When high levels of mold are found indoors they can cause allergies, trigger asthma attacks in sensitive individuals and even lead to infections in some people. In order to grow indoors, mold needs moisture and food.
Moisture is a key factor influencing mold growth indoors and controlling indoor moisture can dramatically help to limit its growth. Moisture control is crucial as mold can begin to grow indoors in as short as 24 to 48 hours when conditions are right.
Mold does not need a lot of water to grow. A little condensation, in a bathroom or around a window sill, for example, can be enough. Common sites for indoor mold growth include bathroom tile and grout, basement walls, and areas around windows, near leaky plumbing, and around sinks. Common sources of water or moisture include roof leaks, condensation due to high humidity or cold spots in a building, slow leaks in plumbing fixtures, humidification systems, sprinkler systems, and floods.
Besides moisture, mold also needs nutrients, or food, to grow. Mold can grow on virtually any organic substance. Most buildings are full of organic materials that mold can use as food, including many building materials and household furnishings. In most cases, temperature is not a major issue as some molds grow in warm areas while others prefer cool locations. Quite often, more than one type of mold can be found growing in the same area, although conditions such as moisture, light, and temperature may favor one species of mold over others.
Buildings that have been heavily damaged by flood waters should be assessed for structural integrity and remediated by experienced professionals. Flood waters can also contain bacteria, viruses, and a wide variety of chemical contaminants.