Industry Standard is that you add at least 2″ to the overall dimension of the door size, to determine your RO. For example, if you order (1) 30″W x 80″H size door, your RO needs to be at least 32″W x 82″H for a single door application. If you are ordering for a double door application, and want to use (2) 30″W x 80″H size doors inside your one opening, your RO needs to be at least 62″W x 82″H.