Thought Bubble

With the buzz surrounding Foster and Partners’ nearly completed Hearst Headquarters in New York, it would be easy to overlook another new and important project. The Philology Library, at the Free University in Berlin—one of the firm’s greenest schemes to date—represents years of research into the use of active and passive technologies for more energy-efficient buildings.

A striking glass-and-steel structure reminiscent of Buckminster Fuller’s geodesic domes, the library is located in the center of campus. It is part of Foster’s master plan for the school, which also incorporates restoration of a complex of Modernist buildings completed in 1971 by Paris-based firm Candilis-Josic-Woods, Scheidhelm (with Jean Prouvé designing the facades using Le Corbusier’s modular proportional system). Over the years the old buildings, originally clad in narrow strips of Cor-Ten steel, had become known as “die Rostlaube” (“rust bucket”) because of their decaying facades.

Senior partner Stefan Behling—Foster’s resident expert in ecology, sustainability, and energy conservation —says the team debated a long time over how to contrast new and old, and decided to look at the library from the inside out. “Originally we had book racks going four stories up into the air, where you’d be sitting on this mountain of books,” Behling says. “We realized the perfect solution was some kind of monk cell—something more abstract, timeless, and contemplative. That’s when we came up with the idea of a wide parachute or balloon that would wrap over the whole thing.” The building combines a concrete structural mass with a curved translucent double-layered skin that dramatically diffuses daylight and naturally ventilates the space. The membrane is Behling’s favorite element in the project. He compares it to sitting with a white umbrella under a tree and watching leaves cast shadows to create a beautiful play of light and pattern: “In the library, if you are reading and look up from your book, you actually notice how clouds move over the building because the light changes on that surface. It’s like a natural light projection screen.”

Behling says the library’s form is part of a long Foster and Partners’ lineage, going from the Swiss Re Building to the Reichstag, and even further back to the 1970s, when Norman Foster worked with Fuller on the Climatroffice—a research project that looked at transparent tensegrity structures with internal microclimates.

Behling’s perfect building is, of course, the planet Earth. He describes its atmosphere as “a funny layer of dynamic gases and clouds constantly moving around this globe, somehow making it possible for us to live. That layer to me would be the perfect skin. The Free University is trying to go in that direction, and it’s doing it more than any other building I know. Next time we’ll do it with just air and gases moving, and no space frame.”