-efficient homes are pretty airtight. When housing spaces aren't ventilated properly, moisture and stale air (two of mold spore's primary environmental triggers) can be trapped. But don't blame your home for the majority of mold cases. Mold can occur where three environmental triggers combine. When the correct temperature, food and moisture meet the right species of mold, it won't be long before a colony appears.
The environmental conditions present after natural disasters, such as floods and hurricanes, are notorious grounds for mold and mildew. The optimum temperature for mold to form depends on the fungus itself. Mold can be equally at home in a refrigerator or an attic, but warmer temperatures primarily trigger mold growth.
Mold feeds on organic matter, which can be found in drywall, insulation, fabric, leather, carpet and paint. Dirt and dust also provide nutrition for a mold colony. These food supplies can even rest on unsealed concrete block, shower curtains and glass. Moisture can take the form of liquid (rain or flood water) or vapor (a room's relative humidity). Moisture can also result from the capillary action of water being absorbed by porous materials, like wood, drywall, carpet and brick. Air can contain a lot of moisture and warmer air holds more moisture.
Several molds may be categorized as hazardous. Stachybotris, more commonly know as black mold, is a black / green-colored mold that occurs mainly on items containing cellulose. These items include paper, fiberboard and wallboard. In order for black mold to form, excessive moisture needs to be present. The catalyst therefore can be high humidity, leaks or other water damage. The space between walls and floors are ideal environments for mold to grow unnoticed. The problem may remain hidden from view for some time, creating a significant problem.