What Is Mold

Mold (fungi) is present everywhere – indoors and outdoors. There are more than 100,000 species of mold.

Mold frequently grows in hidden places – behind wall linings, in floors or behind installations – and is often not visible from the outside. When moisture builds up from leaky pipes or roofs, high humidity, or flooding, conditions are ideal for mold growth. Molds are easily disturbed and their spores can become airborne, getting into noses, mouths and lungs.

Homeowner Tips

From the U.S. EPA Website

  • Moisture control is the key to mold control, so when water leaks or spills occur indoors – ACT QUICKLY. If wet or damp materials or areas are dried 24-48 hours after a leak or spill happens, in most cases mold will not grow.
  • Clean and repair roof gutters regularly.
  • Make sure the ground slopes away from the building foundation, so that water does not enter or collect around the foundation.
  • Keep air conditioning drip pans clean and the drain lines unobstructed and flowing properly.
  • Keep indoor humidity low. If possible, keep indoor humidity below 60 percent (ideally between 30 and 50 percent) relative humidity. Relative humidity can be measured with a moisture or humidity meter, a small, inexpensive ($10-$50) instrument available at many hardware stores.
  • If you see condensation or moisture collecting on windows, walls or pipes ACT QUICKLY to dry the wet surface and reduce the moisture/water source. Condensation can be a sign of high humidity.
Actions that will help to reduce humidity
  • Vent appliances that produce moisture, such as clothes dryers, stoves, and kerosene heaters to the outside where possible. (Combustion appliances such as stoves and kerosene heaters produce water vapor and will increase the humidity unless vented to the outside.)
  • Use air conditioners and/or de-humidifiers when needed.
  • Run the bathroom fan or open the window when showering. Use exhaust fans or open windows whenever cooking, running the dishwasher or dishwashing, etc.
Actions that will help prevent condensation
  • Reduce the humidity (see above).
  • Increase ventilation or air movement by opening doors and/or windows, when practical. Use fans as needed.
  • Cover cold surfaces, such as cold water pipes, with insulation.
  • Increase air temperature.

Additional Resources

  • Mold in Schools Resource List.  National Clearinghouse for Educational Facilities (NCEF) – Annotated list of links, books, and journal articles about identifying, assessing, and removing mold-contaminated materials from school facilities and preventing mold growth.
  • John Hopkins – Mold Control in the Home.  A useful interactive map of a home with tips on controlling moisture and humidity.
  • Mold In Our Homes.  A video resource for information about what mold is, what to look for, how to prevent it, and what options are available if you suspect mold in your home.
  • Mortgage Savings Program.   A bi-weekly mortgage and debt reduction company.
  • I-love-dogs.com.  Directory of Dog Websites & Tons of FREE Dog Stuff!
  • National Association of Mold Professionals (NAMP).  A non-profit organization that was established with the goal of developing and promoting the Mold Inspection and Remediation industry.