To extend the life of your clear Marine windows for storage always roll do not fold, store dry and use only approved cleaners. Windex is not an approved cleaner! Klear To Sea is an approved cleaner. Keep canvas/materials dry and free of dirt and debris. Mold and mildew will attach itself to dirt and then damage your fibers. Only cover it once to protect it, if you cover it with a second layer you may create mold or wear between the layers and do more damage to the expensive cover you were trying to protect.