Sustainability, a "raw material" for architects

You say that sustainability increases the complexity of your work without slowing down inspiration. How do you optimize this constraint?

The first reaction following the oil crisis at the end of the thirty-year post-war boom was to focus on the thermal insulation of buildings. Energy issues were considered as a problem to be solved rather than an element that could stimulate the emergence of new architectural paradigms. Forty years later, the stakes became simultaneously more complex and diverse. This opens up new issues to be addressed, but also new opportunities to be explored. By considering sustainability early on in the project, from the first sketches, it becomes clear that it can become a real architectural theme.

Could you give us an example?

Take, for example, the construction of a tower, which is intrinsically a very urban, architectural and aesthetic issue. If we wish to avoid cooling the tower in the summer and reduce its electrical energy consumption, designing a double-skin façade system allowing natural ventilation and passive cooling can become a very interesting topic of architectural thinking. If we approach the issue from this perspective, we begin to work simultaneously on its bioclimatic operation, composition, expression, constructive delicacy and contextualization, which change throughout the year. It represents a subject that is both demanding and exciting, which we faced while designing the Federal Statistical Office in Neuchâtel.

Another aspect on a similar topic: how can we reduce the energy invested in the construction of buildings?

The integration of local resources and materials requiring little gray energy also raises interesting architectural issues. Coupled with the growing demand for speed of construction, this theme encourages us to develop new building components and therefore new ways to design buildings. One of the fields of research and innovation, for example, consists of revisiting the industrial principles of prefabrication by introducing locally produced wooden elements, which benefit from the high level of expertise in this field in Switzerland. Swisswoodhouse, a modular home entirely built with wooden prefabricated elements and Microcity, based on hybrid forms combining wood and concrete, were born from these reflections.

Will sustainable housing design ever become universal?

No, and this for several reasons. The first reason is that the opposition between high-tech and low-tech has not been definitively resolved. In the 1970-1980s, there was a major debate. In fact, today, we work on non-dogmatic approaches, considering that there are custom-made hybrid solutions, which tend to an optimal matching of means, taking advantage of low-tech and high-tech solutions. That takes us away from the illusion of a universal answer to all questions.

Moreover, if we transpose the idea of "think global, act local" into architecture, sustainability involves seeking the most appropriate solution to climatic, urban, socio-economic and cultural local contexts. The principle of thinking of local solutions and acting with available means and resources probably leads us to think that there is no such thing as a universal solution. One need only find an adapted response to the context, and it will certainly not be the same in Zurich, Mexico City, Shanghai or Stockholm.

How can we deliver this perception to students?

There is no ready-made recipe to build sustainable architecture. However, it is possible to develop an approach whose modalities differ according to the specific nature of the project, while remaining part of a continuous philosophy. In my studio, students simultaneously learn architectural design and sustainability issues. We search for holistic approaches, where all partial solutions to the various issues constitute a whole, coherent and integrated at spatial level, and where the sum is greater than individual responses.

Therefore, the integration of sustainability issues represents a straight continuation of architectural approaches, which, in general, try to develop concepts transcending a set of constraints.

How can research invest this idea of sustainability?

We work simultaneously at the neighborhood, the building and the component scale. For example, LAST is currently involved in a research project entitled Living Shell. In this project, we aim to develop ways to raise existing neighborhoods and to reinvent a typology of housing which meets current needs, but can also be adapted, in the future, to new family structures. In fact, statistical projections reveal that households will be smaller than today, with more heterogeneous family structures and older people. To cope with this question, in the context of urban densification, the Living Shell project explores the idea of a lightweight construction system combining modules and components to suit a variety of situations. There would be load bearing parts which would remain permanent, while others could be transformed - more easily than in a traditional building.

What issues have to be dealt with for these projects to take shape?

Since more and more stakeholders are involved in projects, the development of a common culture is essential. This trend radically transforms both the practice of both architects and engineers. The architect has to work on the integration of these new stakeholders earlier in the project, in order to shift more effectively towards sustainability, while engineers must be ready to work in phases where it is not possible to calculate the data of each variant, but where one must be able to develop guidance, provide decision support and collaborate with subtle tradeoffs. If we do not implement this common culture, it will be difficult to integrate the complexity generated by all parameters into a project that is simultaneously coherent in terms of its concept, strong in terms of its expression and effective in terms of sustainability.

Why is this transition towards sustainable architecture taking so long?

There is the weight of habits, the "building as usual" attitude, which seeks to minimize operational and financial risks. This tends to slow down the development of innovative processes, which would promote the realization of real "integrated design". Exploring certain sustainability tracks is sometimes perceived as an increase of risks, despite the growing motivation of project owners and other stakeholders in the built environment. Therefore, this gap between risk minimization and the will to do something new needs to be filled. There is always a risk of being a pioneer, but if we develop a long-term vision, which is inherent to the concept of sustainable development, we realize that it is also dangerous not to evolve. Among other things, practices progress through best approaches and innovative projects, which demonstrate that other paths are possible. For example, the transformation of urban disused areas into sustainable neighborhoods, in which we have worked extensively, was perceived as very risky a decade ago. Today, this is much less the case, thanks to regeneration projects, which have shown the multiple benefits of this type of urban recovery. This can only encourage us to carry on with our research on the interactions between architecture and sustainability.

Translated from the French version of the interview by LAST.