Reversible, expressiv, vibrant
After a contest in 1969, one of Hypovereinsbank’s predecessor institutes, the Bayerische Hypotheken- und Wechselbank AG (Hypo-Bank) commissioned us to plan a new administrative centre, and to supervise its artistic creation.
By studying the internationally dominant scene of the American cityscape, with a variety of skyscrapers emerging from its historical development, we mainly learned what was absolutely out of the question for Munich! So for instance our desire for ‘form’ was by no means to be fulfilled by added decoration, but through the expressive flow of the building mass in and of itself.
Crucial starting points for drawing up the plans were the functional specifications for the design of the 2,500 reversible workspaces, which could easily be transformed from open-plan offices into single rooms and vice versa.
Requirements in planning for reversible use:
- Workspaces in a quality that is as equal as possible, with views of the outside.
- A minimum net floor space per floor of 1,300 m² to 1,500 m², i.e. for about 100 employees.
- Circulation should be concentrated on the edges, not the inner zone.
- No constrictions that impede the pooling of work groups when using open-plan offices, but a clear structure.
For the purpos of reversibility, each window axis in the HVB ensemble is ‘viable’ on its own, i.e. equipped with air conditioning, lighting, all media, fire protection, and sprinkler systems, as well as being independent from the suspended ceiling.
A standard floor in the HVB-Tower, which is set on top of a low rise building and accounts for about one-fifth of the building mass, consists of three equilateral triangles, which in the upper floors first taper to two and ultimately to one triangle. On the one hand, the floor space is structured as an open-plan office and designed in an easily manageable way. On the other hand, it can quickly be converted into individual rooms with almost no wastage due to darker inner zones.
The departments with very large space requirements are housed on a separate floor in the northern part of the low-rise building. Thanks to insets and the inclusion of internal courtyards, these areas appear uncluttered and well-structured, and each workstation has a view of the outside. The southern part of the low-rise building accommodates special uses (conference area and staff restaurant). In the basement a road used for deliveries and waste disposal ensures access to the building.
The conventionally constructed low-rise building was erected on a support grid of approximately 10 x 12 metres. In the high-rise building, the central support frame – with suspended floors towards the bottom and supporting floors towards the top – stretches between the four towers. The encompassing frames clearly demonstrate the flow of forces. Once the low-rise building was completed, the supporting floor was prepared on the ground floor as a platform, hydraulically raised, and cast in concrete at the final height.
At 1.40 metres, the spacing between the axes of the façade is derived from the smallest desired biaxial single room, with a height division of 120 centimetres.
The metallic-looking surface of the reflective glass used (with underlying anti-glare protection) won us over with its varying colours and reflections depending on weather conditions. As a kind of ‘lizard skin’ that often adapts to the aluminium tone of the façade, it is uniformly distributed over the building and highlights its plasticity.
As the building, especially the high-rise section, appears to be freely raised, the façade had to be carefully planned also in the transitions to the vertical. After six months of working out the major technical and design details in 3,000 drawings, no more changes were possible during the construction, as the general contractor based his calculations on this information.
In his day, the Munich-based architect Friedrich von Thiersch expressed his regret that not one of his buildings achieved the freshness of his designs. This problem of execution has certainly become even more serious since. Today we are happy and quick to show our designs and diagrams, increasingly following the tendency to develop them into small works of art, but have to admit that from concept to design is one step, but from design to a finished building is 1,000 steps.
Beatrix und Oliver Betz
Betz Architects, Munich, was founded in 1956 by Walther and Bea Betz.
In 1993 Oliver Betz joined his parents’ firm. In 1999, the Hypo-Haus-Ost (‘Hypo Building East’) on Denninger Strasse was inaugurated as an extension to the existing complex, featuring a movable glass sunscreen and light art by Dan Flavin. In 2009, Walther and Bea Betz received the City of Munich’s Architectural Award.