Sometimes in hot, humid weather, basement walls become damp from condensation of water coming out of the air and not through the wall. If you are experiencing something similar to what is described above, do this
✓ Set a portable refrigeration-type dehumidifier over a floor drain
✓ Do not open the basement windows to let hot, humid air infiltrate, allowing this may cause an addition of moisture into the basement to condense on the cool walls.
✓ Tape a piece of clear plastic wrap or aluminium foil on the wall and check in a few hours to see which side is fogged up. If the taped side exposed to the air gets wet, this is a clear indication of condensation not water seeping through the wall.