SBE25 Conference in Zürich
Sustainable Built Environment (SBE) in Zurich © ETH / SBE25
The 2025 edition of the Sustainable Built Environment (SBE) conference was held from June 25 to 27 in Zurich. On this occasion, Clément Cattin, PhD student at the Laboratory of Architecture Sustainable and Technologies (LAST), presented the progress of his research carried out as part of the RELIEFS URBAINS project. Entitled “Urban sloping sites as an untapped opportunity to diversify housing in Switzerland”, his contribution unveiled a novel prospective cartography methodology.
Sloping sites are especially appealing for habitat due to climatic, safety, or landscape factors. These benefits - which compensate for the construction effort required to build in such areas - have favored the urbanization of the hillsides throughout history. With the rise of private cars, the accessibility of urban hills has increased, mostly leading to a loose settlement of privileged, detached homes.
At a time of climate emergency, the continuation of urban sprawl is strongly questioned. Urban regeneration projects aimed at increasing housing density, with a mix of functions close to public transport, are among the responses provided today in Switzerland. However, the population is often not very favorable to density and these projects are increasingly being rejected. Therefore, the RELIEFS URBAINS research considers hillsides as a contextual specificity of Swiss cities capable of responding to the urgent housing crisis while offering housing diversification with high habitability qualities.
Because slope is a condition that extends beyond the Alps, the study area of this research encompasses the perimeters formed by Swiss urban territories and focuses on sloping sites with good accessibility. This presentation demonstrated the quantitative and qualitative potential of these sites using prospective cartography, showing that hillsides of agglomerations could be a reservoir of polycentric, decarbonized, and adapted densification projects, contributing differently to the urgent need for quality future habitats.
Under the topic “Shaping Tomorrow: Systems Thinking in the Built Environment”, the SBE 25 conference showcased the benefits of interdisciplinary, cross-sectoral, multifunctional, multiscale, multidomain, and multistakeholder approaches. The contributions demonstrated the application of systems thinking to developing and implementing solutions for a more resilient, fair, dignified and sustainable built environment.