Common Molds Found in Commercial Buildings


Humidity and temperature regulation in commercial spaces is essential for maintaining the integrity of the structure and for keeping a normal indoor air quality. Without such measures, mold and mildew can tank air quality and could cause damage to your equipment and building, as well as the health of your staff.

According to the CDC, the three most common molds found indoors are stachybotrys chartarum, cladosporium, penicillium, aspergillus, and alternaria. While you should take preventive measures to stop the growth of mold in your building, it’s also wise to understand how these bacteria could affect your business.

molds culture

Mold Growth and Human Health

Exposure to common indoor molds, such as those listed above, has been linked to upper respiratory tract symptoms in generally healthy people, which is why mold is such a serious concern. Coughing and wheezing are common symptoms in those exposed, but for those with hypersensitivities or asthma, common mold exposure could cause pneumonitis or asthma.

Children and the elderly in particular are highly susceptible to the negative effects of indoor mold exposure and can develop respiratory illnesses that could be life threatening. Those with chronic respiratory disease or chronic obstructive pulmonary disorder could have trouble breathing from a simple common indoor mold exposure.

Where do these common molds come from?

Just like in residential environments, common molds in commercial spaces get in by a variety of means. Mold spores occur naturally in both indoor and outdoor environments, which can make it difficult to track the source of a problem in commercial applications.

Generally, mold spores get into the commercial space through the ventilation system, heating and cooling mechanisms, windows, and doorways. They also get in by attaching to people, clothing, shoes, bags, computers, and animals. But that’s just how they get in; how do they thrive and become a problem?

The real issue with mold isn’t its existence, but its persistence and growth. Mold loves areas with high humidity, especially in areas where there is already a leak, condensation, or persistent wet areas. Commercial spaces with relative humidity over 60% provide excellent conditions for mold growth.

How to Prevent Common Molds in Commercial Buildings

To prevent the growth of common molds in commercial buildings including stachybotrys chartarum, cladosporium, penicillium, aspergillus, and alternaria, there are a few steps we recommend.

  1. Clean up the mold. If you find mold in your commercial building, the first step you should take is to clean it up thoroughly with a bleach solution of 1 cup bleach for 1 gallon of water. Paper-based and porous building materials may need to be discarded if they’re affected, but other materials can be saved with thorough cleaning.
  2. Prevent new mold entry. After cleaning up an old mold problem, the next step is to prevent a new one from starting. We recommend sealing points of entry including doorjambs and windows, as well as duct work.
  3. Prevent mold growth. Finally, you need to take preventive measures to stifle the growth of mold by taking away what it loves most: moisture. With a commercial dehumidifier from Quest, you can lower the relative humidity of your commercial building and stop common mold growth in its tracks.