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The recommended humidity level for bamboo flooring is 35%-60%. For those living in extreme climates (very high or low humidity) certain precautions should be taken before installing your bamboo floor. To help prevent warping or shifting of your bamboo flooring due to humidity levels outside the normal range, use a humidifier (for low humidity or dry climates) or a dehumidifier (for high humidity. A humidifier releases moisture into the air and can prevent cracking, while a dehumidifier helps absorb excessive moisture in the air.