Mold Needs Moisture: What EPA Says to Do About It at Home

You cannot remove every mold spore from a home, so EPA’s advice is about the thing mold needs.

EPA puts it this way: the key to mold control is moisture control. Every tip below is a way of keeping water and humidity from lingering.

EPA says to repair plumbing leaks and other water problems as soon as you find them, and to dry wet or damp items and areas within 24 to 48 hours. When damp materials are dried within that time, in most cases mold will not grow. That is a target, not a promise (EPA).

When the water was more than a damp spot, the drying is a job in itself. See structural drying and water damage restoration.

• Appliances that make moisture. EPA says to vent clothes dryers, stoves and kerosene heaters to the outdoors where possible (EPA).
• Bathrooms. Run the bathroom fan or open a window when showering (EPA).
• Kitchens. Use exhaust fans or open windows when cooking or running the dishwasher (EPA).

EPA suggests keeping indoor relative humidity below 60 percent, ideally between 30 and 50 percent. An inexpensive moisture or humidity meter, sold at many hardware stores, can measure it, and air conditioners or dehumidifiers can be used when needed (EPA).

EPA says condensation on windows, pipes or walls can signal high humidity. Dry the wet surface quickly and reduce the source of moisture, increase airflow by opening doors or windows when practical or using fans, insulate cold surfaces such as cold water pipes, and raise the air temperature (EPA).

Keep air conditioner drip pans clean and drain lines unobstructed, so water flows properly (EPA).

EPA says to clean and repair roof gutters regularly, and to grade the ground so it slopes away from the foundation, keeping water from collecting near it (EPA).

If you already see or suspect mold, see hidden mold and cleaning up mold.

H&H Environmental has operated since 2005. On a New York mold project, H&H performs either the mold assessment or the mold remediation — never both on the same project. See mold services.

H&H is based in Saugerties, in Ulster County, and focuses on eight New York counties. Call and tell us where the property is and what has happened, and we will confirm availability.