Innovating within Lausanne's medieval stone walls

La spirale en construction dans le chœur de la Cathédrale de Lausanne. © EPFL - Jamani Caillet

La spirale en construction dans le chœur de la Cathédrale de Lausanne. © EPFL - Jamani Caillet

Starting this coming Saturday, an opera will be staged in Lausanne Cathedral for the very first time. Giuseppe Verdi’s Nabucco will be performed by the Amabilis orchestra, the Horizons choir and a number of world-renowned soloists, on a highly imaginative set. The capacity crowd of 760 people will sit on special wooden bleachers – assembled without nails, screws or glue – that were developed by EPFL’s IBOIS lab. 


The story of Nabucco is one of poignant oppositions – magnificence and decadence, strength and submission, history and technology. These will be on full display in Lausanne Cathedral for the opera’s week-long run starting on 17 November. But some aspects of Verdi’s famous work, which he composed in 1842, have been updated: the story will feature a nod to the European migrations of the mid-20th century, for example, while the staging takes advantage of current-day building technologies.

Spectators will be captivated by the music of the local Amabilis orchestra, the Horizons voice ensemble and internationally known soloists. They will also experience a world first: the opera set and seating are made entirely of wood. They were developed by EPFL’s IBOIS laboratory under the direction of Yves Weinand. (Click here for more information.)

Three sets of bleachers comprising a total of 760 seats surround a towering spiral that symbolizes Nebuchadnezzar’s thirst for power. The combined structure – which fits neatly into the gothic church’s nave and transept – is in itself an architectural feat, as it was built without the use of nails, screws or glue. “The underlying technology came out of our EPFL lab,” says Weinand. “We took a well-known technique – wood mortise and tenon joinery – and then developed and patented a system of snap-fit joints that draws on the wood’s natural elasticity to facilitate the assembling process. This approach results in very solid interlocking joints that can be easily dismantled as well.”

The wooden panels for the seating were prefabricated by local firms. Laid side by side, they would cover half a soccer field. The seating structure was put up in just over a week by a handful of musicians and singers involved in the project. Once the performances are over, the bleachers will be taken down and sold.