16. Jul 2019

Solar protection façade: Unique lighthouse architecture

The Ecole Polytechnique Fédérale de Lausanne (EPFL) is widely acknowledged as one of the finest universities founded anywhere in the world over the last 50 years. In international competition with other elite universities, it has opted for emblematic statement architecture. For the expansion of the existing Mechanical Engineering Institute (ME) and the merger with the relatively new Center for Neuroprosthetics (CNP), Dominique Perrault elected a three-dimensional zigzag façade consisting of 630 horizontally movable solar protection elements made of metal fabric from GKD – GEBR. KUFFERATH AG.

Spanning 3,000 square meters, the building on the campus of the EPFL, founded in 1969, offers space for state-of-the-art offices, seminar rooms, and laboratories. Its façade is clad with 630 panels – each 1,100 x 3,600 millimeters. They form a vertical and horizontal zigzag pattern that spans the entire four-story building. The panels are alternately affixed at the top and bottom and are made of natural-colored, anodized Escale aluminum fabric, which is fixed in place by means of a stable frame construction using clip bolts. The panels are arranged in groups of three, with two of each group being motorized and moving on rails behind the fixed element in a telescopic manner. Although the complexity of the façade geometry and the size of the individual elements place tough demands upon the bearing structure, Perrault decided to go without rear anchoring of the panels so that his frame construction bears the entire weight of the frame and fabric. As it lies so close to Lake Geneva, increased wind and snow loads as well as total ice coverage had to be taken into account. In order to verify the ambitious static planning, three prototypes of these elements were subjected to real conditions for one year. The panels can be adjusted flexibly for each room to the respective use as office, auditorium, or laboratory, as well as to the time of year, thereby fulfilling key criteria of the ambitious sustainability requirements. The seven millimeter wide and 150 millimeter long spirals intensively reflect the sunlight and lend the large-format façade elements an optical lightness. This makes them the perfect means with which to express Perrault’s intention to design a building without visible walls.