Aussersihl Community Center by EM2N Architects

October 27, 2008

The Aussersihl Community Center in Zürich, Switzerland was designed by EM2N.

Visit the website of EM2N Architects – here.

Text from the architects:

How to build something hotly contested in an almost sacred spot? From the outset, it was clear that this project would be political, since the building task of Community Center is a public one, and the location in a protected historic garden memorial is very sensitive. Therefore, we tried to make a political, strategic project.

In the competition we formulated a thesis: Not the building alone is the Community Center, but the entire park. This meant, that clearly, the building is a guest in the park, an addition that adds desired extra program. But the park is more important. Clearly, all trees would have to be kept. And considering the small size of the Bäckeranlage as the only green park in this part of the city, the additionally consumed surface would have to be minimized.

Vertical Building
These considerations led to a stacking of programs and the development of a vertical building type, something quite unusual for Community Centers that tend to spread out horizontally. In the competition project, we worked with the typical Swiss neurosis: we want something new, but we don’t want to see it. Things should improve, but we don’t want anything about the outer appearance to change. Rem Koolhaas once remarked, the typical Swiss project tends to bury itself into the ground. Our vertical building type did the opposite. So to satisfy Swiss paranoia, in the competition project we decided to cover the building with mirrors, effectively camouflaging its mass in the park behind a reflecting glass facade. The structure of the building responded to this by developing into a series of vertically stacked structural concrete slabs and floor plates. This allowed us to generate huge openings without columns and really open up the building to the park.

Budget Reduction
The project was worked out and proposed to the municipal council. The political nature of the project made emotions run high. After sharp debates and several attempts to kill the project altogether, a compromise was worked out. We were asked to find out, how much we could build for CHF 3.0 mio.

Holding on to the Original Thesis
It was clear to us, that there was only one possible way to build in the park: preserving all the trees, minimal footprint, stacking the program. We accepted the commission under the condition, that the original thesis would still be kept.

Radical Simplification
However, the radical budget cuts forced us to adopt a new strategy when it came to the actual architecture of the building. The first project had ended up a high-tech glass tower with double-layered facade and high-end technology like activated building mass cooling systems. We felt that merely shrinking the building would not be enough. The community center would not be able to offer enough space to really be of importance for the people. Therefore, we decided to build as much space as possible for the allotted budget. This led to a radical simplification of the building. Everything turned low-tech, now. The facade became wood. The structure, became conventional with lime brick walls, carrying brick facades and concrete floors. Wherever possible, layered constructions were avoided. For example, on the 2nd floor, the floor is one layer of solid concrete, poured in one go, with no further treatment. Also, sophisticated building technology was deleted as much as possible. Like this we managed to reduce costs by almost 45% while only building 20% less floorspace.

Color as Building Material
Instead of using elaborate materials on the inside like fairfaced high-quality concrete, mirroring walls, glass partitions and shining ceramics as wall cover, we used color as a building material. We painted the different floors in different greens and yellows. The bright orange of the staircase contrasts with this color family, just like the blue of the restrooms.

Blending into the Park
From the outside, the building still had to integrate with the park. We tried to achieve this with the free form which swings around the root perimeters of the adjoining trees. This shape was finished in vertical wood siding treated with dark green color found among the evergreen trees in the park. As a result, the building blends in year round. In summer it is hard to be found among the leaves, in winter it stands dark among the barren trees. The large panorama windows were glazed with plexiglas, an economic way of constructing curved glazing. To further blend the building with its surroundings, the skin was pierced by holes and tattooed with circles, evoking the image of tree bark and visually connecting the building with its leafy natural neighbors.
Address: Aussersihl Community Center, Hohlstrasse 67, Zürich, Switzerland

Commission: 1999 Open Competition, 1st prize

Timeline: 2000 –01 First project, CHF 5.4 mio, failed political approval
2002 New budget limit set by parliament
2002-04 Second Project, CHF 3.0 mio, completed

Client: Department of Social Welfare, City of Zürich

Budget: CHF 3.0 mio inkl. sales tax

architects: EM2N Architekten ETH/SIA Mathias Müller Daniel Niggli, Zürich

Projekt architect: Barbara Frei

Construction supervision: Jaeger Baumanagement, Zürich

Structural Engineer: Tragwerk Bauingenieure GmbH, Affoltern a. Albis

Technical installation Planning: Amstein+Walthert AG, Zürich

Wood construction planning: Pirmin Jung Ingenieure für Holzbau GmbH, Rain

Fotos: Hannes Henz Architekturfotograf, Zürich