Wet Basement Problems

Condensation May Be the Cause

• If dampness is a persistent problem, and not one that occurs after a rainstorm, you might be dealing with condensation instead of water leakage. This is especially true if it occurs during hot weather. To determine whether condensation really is the issue, tape a square of plastic wrap to the wall in an area of the basement where dampness has previously appeared. Seal the edges of the wrap securely and leave it for a few days. Moisture on the open side of the wrap indicates a condensation problem.

Dealing with Condensation

• Remove potential sources of moisture in or near the basement, including indoor clotheslines, and ensure that the dryer's exhaust vent doesn't leak or vent exhaust indoors. Leaky plumbing elsewhere can cause basement condensation; check the integrity of pipes in the ceiling.

  Exhaust fans remove damp air and increase air circulation to prevent the problem from reoccurring. You can also improve air circulation in a crowded basement by clearing out junk or unused items to create more air flow. Insulating exposed pipes or ductwork can also reduce condensation.

Problems Due to Seepage

• One common cause for a wet basement is when rainwater or snowmelt is diverted to the house instead of away from it. The moisture seeps through topsoil, which is porous, and is forced through the compacted soil near a house's foundation and any cracks or gaps in the walls by hydrostatic pressure and capillary action. If a basement becomes damp right after a storm or snowmelt, then the problem is due to seepage, and not condensation.

Dealing with Seepage

• The ground around the house should be regraded to draw water away from the foundations. Soil around the foundation should slope away at 1 inch per foot up to 4 feet. Gutters may need cleaning and patios and walks may need reshaping to direct water away from the house. If needed, add downspouts so that gutters can drain 4 feet away from the house. Inspect the basement walls themselves and caulk to seal out any surface water seepage. Most people install a sump pump system as well.

Obtaining Professional Advice

• If basement wetness is persistent and abundant, then the problem may be high groundwater. After determining this with the local municipality, engage a home inspector or engineer specializing in such problems. For a modest fee, they can pinpoint a problem accurately and suggest a cost-effective and permanent solution, which can save you a lot of money. An alternative would be to consult a waterproofing company directly, but their solutions are often costly and may not address the problem adequately.