The architects involved were especially concerned about preserving the existing listed building, which was in danger of demolition, as an important corner stone of the city of Dortmund. Hence the challenge of this project was to combine old and new building parts to be both a functional and aesthetically appealing building complex. Accordingly, the demands on the building materials to be used were quite high. In close cooperation with the architect, the executing metalworking business, the company Tesche in Lüdenscheid, decided in favour of the window system heroal W 72, the curtain wall system heroal C 50 and the door system heroal D 72. These heroal system solutions also convinced the managing architect Mr Frank Köller: “The heroal products used fulfil our high demands on quality and design. Especially the slim profiles and the look of the opening sashes, which seem to be almost frameless, are very convincing.“ In addition, the heroal systems used exceed the special ratings required for the construction elements, such as thermal insulation and sound protection. Also, the face widths of the profiles appeal, because of their narrow design. The system producer, the metalworking company and the architects worked closely together in order to create special solutions meeting the individual demands on the project. In addition, heroal’s project service provided support and consultancy for all trades involved during all construction phases.