Ask An Expert: Minimize Mold Risk After Wet Weather

Ask an Expert is an occasional feature where we pose a question submitted by readers to our Healthy Building Scientist Joe Medosch.

Reader Question: I know that moisture and mold go together. What can I do when it is so wet outdoors?

Rainy and snowy days now often mean moldy days later. Some molds can take up to 30 days to develop, so minimizing risk means doing more than just quickly fixing leaks and drying damp spots while it is wet outside.

There are many myths about mold, but one thing is for sure, mold thrives in damp environments. Here are two common scenarios for moisture and mold growth:

Moisture and Mold in Warm Climates

In warm/humid climates like Florida, Georgia, and Alabama or marine climates like Oregon or the California coast, extended periods of wet weather are followed by warm day and moisture accumulates. But it doesn’t get warm enough for long enough to really dry out the house, especially within exterior walls. The result: damp spaces where mold can bloom in the following days and weeks.

Moisture and Mold in Cold Climates

In cold/dry climates like Minnesota, Michigan, and New York and moisture issues tend to come from inside the house. Sealed up tight against the cold, moisture from everyday activities like showering, cooking, and laundry tend to accumulate in the house. With long periods of cold temperatures and low ventilation, dampness can linger and mold can follow. Cold climates can also see large amounts of snow pile up against the house and then melt leaving behind wet exterior walls and damp interior wall cavities where mold can grow.

What can you do?

Mold removal methods must be effective at removing the mold, safe for the occupants of the house, and not cause unintended consequences later. Chemical sprays and other mold treatments do not meet these criteria. Here’s what you can do:

For more information on how you can deal with moisture and mold at home after wet weather, read our blog here on four actions to stop unknowingly growing mold in your home. To learn more about toxic mold, read our blog on the truths (and myths) of black toxic mold. You can also visit the EPA’s guide to Moisture and Mold in Your Home.

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Getting to a healthy home can seem daunting, but it is possible and our experts are here to help! You can Ask an Expert, and one of our Hayward Score team members will contact you within 2 working days to schedule your call.

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