Growth of dust mites Mould problems Increased Allergic reactions
In excessive humidity, water condenses onto (cold) surfaces, causing water damage and mould problems. High humidity also favours the growth of dust mites.
High humidity may result from poor construction/rehabilitation, site design that does not properly manage water, and/or inadequate air exchange. A reasonable target for relative humidity is 40-60 percent. A low cost hygrometer, can be used to measure relative humidity. In cool climates, inadequate ventilation in the winter can contribute to excessive moisture and humidity because normal activities create moisture (cooking, bathing, breathing). Dehumidifier and mechanical ventilation can help remove the moisture.