Frankfurt am Main, Germany

Ferdinand Heide’s winning project for a new sky tower in Frankfurt called Millennium Areal and designed for real estate company CA Immo will be clearly visible in the cityscape with a design that solves the needs of the city—the integration into the skyline and the surrounding area—as well as the question of the best floor plans and according to the most efficient construction. 

The winning scheme imagines the construction of a 280-meter office and hotel tower for Tower A and a 157-meter residential tower for Tower B, along with a block perimeter building in a wood hybrid construction.

The towers will be twisted to create spacious terraces and recesses in the building’s structure, as well as increase the distances between them, which offer additional lighting in the flats of Tower B and increases the energy yield for photovoltaic systems integrated into its façade.

In addition to the public facilities placed at the ground floor, a viewing platform and events space are placed at the very top of Tower A, offering visitors a panoramic view of the city.

The higher of the two towers—with the project title Tower A—will be visible from many points in the city with a shape, a surface, and a significant point that can be read from different viewpoints and in a different light as a twisted sculpture and with a constantly varying appearance.

On the construction site (8700sqm) and its surroundings, the aim is to find a figure who reacts to the special features of the location, despite or perhaps because of the supposed density.

In other words, the central design idea is as obvious as it is simple:

The volumes of Tower A and Tower B are shaped in such a way that the largest possible space is created between the two and as a joint to Tower 185 and that all offices and apartments enjoy as much of a clear view as possible. 

This is achieved by untwisting both towers and facades.

Turning it up causes a maximum distance and the greatest possible incidence of sunlight to be ensured in the lower area—where the supposed narrowness is greatest. 

The green spaces in between are open and sunny in two directions. 

Terraces resulting from the rotation develop upwards and can be used by the public.

The entrance hall on the ground floor can be found as a counterpart and to the structure of the tower as public and readable sky lobbies at a great height. 

Once again over the full width of 60m and with double the room height (9 m) are the hall, the restaurant and the hotel garden on the 29th floor and the distribution lobby, and the meeting rooms on the upper office levels on the 42nd floor.

Without exception, all apartments are oriented to the south, west, and east, each has incised loggias and is staggered in such a way that their story-high facade elements have the best possible orientation. 

The alternation of loggias and winter gardens creates a varied facade and different qualities.

The standard floors of the towers, which are slightly different due to the rotation on each floor, show the essential floor plan organization of the houses. 

In the office tower, there is a mighty core with 18 elevators and all ancillary rooms and ring-shaped surrounded by office areas with a depth of 8 to 15, which enable individual, combined, and open-plan offices.

The conclusion is the Skyhall—a top for Frankfurt. At a height of approx. 266m, the public is offered a spectacular space, which winds upwards as a stairway to heaven and which faces the city center and the banks of the Main. 

Far more than the actual required visitor platform and with a unique selling point in Europe, we envision a glazed 18m high room on whose seating steps, which once again address the skewed and twisted levels of the building, the visitors can enjoy the special place.

The construction of the project is consistently developed from its special shape. 

The load-bearing core is surrounded in a uniform grid by basic columns, which, as load-bearing members straight across all 68 stories, absorb 80% of the ceiling loads. 

Only the ceiling edge areas resulting from the twist are supported by inclined facade supports following the rotation. 

A total of 5 times over the full height in the area of the lobbies and the technical centers, the extremely high wind forces of such a high but slim building are carried away with so-called outriggers, which lead diagonally to the core.

Eight renowned international architectural firms were invited to participate in the architecture competition, which include 3XN Architects, David Chipperfield Architects, Cobe, Herzog & de Meuron, Ingenhoven Architects, OMA, and Schneider + Schumacher Architekten. 

Project: Millennium Areal
Architects: Ferdinand Heide Architekt BDA
Project Leaders: Ferdinand Heide and Lorenz Heide
Design Team: Philipp Sontach, Kim Hübner, Vjekoslav Buha, Sandrina Schliemann, Daniel Glebe, Claudia Zimmermann, and Frank Heinen
Structural Engineers: SWECO GmbH
Facade Planning: Priedemann Fassadenberatung GmbH
Client: CA Immobilien Anlagen