Humidity regulation, whether by a humidifier or dehumidifier, helps with comfort levels in your home. According to Richmond’s Air Heating & Air Conditioning , a good humidity level for the home is between 35% and 45%. You can measure this with a hygrometer or you can try a few tricks like the one found here for low humidity measurements, or here for high humidity measurements. High and low humidity can each create different issues in your home and body. Low humidity can damage your furniture, floors, and doors, causing them to crack. It can even cause caulk or glue to shrink, creating gaps that allow air to leak out. Worse, high humidity affects sleep , and exacerbates breathing problems like asthma by creating a breeding ground for mold and other allergens . Low humidity is also problematic, causing dry skin, nasal irritation, and even spreading the flu .