Bulk bags can be stored outside, as long as UV and environmental impact is taken into consideration. All bags have a “UV” rating in hours, usually around 1600 hours, but that can vary depending on the weather conditions and global proximity to the sun. All of Bulk Bag Depot’s bags have a UV inhibitor added to the fabric when manufactured. While this does offer a limited time of UV protection, it is still recommended that bulk bags be stored in a protected environment.