The Risk of Mould Growth After Building Shutdown

After months of being closed up, buildings across the country are beginning to re-open as people return to work. These structures, which are normally in constant use, have been closed off and shutdown for months and could now be a breeding ground for mould. The tightness of construction for energy efficiency, the lack of fresh air, and our reliance on air conditioning have made buildings prone to becoming petri dishes when the controls are shut down.  

Mould can grow on a variety of surfaces, such as ceiling tiles, wallpaper, insulation, drywall, carpet, and fabric. In stagnant conditions, mould spores can easily find an adequate food source of organic materials such as dust and with air conditioners off and humidity levels rising, mould growth can occur.

People with asthma and other respiratory conditions and those with mould allergies or weakened immune systems should avoid buildings suspected or confirmed to have mould contamination. To ensure that your building does not have mould after a prolonged shutdown follow these five tips:

  1. Do a thorough cleaning, including all horizontal surfaces. Areas where dust has settled, like door jambs, the top of bookcases, even chair-rails and baseboards, are often neglected. Care should be taken to make sure every surface has been wiped down.
  2. Make sure the refrigerator is cleaned out and any food left out is removed and disposed of.
  3. If possible, open windows to allow fresh air to come in. The natural sunlight and fresh air are great oxidizers of microbial contaminants like mould, bacteria, and viruses.
  4. Maintain indoor humidity as low as possible, not exceeding 50%, as measured by a humidistat. If your system does not have a humidistat, use the thermostat and set the temperature at 27ÀöC which will cause it to run periodically throughout the closedown to maintain a dry environment.
  5. The building's HVAC system that has not been active during a prolonged shutdown should be operated for at least 48 to 72 hours (known as a “flush out” period) before occupants return.

Should you detect the presence of mould, contact ServiceMaster Restore for a professional assessment. Our technicians are trained in evaluating the various types of mould and the proper removal process.

With a little attention to detail and an awareness of the potential problem, you can be sure that you and your employees are moving back into a safe and healthy environment.