How Does Mold Grow?

Mold is an organism found in nature. It helps in the decomposition process of many organic matters. Mold is useful in the environment, but when mold invades out homes and we are confined with it, mold can cause human beings health problems. The good news is that if you eliminate the conditions that encourage mold growth, then mold does not have to be a health concern.

Types of Molds

There are many types of molds that can be found in the environment. Many types of mold can even co-exist together feeding in the same area, using the same organic food source. Some mold types are:

• Aspergillus ssp. – Most common mold in the environment


• Stachybotrys chatarum – Very toxic


• Cladosporium ssp. – Very commonly found indoors


• Penicillium spp. – Commonly found on decaying food matter

How Mold Grows

Mold is a living organism and like all living things, it requires some specific conditions to grow and thrive. These conditions include:

• Moisture – This can be caused by high humidity, steam from the bathroom or shower, or a leaky roof. If the moisture is allowed to collect and is not exposed to enough air to allow it to dry rapidly, then mold will begin to form and grow.


• Food – Mold needs a food source in order to grow. This food has to be organic in nature such as plant materials or wood or other natural materials. Our homes are routinely made out of materials that molds can use to feed on and thrive.


• Darkness – While darkness is not completely required to grow mold, it does encourage it to reproduce much more quickly than lighter or sunnier areas. The sun is warm and will inhibit mold growth by drying out the organic matter it is feeding on.