TK Test Tower in Rottweil or How a Membrane Envelope Saves Weight

Standing at approximately 246 m (807.08 ft.), the ThyssenKrupp elevator company’s Test Tower in the town of Rottweil is one of the tallest buildings in Germany. The tower was designed by Werner Sobek together with Helmut Jahn. It is used for testing and certifying innovative high-speed elevators. Both from an engineering and an architecture perspective, the ThyssenKrupp Test Tower was an extremely challenging structure that required close coordination between the planners, the contractors, and the client. The planning of the membrane envelope was particularly demanding, presenting the planners and the contractors with many new challenges. Since the second skin made of fabric played a special role regarding the targeted weight savings and the special design of the tower, it was the focus of the design process. The Test Tower is more than just a functional structure for researching and developing modern elevator technologies. Its 232 m (761.15 ft.) high public observation deck (the highest viewing platform in Germany) allows visitors to enjoy breathtaking views (Figure 1). Moreover, the structure is also the tallest textile-clad building in the world. This innovative textile skin is integral to the building’s architectural and structural concept (Figure 2). The client’s and the planners’ wish was to erect a materialefficient building in the shortest possible time that harmoniously fit into the surrounding landscape and the silhouette of Werner Sobek Werner Sobek AG