Hidden Mold

Using clichés should always involve second thoughts. But you know, phrases become clichés because they’re usually true, and, yes, an ounce of prevention is worth a pound of cure. What better place to apply that ounce than the health of your family?

There are sections of your house you will never see, or likely even think about. Your attic, the spaces within and between walls and floors, and crawl spaces. The focus today is crawl spaces, which are basically squatty basements without a floor. Damp air flows down to crawl spaces while moisture comes up from the bare soil. Even with ventilation ports the air in crawl spaces is typically damp. That air is also musty. When you notice a musty smell, you’re smelling mold. You might even be inhaling mold, mold that can lead to allergies and additional health problems. The picture above is of active mold on sub-floor and joists in a crawlspace.

The Lowdown on Mold

Mold requires three common components – moisture, moderate or higher temperatures, and something organic to chomp on, like the joists, 2x4s and subfloors in your crawlspace. Mold produces a byproduct called mycotoxin, which has the potential to cause disease, neurological problems and even death in humans and animals. In all seriousness, mold is not a problem to just shrug off. Symptoms of mold exposure include chronic sneezing, coughing, runny nose and worsening of asthma. Homeowners can take basic steps to prevent the moisture necessary for mold growth.

In summer Louisville and the Ohio Valley have humidity levels approaching the subtropical. Even when using your air conditioner you should run a dehumidifier in your basement. Typically there’s an opening from the actual basement into crawlspaces, so the drier the basement the drier the crawlspace. In the middle of summer it’s not unusual for a dehumidifier to pull fifteen quarts of water, or even more, from the basement air per day.

Make sure your gutters are clean and not overflowing, and make sure the water from the downspouts is taken away from the foundation. Take advantage of slopes away from your house. If your yard is flat connect 4” drainage tubes to your downspouts and bury them running six feet out. You don’t need a slope, just keep the tubes level, leaving a small hole in the soil at the end of the tube. The pressure of the downward flow will push the water out the ends. Some crawl spaces have vents that open and close automatically. Make sure these vents are working.

Finally, a word about air conditioning. All air conditioners remove moisture from the air. That’s why there’s a puddle under your car after being parked for a while. Drier air feels cooler. If you ask your HVAC guy he’ll tell you the best, and least expensive, way to use your system is to turn it on at the beginning of hot weather and leave it on. Find a temperature you can live with, then set the thermostat and forget it.
Opening windows at night brings in moisture-laden air, which your system will spend hours removing when turned on the next day. This is especially true with heat pump systems. Using your air conditioning system all summer goes a long way in preventing moisture that eventually flows down to the lowest levels, your basement and crawlspaces.

Next time —You’ve got mold. Now what?