In 1974, the 108 meter high existing building was built according to the plans of architect Richard Heil as one of the first high-rise buildings in Frankfurt. In the meantime, the high-rise façade, designed in the International Style, has been listed as a historic monument due to its significance for urban development. Under the leadership of the architectural firm Holger Meyer, the building had to be reduced to its low and shell structure as part of the comprehensive modernization, and the entire technical systems had to be renewed. With regard to the building’s envelope, the decision was made to use a double facade. The inner façade layer takes over the technical, functional and energetic functions of an air-conditioning envelope, while the outer skin replicates the flatness and framelessness of the original façade. For this implementation, the Global Tower was one of the first high-rise buildings in the banking district to be awarded the WiredScore as well as the DGNB Platinum certification for particularly sustainable building standards. Another special feature of the building is the flexibility of its interior design. Thanks to state-of-the-art wall installation technology, open-plan offices, for example, can be converted into separate individual areas within just a few days.