In cases of little room for door leafs, lift doors or lift gates can be used, which move either on the outer or inner surface of the wall or in slots within these. Elevator lift gates are only authorized for freight elevators. Lifting doors/gates are used for very large passage widths where leaf, folding and sliding doors cannot be used.
Lift Gates, as the name suggests, are opened by a lifting movement. The area covered by the open door panel may not be used for windows or other purposes. There are also divided lifting doors, in which the upper half of the door opens upwards and the lower half of the door opens downwards. One half of the door forms the counterweight of the other. This arrangement has proven success particularly in elevators, where double doors stop the through traffic and where there is not enough space for sliding or undivided lifting doors.
The space in the upper halves of the respective floors is thereby alternately used by the door parts of the above or the underlying stops, therefore they cannot be opened simultaneously.