It's raining out and you have the sinking feeling it won't be long before water seeps into your basement. Or maybe you are just tired of the damp smell every time you go downstairs to your basement...or the kids refuse to play there because it "stinks". It is time to wade in and discover the cause of the water infiltration and how to fix it.
First, look at where the water is coming from. Is it condensation from moisture already in the basement or is it water seeping through the foundation? To determine which of these is your problem, wipe a section of the wet wall dry and tape a large sheet of aluminum foil to the wall. Wait a couple of days and then check the foil.
If there is water only on the room-facing side of the foil, you have a condensation problem. This means that moist air within the home and more specifically within the basement, meets the cooler wall and condenses into water on the wall. This problem can be solved by removing the source of the moisture. Do you have a clothes dryer venting into the basement, a cooking stove, a shower or bathroom in the basement? Any of these can produce more moist air than your basement can handle. Look for a dehumidifier to remove the dampness in the basement.
If the moisture however is on the side of the foil that faced the wall, you have seepage and a more difficult problem. There are three potential reasons for water seepage:
Original construction was poorly done
House foundation settling has caused cracks in the floor or walls
Hydrostatic pressure from the outside forcing water through the walls.
Determine the source of the water and the reason it is being forced into your basement (hydrostatic pressure), either through porous concrete or through cracks and fissures in the floor or walls.