More on Mildew – The Basement Is Damp

Dear Home Ec 101,

When I am in the basement, my allergies kick in, immediately, with all the typical allergy symptoms! It may be associated with dampness in an 1880’s basement. We keep it very clean, and no moisture seems to be present, except on a wall or two in which the paint is affected.

Signed,
Sneezing in Snelling

Heather says:

Allergies are no fun. As an aside for your overall health, I highly recommend getting tested to know exactly what is triggering the attacks. Is it dust mites or mold / mildew? (Granted some of the things I am about to go over will help no matter the cause, it’s just good information to have)

To make this information more helpful for the Home-Ec 101 audience, I’m going to answer it as though you hadn’t begun looking for water damage.

Humidity enters your home through four pathways:

  • rain water or plumbing leaks
  • capillary action – your building materials absorbing water from the ground. You’ve seen capillary action every time you’ve used a paper towel to mop up a spill
  • diffusion – water vapor molecules moving through your building from the outside (high concentration) to the inside (lower)
  • air transport – pretty obvious – windows, doors, vents etc

In a basement you’re most likely to see the first three, unless the basement is a walkout and in that instance, air transport can play a role.

Not seeing moisture damage doesn’t mean it isn’t occurring. Invest ten bucks or so in a hygrometer.  HygrometerIf your basement’s humidity level is more than sixty percent, it’s time to take steps to mitigate the problem.

Why sixty percent? This is the point at which our little microscopic friends begin thriving. What happens when organisms thrive? They multiply. Fun.

What can you do to reduce humidity in your basement?

First ensure that all gutters direct water at least a few feet away from your foundation.

Next, look for moisture damage and ensure there aren’t any plumbing leaks, if so have those fixed and ensure that none of the dry wall or insulation has turned into a mold factory

If your basement is unfinished, with dirt floors, install a vapor barrier –plastic sheeting– to do just that.

If it’s a minor, seasonal problem a product like DampRid can be useful, just make sure that the canister you buy is adequate for the square footage.

Danby PremiereIf the humidity problem is more than just during the spring, consider investing in a dehumidifier. Pictured to the right is one I have. As most of you know by now, I live in the South. I also have an older home and rather than crank the AC, I turn on the dehumidifier as lower humidity makes higher temperatures more comfortable (When you sweat it actually evaporates instead of just making you feel gross.) If you have a utility sink you can drain directly into that rather than fussing with the reservoir.

Once the humidity can be maintained below sixty percent, it’s time to thoroughly clean the basement. Don’t forget, if your washer is in the basement, to check it for mildew, too.

Good luck and feel better.

Submit your questions to helpme@home-ec101.com.





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