Description

The Autobahnüberbauung Schlangenbader Strasse, a housing project spanning a busy freeway, is the first implementation of an architectural vision that had been developing in response to the explosive growth of cities and motorized traffic since the early 20th century, with urban planners and architects such as Edgar Chambless, Hugh Ferris, Hans Schierloh, Le Corbusier, Paul Rudolph, and Kenzo Tange exploring new approaches to urban planning in which traffic axes and superstructures were fused into multifunctional structures. The ideal structural form for this was the likewise newly developed typology of the stepped terrace house, the dark “belly” of which could accommodate traffic routes.

Rapid automobile transport seemed desirable in those decades of technological optimism. In the 1950s, zoning plans for West-Berlin included a motorway ring around the city center. The particular situation in West-Berlin, especially the limited land, provided the impetus for this first superstructure development above an autobahn section.

The technically complex and costly experiment was initially carried out by a private client. Heinz Mosch AG developed the pioneering project in collaboration with the architects Georg Heinrichs and Gerhard Krebs as well as with experts in traffic, noise protection, aero-dynamics, etc., and supported by political decision-makers. Georg Heinrichs was the project manager, with a stance decidedly reminiscent of 1920s modernism.

When the oil crisis hit in 1973, the edge building along Schlangenbader Strasse was already under construction, and the property developer ran into financial difficulties. The public sector stepped in and the German Society for the Promotion of Housing Construction (degewo) in Berlin, founded in 1924, continued the building as an exemplary project of the federal government within the framework of subsidized social housing. This led to a stronger social orientation of the company in terms of rents, infrastructure, and the remarkable green and open space design.

The notion of a motorway in the “belly” of a residential building was an undertaking without precedent, with the possibility of technical solutions for sound insulation and exhaust fumes doubted by many. The prerequisite for success was the construction of two tunnels completely separate from the residential buildings themselves. The superstructure runs a length of almost 600 meters and reaches a height of up to 46 meters. The motorway tunnel bridges Wiesbadener Strasse, which crosses in the middle. Seven access towers, set 60 meters apart, give the large structure a rhythm. They also articulate the inflection points in the complex, which follows the curve of the motorway. The lower seven floors of the superstructure are set back and fronted by terraces. Above them are up to six stories with loggias and a terraced rooftop level. Parking spaces for about 760 cars are located on two levels below the tunnels. The supporting structure is a reinforced concrete, cross-wall construction.

A lower, five-story block runs parallel to the superstructure on Schlangenbader Strasse. At the northern and southern ends of the complex, where the tunnel sheath ends, more five-story buildings, including a multi-story car park, provide additional screening and noise protection. Generous greenspaces are situated along both sides of the superstructure.

On the eastern side, the edge buildings on Schlangenbader Strasse turn these into sheltered courtyard-like areas. Although the large structures of the development introduce a completely new typology, towering above the surrounding buildings with over 40 meters height, it is at the same time integrated into the surrounding city. Above all, it is thanks to the superstructure that the neighborhood has been preserved as a coherent urban space despite the motorway. Neither in the complex nor in the apartments does one hear any noise from the up to 80,000 cars that drive through daily.

The ground floor zone on Schlangenbader Strasse is generous and open, filled with restaurants and shops, thus enriching the neighborhood with a new semi-public layer. The residential complex shares its rich green space with the neighborhood.

A guiding principle of the Schlangenbader Strasse development was the creation of a mixed city, particularly in social terms. To encourage diversity among the almost 4,000 residents, a wide range of housing typologies was developed. Thirty percent of the apartments were intended for single people, 30 % for couples, and 40 % for families. 80 apartments were specially designed for elderly occupants.
At a distance of 6.4 meters, the cross walls define apartments width. The apartments in the superstructure are accessed above the tunnel via central corridors. Storage rooms assigned to the apartments on the fifth floor are located at the center of the building. Half of the apartments have terraces with an average size of 15 m2. The apartments on the upper, non-terraced floors are equipped with loggias. The two upper floors hold maisonettes with terraces facing west and east. Thirty percent of all apartments are maisonettes.

Corner glazing to the terraces, horizontal windows, and in some cases skylights provide good lighting. There are open plan kitchens or bar kitchens. Folding doors ensure flexibility. Baths and toilets are separate and many bedrooms have en-suite bathrooms. The hallways of the larger apartments go full circle and the bedrooms have walk-in wardrobes. Foyers and stairwells are carefully designed in terms of color, feel, and form and have direct incoming light.

A variety of communal spaces promote interaction. The entire fourth story, above the tunnel, is designed as a shared floor. Here, one can traverse the entire length of the super-structure on an internal street. “Connected to this indoor street are four common rooms near the center, each 80 m2 in size with a terrace, and equipped with a kitchenette and toilet facilities. These rooms can be used for parent-child groups, homework groups, lectures, or for festivities. On the other side of the corridor there are 12 playrooms measuring 6 by 12 m, where table tennis tables and similar equipment is set up. 80 rentable hobby rooms with an average size of 8 m2 also line this indoor street, intended as an extension of the apartment to be used for various activities.”[1] Shared terraces are located at the southern and northern ends of the indoor street. The provision of guest apartments was also innovative and the same is true of the hobby rooms.

Great significance was given to the planning of the green and open spaces extending on both sides of the development (designed by landscape planners Paul-Heinz Gischow and Walter Rossow, 1979–1981). Years before the completion of the building, the developer, with foresight, purchased the trees. Planting and the landscaping of the terrain divide the extensive open space into various play and relaxation areas. Four art installations (by Haus-Rucker-Co and Georg Seibert) demarcate the main intersections of the transverse, longitudinal, and diagonal paths and personalize the large facility. A vertical green space has been created by the planting of the private terraces, enabled by concrete planters suspended in front of the facade. The planters also act as an efficient privacy screen.

The Schlangenbader Strasse development was intensely criticized by the media, who rejected the project after completion. Protest against the development was often combined with protest against the construction of the motorway itself. From the very beginning, however, the residents were highly satisfied and vacancies and fluctuation were low. A tenant satisfaction analysis conducted by degewo in 2018 once again showed above-average satisfaction.

The architectural and historical uniqueness and high quality of the residential complex, which has proven itself in the almost 40 years of its existence, was finally acknowledged in December 2017 in a decision by the Berlin Monument Authority to list the building. The preservation of the Schlangenbader Strasse development has not only been interpreted as a historical appreciation, but also as a stimulus for future residential construction. Architectural historian Nikolaus Bernau wrote: “Here you can see the individuality that large-scale industrial housing is capable of.”[2]

 

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Originally published in: Gerhard Steixner, Maria Welzig (eds.), Luxury for All. Milestones in European Stepped Terrace Housing, Birkhäuser, 2020. Translated by Anna Roos, abridged and edited for Building Types Online.