Condensation of warm, moist air on cool surfaces often causes dampness in basements. Excessive moisture may indicate that repairs are needed. Some basements are continually wet from water leaking through crevices in the wall. Make sure that outside drainage is adequate and that crawl spaces under houses are kept dry. If a clothes dryer is equipped with a vent, have it exhausted to the outside to prevent condensation of moisture.
Cool air holds less moisture than warm air.
If properly installed, air-conditioning systems remove moisture from the air by taking up warm air, cooling it, and circulating the cool air back into the room. In houses that are not air conditioned, including the basement, mechanical dehumidifiers are useful. If necessary, get rid of dampness by heating the house for a short time. Then open doors and windows to let out moisture-laden air or use an exhaust fan to force the air out. Burn an electric lamp to dry the air in closets and other small areas.