Abstract: A method for retrofitting a building using a lift system and a component kit for performing the method are provided. The shaft of the lift system extends over at least two stories 3 and comprises a self-supporting sheet metal box made of at least one steel plate, which is provided for receiving a cabin of the lift system together with its guides and drive devices. The sheet metal box of the shaft has a profiled cross section, which forms a cross-sectional area in the cross-sectional plane within the sheet metal box, which essentially covers the area required by the cabin and its guides and drive devices, and additionally contains the area of a lift platform for bridging a distance between the cabin and the building. The method provides prefabricating the lift system and installing it to the building.

Abstract: An elevator system for installation on the outside of a building which extends over at least two stories and includes a shaft, a car movably mounted in the shaft for movement in a longitudinal direction of the shaft, and a drive for the car. The shaft has a shaft pit at its lower end and a through-opening for each story to be served and is configured as a prefabricated sheet-metal box made of at least one thin-walled steel plate that also extends beyond the shaft pit. The sheet-metal box forming the shaft is self-supporting, in that the steel plates extend in a straight line in the longitudinal direction of the shaft, and are profiled in a plane extending at right angles to the longitudinal direction. The steel plates are formed in one piece over the entire extent of the shaft in the longitudinal direction. A method for producing this elevator system is also provided.

Abstract: A sliding folding door of double-walled construction with the sliding door including a plurality of leaves interconnected by shaped connecting rails. The doors are adapted to be foldable or pivotable about vertically extending pivots disposed inside the connecting rails. Each of the connecting rails includes two cylindrical walls that have a quarter-circle cross section and extend along the connecting rail, with center points of their radius of curvature being arranged in the pivots. Each cylindrical wall has opposed thereto a crosspiece that extends along a long side of the respective door leaves.