The footprint of a habitat
The quest for lightness is not new. The ambition to reduce the quantity of material began a century ago in a context of a shortage of housing and materials. With the urgency to build more and the obligation to consume less, some pioneers are inventing other architectures. Their names are Richard Buckminster Fuller, Charlotte Perriand, Pierre Jeanneret, Albert Frey, Lauwrence Kocher, Walter Gropius, Konrad Wachsmann, Jean Prouvé, Charles and Ray Eames, Makoto Masuzawa, Jorn Utzon ... 'un habitat' analyzes some thirty of these experimental architectures carried out between 1920 and 2020, which bear witness to the evolution of light construction in industrialized countries.
Economy of means, speed of implementation, modularity, flexibility and scalability ... these qualities inherent in lightweight construction are now combined with ecological ambitions of frugality: control of the life cycle, energy autonomy and reduction of greenhouse gas emissions. tight. Designed by Renzo Piano, Werner Sobek or Shigeru Ban, from Paris to Tokyo, contemporary lightweight architectures explore modularity, participatory construction or miniaturization. They are based on the conviction that building, in conscience, lighter requires less material, uses less resources, produces less waste, requires less assembly time, requires less space, requires exponentially less energy. , symmetrically reduces the carbon footprint of building a home.
This study, carried out on around thirty international projects, reveals the potential and the diversity of the construction systems developed. It testifies to the capacity of these architectures to adapt to the techniques and expectations of their time. Each exploration, re-read in its historical context from archives, films, models presented in the exhibition, reflects an approach, a technique and a way of living. Redesigned and broken down according to a protocol developed for this event by the Philippe Rizzotti Architecte agency and the IBI laboratory of ETH Zürich, the corpus reveals correspondences and shared qualities. This inventory makes it possible to quantify the constructions, compare the materials, analyze the assemblies and classify all or part to bring out adaptable logics in the future.
Presented chronologically around the 8x8 BCC “all wood” house - designed by Jean Prouvé and Pierre Jeanneret and loaned by Galerie Patrick Seguin whose elements serve as a standard, the analysis also offers for the first time the opportunity to highlight regarding the estimation of masses, components, construction systems of buildings and their carbon footprint, to compare them with each other and with conventional constructions. The edifying results systematically turn to the advantage of lightweight architectures. The average mass per square meter of the houses presented does not exceed 300 kg / m2 when the current pavilions easily reach 1200 kg / m2. Their corrected average carbon footprint is estimated at 282 kg CO2.eq / m2, while the target of the new regulations is 640 kg CO2.
At a time when the building must reduce its consumption of resources and faced with the negative externalities it generates during its manufacture, its weight reduction opens up a formidable field of application that is quick to implement, consolidated by a known, referenced and now analyzed. The quest for lightness seems all the more fundamental as the transformation of our manufacturing processes would instantly reduce emissions from new buildings by 50% even before they are inhabited, while integrating the objectives of reducing energy consumption and offering material deposits for the future.