Obviously keeping water out of your storage unit is always important, and storage facilities will strive to prevent any possible water damage. If you are particularily concerned about water damage, dehumidified storage units are often available for rent at storage facilities. In a dehumidified storage unit, extra precautions are taken to keep all moisture out of the storage area. Many storage facilities also offer climate-controlled units which monitor the temperature inside the individual storage units. If you will be storing electronic equipment or computers, it is a good idea to have a climate-controlled unit. Contact a local storage facility for more information on climate-controlled units.