The Schauspielhaus in Düsseldorf captivates with its sculptural large-scale form. It is an important representative of the architectural design language of the post-war period. In order to preserve the charm of the somewhat aging building, the facade and roof were extensively renovated. The latter was brought up to the state of the art as a warm roof and (in some areas also) as a green roof. The thermal standard of the façade also had to be raised significantly – but all the doors and skylights, as well as the steel and glass façade on the first floor, were renewed true to the original and in accordance with the requirements of the preservation order. Werner Sobek was responsible for the structural and facade engineering of the project.