We live in an older home that is raised a couple of feet off the ground with a crawlspace under it. In the past few years, the hardwood flooring in several rooms has started to warp and cup. What could be the problem?-Mary

Hi Mary,

It sounds like you may have excessive moisture and humidity in the crawlspace under your home. Here’s what you can do to correct it:

• Make sure the ground around your foundation slopes away from the house (1/2″ per foot or more).
• Divert rainwater run-off from the roof away from the foundation by installing gutters and extending the downspouts so water is diverted beyond the planting beds and out into the yard.
• Check your air conditioner unit to be sure the AC drain pipe isn’t clogged and extend it if needed to direct condensation water away from the foundation of your home.
• Inspect the crawlspace under your home. While the soil may be moist, it shouldn’t be saturated or have standing water.
• Look for any plumbing leaks as well as excessive dampness, mold, and mildew.
• If mold or mildew are present on the joists or bottom of the subfloor, treat under the house with a product such as Concrobium Mold Control (available at The Home Depot along with a fogger to rent).
• Clean out any debris and stored items under your house, and fill in any holes or depressions.
• Cover the entire crawlspace with thick, black plastic sheeting (6 mil or higher). Overlap the seams by a foot or more and run the plastic up the sides of the foundation.
• For extreme moisture problems, consider taping the seams in the plastic together, block the outside vents, and install a dehumidifier in the crawlspace to remove excess moisture from the air.Good luck with your project,

  

  Further Information

  • How to Stop Condensation in a Crawl Space (article)
  • How to Keep Wood Floors from Buckling and Cupping (article)
  • How to Reduce Mold and Moisture Under Your Home (video)
  • How to Insulate a Crawl Space Under Your Home (article)