Crawl spaces where relative humidity (RH) is high are common sites of hidden mold growth, particularly if the crawl space has a bare earth floor. The soil will wick moisture, through capillary action, from moist to dry areas. The relative warmth of the crawl space will dry the soil by evaporation, adding this moisture to the air in the crawl space where it can cause mold to grow. Also, in areas where the water table is high and weather conditions are suitable, ground water may enter a crawl space. The moisture that accumulates in a crawl space may also enter another part of the building and contribute to mold growth there. Moisture can pass from a crawl space into a building through cracks in walls, floors, and ceilings