Just add 2 to the width of the actual door size. The diagonal measurements should be the same. Half bathroom dimensions (toilet and corner sink, pocket door) 5ft x 3ft (1.5m x 0. A height of 6ft 8 ins (2.03m) is required in front of all fixture and for a 30 inch (76cm) diameter where the shower head is. The correct size for a wheelchair user to be able to comfortably fit through a doorway is 32 inches wide.
Standard door sizes are available to fit most existing frames but houses move.
Hanging A Door