© 2024 EPFL - Illustration by Jeanne Guerard
In a real-world example of how construction materials can be reused, a team of 230 EPFL students is building a community pavilion in Ecublens, near the Lausanne campus, through a low-tech, participative approach. This bold initiative entailed overcoming a number of logistical, technical and architectural challenges.
Children at the Pontet primary school in Ecublens can now admire their artistic creations from the school's top-floor windows: the rebuiLT pavilion, under construction right next door, now has a rooftop dotted with tiles painted in their colorful designs. These children are just some of the community members taking part in this participative approach. rebuiLT was launched at EPFL in 2022 as a MAKE project intended to promote circular economy principles. It's being carried out through an initiative involving EPFL, the municipality of Ecublens and various construction-industry organizations.
There's only a few months to go until the pavilion is complete. The framework and rooftop of the main edifice - large concrete structures taken from a building slated for demolition in Renens - are in place. The walls, made of straw bale and coated in clay, went up this summer, and the windows and a sink were recently installed.
"Our project has evolved over the months, based on the contributions of different people," says Sarah Planchamp, an architecture graduate who's been on the rebuiLT team from the start. The goal is to show how methods based on reusing construction materials can be employed to build a community center. Team members also learn a variety of skills along the way, like how to respond on the fly to the challenges that inevitably arise in this type of venture - especially since the rebuiLT approach is still very new and experimental.
Hunting down the right materials
The first challenge was to find the right materials. A special group was put in charge of this task and visited nearly 100 construction sites and a dozen recycling depots for second-hand construction components. "We also relied quite a bit on word of mouth," says Planchamp. "We physically went to every site to evaluate the components that were available, since there are still no industry standards for this. And we often had to perform the demolition work ourselves, which was a learning experience in itself." The roof's 6,000-odd tiles were sourced from an old farm near Ecublens. The owner wanted to contribute to the initiative, even though it meant dismantling the tiles one by one - a more tedious and time-consuming process than simply throwing the tiles into a waste bin and hauling them to a dump.
In the reuse of construction materials, safety and liability are two major issues that need to be addressed - especially for buildings that will be open to the public. For example, a low-tech, efficient wood-fired heater developed as part of a student project couldn't be used because there was no way to have it certified. The rebuiLT team therefore designed a raw-earth Trombe wall to supply only passive heating.
rebuiLT is an educational initiative, and its team members - consisting of bachelor's and master's students from EPFL's School of Engineering and ENAC - will earn credits for their work on semester projects and workshops this summer. In addition, schoolchildren, volunteers and other community members are taking part in rebuiLT through its participative approach. Planchamp explains that "it's important to set up smooth procedures and to enable participants to share their knowledge as much as possible." According to Xavier Morneau, an exchange student from Quebec who's completing the last year of his bachelor's in architecture at EPFL, "rebuiLT is a great personal experience and excellent field opportunity. We get to combine many different types of construction methods, including some ancient ones. I still remember the day I had to explain to a farmer that we wanted to use his hay to build walls."
Planned demolition
The circular process promoted by rebuiLT requires thinking differently about architecture. "We had to constantly adjust the design based on the materials that were available, and vice versa," says Planchamp. "There was a lot of improvising along the way." The team is already looking ahead to after the pavilion opens in the fall. For instance, they want to map out how they'll manage the structure and its use by the general public, which is currently scheduled to run until 2026. Future student groups will pick up this work and look at the structure's end of life, in particular, which is an integral part of any recycle-and-reuse philosophy.
