The ideal humidity level for a basement is between 30 and 50 percent. The prime growing conditions for unwanted mold and spores start at around 60 percent.
Both finished and unfinished basements in warm, humid climates are the most likely to suffer from too much humidity. For one's safety and in order to maintain the maximum value of one's house, it is important to regulate humidity levels. Not only can airborne spores be dangerous to a person's health, but they can result in an unpleasant, musty odor. A dehumidifier will prove more effective than a basement exhaust in combating high humidity levels.