The general and specialized press recently reported on the problem of stockpiling millions of tonnes of “ground waste” each year from construction sites in the Paris metropolitan area, to which, since May 2016, land has been added. extract linked to the digging of the 200 km of the Grand Paris Express. The challenges and the advantages brought about by this observation suggest that this gigantic project, open at least for the next twenty years, can - and must - offer the opportunity to invent the "lever for a rebalancing" likely to ensure optimal recycling which will recycle these so-called “scrap” extracted from the ground and up to now landfilled.
Paradoxically, raw earth has been a universal building eco-material for over 10,000 years. A third of humanity today lives in earthen buildings, and France is full of architectural heritage built in earth for centuries and still inhabited. France is also internationally recognized as being, for three decades already, a driving country regarding knowledge and know-how in raw earth construction. Research, teaching and constructive and interdisciplinary knowledge are in continuous development. For the past ten years, knowledge of the matter in grains and clays has thus enabled considerable scientific advances, as well as the mastery of new manufacturing and implementation techniques. Recent innovations relating to light earth, composite earth panels, interior and exterior plasters, unstabilized poured clay concrete, precast adobe technique or 3D printed earth are the most obvious milestones and guarantors of a promising future.
Like wood, stone or plant fibers, the earth also has tremendous ecological and social virtues. It has a very low carbon footprint; it is completely biodegradable if it is not stabilized; it is 100% healthy and free of volatile organic compounds; it is breathable, regulates humidity, indoor temperature and has a high inertia. The earth is especially rewarding for builders and offers surprising haptic qualities linked to its materiality.
This unprecedented "alignment of planets" allows us to present, in this publication and the exhibition it accompanies, an experiment in building materials for architecture based on the re-use of a local and manifestly under-used resource - the " Terres de Paris ”and its region - with the ambition of making it a new urban material, both innovative and sustainable. This experiment is a stage point in an ongoing research that we wish to pursue in association with partners in the sector who wish to join us. The approach is not exhaustive. It aims to enrich the debate on the use, in architecture, of this little-known material, wrongly discredited because it is perceived as waste. A virtuous material which allows you to build, of course, but which above all offers the possibility of embodying a truly sustainable relationship with the world.
TERRES DE PARIS, FROM RESOURCE TO MATERIAL
Exhibition - Experimentation at the Arsenal pavilion
Facing the mountains of earth excavated each year in Ile de France - several tens of millions of tonnes - for the realization of current sites, Serge Joly & P.E. Loiret, exhibition curators, associated with the amàco research center and the CRATerre laboratory -Ensag, proposed to the Pavillon de l'Arsenal to experiment the use of this abundant natural resource for the construction of contemporary raw earth buildings in urban areas.