On Friday, February 13 2004, the winning designs in the international urban planning and architectural design competition for the new European Central Bank Headquarters (ECB) were presented to the public.

An international jury chaired by the ECB’s Vice-President Lucas Papademos chose the winners from around 300 applicants and awarded the 1st prize to COOP HIMMELB(L)AU (Vienna). The 2nd prize goes to Schweger + Partner (Berlin) and the winner of the 3rd prize is 54f architekten + ingenieure/ T.R. Hamzah & Yeang Sdn Bhd (Darmstadt/ Selangor).

The winning design comprises three components: the historic Großmarkthalle – the former wholesale market hall, a groundscraper running parallel to the Großmarkthalle and two approx. 150m (~500ft) tall sculptural towers. The Großmarkthalle will serve as ECB’s main entrance and public area and a conference center is planned for the groundscraper. The two tower complex will be the visual highlight of the project. The entire development with office space and special areas covering a main usable area of approximately 100,000 m² will accomodate 2500 workplaces.

COOP HIMMELB(L)AU’s concept:

‘The site of the ECB’s new headquarters in Frankfurt’s ‘Ostend’ has the potential for creating a visible icon. Starting from a research base of urban sightlines and cones of vision, we proposed a polygonal-shaped double slab tower in the east-west orientation. The narrow side of the tower profile is a solitary figure seen from all of downtown Frankfurt’s major viewpoints (the old opera house, the Museumsufer and the banking district). Its form and presence becomes an unmistakable fixture on the Frankfurt skyline.

Revising our original design, we proposed increasing the height of the two towers from approximately 150m to 180m. We are convinced that this will strengthen the solitary figure by enhancing its proportions from all of Frankfurt’s major viewpoints and from along the river Main. The increased height again reinforces the two towers’ dual concept of space and form without changing the symbolic connotations of their distinctive shape: communication, transparency, efficiency and stability.

The site

In the local urban context, the double horizontal structures connected with the vertical diagonal cut of the atrium of the towers, creating a vertical city and connecting the ECB with the larger urban network of Frankfurt’s skyline. In this way we have left the existing Grossmarkthalle untouched and provided a prominent view across the strong horizontal space of the river and a functional connection to the existing building for the new conference facilities.

So that the Grossmarkthalle can be seen better from the south-west, we moved the entire building eastwards by 15m and reduced the height of the ‘groundscraper’ by up to 4m. This way the south-west corner of the Grossmarkthalle can be seen from across the river Main. This reinforces both the spatial ensemble of the two horizontal structures and the verticality of the two towers.

The ECB complex

Combining the horizontal structure and verticality of the two towers gave expression to the ECB’s functional program. The Grossmarkthalle houses the entrance lobby and all public and semi-public functions, such as exhibition space, a visitors’ center, the library and an auditorium for press conferences. The groundscraper – the horizontal connection to the office towers – contains the two-level conference center with its own lobby and restaurant. The towers provide most of the office space.

The tower’s typology

A sculptural transformation of torsion and bending applied to an economical double slab high-rise typology offers the following advantages:

*It creates differentiated office spaces by slightly varying the floor-plan development and views.
*The dynamic shaping of the atrium space between the tower slabs acts as a communication forum and hanging garden.

A vertical city

We also proposed a ‘vertical city’ inside the atrium. Through numerous connecting levels we inscribe between the towers the spaces and circulation similar to a city. The main levels divide the atrium horizontally into three sections – like city districts – which are approximately 60m high.

Two large platforms connect the two office towers in the lower third of the atrium and form a busy marketplace with recreational hanging gardens, a cafeteria and lounges for informal meetings between all occupants. The space created by these ‘interchange platforms’ and meeting lounges gives a western view of the Frankfurt skyline.

Many ’short circuit’ elevators and ramps connect the various office floors across the atrium providing the opportunity for larger floor plates by connecting space functionally across the atrium. These stairs and ramps act as streets and passages within the vertical city; offering short, direct connections and populating the space with inhabitants.

In addition to these horizontal elements, the atrium contains vertically connected hanging gardens and daylight reflectors, bringing light and greenery into the vertical city. By reinforcing the dynamic internal communication culture of the ECB the solution will create an unprecedented symbol in the urban context, representing the public dimension of the ECB within Europe and the world.’