Tips and Tricks: Storing Mattresses
… Wrap your mattresses in the special bags available at most supermarkets and DIY stores. These not only prevent them from losing shape but protect them from absorbing moisture as well. Use a dehumidifier to draw out excess moisture from the unit you use if needed, but the self-storage facility should already be temperature controlled to prevent this. Check on the mattress occasionally to see if it needs adjustments to storage conditions. If you store it for longer than a year, change the plastic covering once annually.