Damp basement walls happen because water seeps through the walls. This water damages structural integrity, and causes mold and mildew, which leads to respiratory and other health issues. This is the reason why its imperative to fix any basement issues before they become serious problems. The first thing you must do when you are fixing these problems, is to find the source of the leak. Upon examining the basement wall, if you find a collection of mold or mildew growing on a part of the wall, there is a leak there where excess water seeps in and feeds the mold. Another way to find out where the leak is coming from is to follow the smell. If there is a musty smell or odor in the air, and its near walls, you have a leak somewhere. Also, examining the walls for instances of discoloration can lead you to the source of the leak. This is because seeping water leaves bright brown stains on your wall when it seeps in. If your walls are leaking, its likely to damage any metal fixtures and wood items by producing excess moisture in the air. Once you have successfully detected that your damp walls are leaking water, you must confirm if it from condensation or seepage. Tape a small piece of aluminum foil to the basement wall and leave it for a few days. When you remove it, if you find moisture on the surface that touched the wall, there is a leak in the wall.