What is condensation and why is it happening in my basement?
Whenever outside air is warmer than inside air, a condensation problem is likely to appear in your basement. Basements are below ground and therefore, most of the time, fairly cool. When moist and hot air (like that found on a summer day) are combined with cool basement conditions, condensation forms on cool surfaces such as ductwork, glass and concrete foundations. Why does this occur? Keep in mind that the relative humidity of air goes up 2.2% for every one degree it is cooled. Consider, for example, an 80-degree day with relative humidity level of 80%. As the warm and moist outside air is drawn into your basement to be cooled to a comfortable 68 degrees, the basement’s relative humidity is raised another 26.4% (12 degrees x 2.2%). Add that to the pre-existing 80% humidity level and you’ve got a number greater than 100%. This is really saturated air – so the air gives up its saturation or excess moisture by “depositing” it on cold surfaces such as basement walls, floors, exposed duct
