Wet Weather Could Mean Mold – Prevention and Remediation of Mold Growth in Office Buildings

Fall is upon us, bringing beautiful leaves, cooler weather, and rain. While mold growth can happen at any time of the year due to a water leak or other source of intrusion, fall weather often exposes any new leaks or structural failures. This moisture intrusion can lead to mold growth.

Mold growth fundamentally occurs in the presence of moisture. Basic maintenance can prevent the development of mold by preventing leaks before they can occur and maintaining relative humidity levels below 60 percent. The ideal spectrum is 50-30 percent.

Sometimes, though, a leak goes unnoticed. When the heat is turned on in the autumn, mold “blooms,” showing discoloration where none was detected before, or a roof system can fail, allowing sudden water intrusion.

Odor and Discoloration

If odor, discoloration, or sudden water intrusion is noticed, begin remediation immediately. Industrial hygienists can help identify less apparent water intrusion using moisture meters and determine the type of suspected mold growth through air and surface sampling.


In cases of sudden water intrusion from a leak or other source, efforts should be made immediately to remediate the leak and dry impacted materials. As a rule, permeable surfaces that can not be dried within 48 hours, such as wallboard, should be removed to prevent mold growth and to maintain structural integrity.

Small amounts of mold growth may be remediated in house, but when suspect visible mold growth is found exceeding 10 square feet, special precautions must be taken. In these situations, a remediation contractor can establish containment of the area to prevent the airborne spread of mold, and workers will have the training and personal protective equipment needed to stay safe.

Locating the Source

As moisture is the fundamental element of mold growth, the source of moisture intrusion must be located in order to prevent recurrence. Industrial hygienists can offer mold and moisture assessments that help locate the source of intrusion and offer recommendations on remediation, or they can work directly with the remediation contractor to ensure the best outcome.