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Stages of Black Mold

Black mold does not grow just anywhere. In order for black mold to develop, certain environmental conditions must first be in place. If the conditions are right, mold starts to grow and eventually forms large colonies that are difficult and expensive to remove. Since black mold is a known health hazard, preventing the conditions for growth is a lot easier and cheaper than mold removal, which costs thousands.

  1. Environmental Factors

    • According to New Mexico State University and the Virginia Department of health, mold only grows in humid areas were the temperature is at least 65 degrees Fahrenheit. Stagnant air and low light levels also contribute to mold growth. A mold-friendly environment is created by a number of factors. Pinhole leaks in plumbing inside walls soak the walls. Minor roof leaks allow rain water to run down the inside of walls. When flood waters recede, walls act like a sponge, holding in water. All these factors create a warm, dark and damp environment.

    Depositing of Spores

    • Black mold spores circulate naturally in the air, as they are only one cell and are therefore extremely light. A spore is the equivalent of a seed in plants. When a spore hits a sunny surface with good air circulation, it does not grow. Mold also does not grow in extremely cold conditions. Inside warm, damp walls, it's a different story. The spore clings to the wall, and starts to multiply because of the environment. Any little crevice or crack, no matter how small, allows the tiny black mold spore to reach the inside of walls due to air currents carrying it. Mold spores also are present in rain or flood water. If water leaks inside a wall, it carries mold spores with it.

    Colony Formation

    • Since mold multiples rapidly, large colonies form. These areas coat walls and the associated framing lumber. In flooded out houses, a clear parting line is present where the water receded. The wall looks like it was spray painted black below the water line.

    Material Destruction

    • The food supply for black mold is wood and the trapped moisture in drywall is its water supply. The large black mold mats transform the wood into simpler compounds. The wood rots due to fungi eating the nutrients out of wood. According to William F. Lyon of the Ohio State University's Agricultural Extension Service, wood rot due to fungi happens to framing lumber, log cabins and wood trim. He further states that about 10 percent of new wood production in the United States is destined to replace rotted wood.

    Health Effects of Stachybotrys

    • According to the Mould Facts website, not all black molds cause health problems. Molds come in different colors, such as black, white, orange and blue. The site states that only one type of black mold, Stachybotrys, causes negative health consequences. Some white molds, however, are just as bad. The problem molds contain a toxin that acts as a respiratory irritant. Some people are immune to it while others develop severe ailments. These include flair-ups of asthma, wheezing, coughing, continuous sores, or a scratchy throat and watery eyes.

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