Depletion of natural resources, loss of biodiversity and global warming: so many global challenges to be met at the same time. According to the International Resource Panel, the global annual extraction of materials increased from 27 billion tonnes in 1972 to 92 billion tonnes in 2017. In Europe, the construction sector is one of the largest consumers of resources, with half of the raw materials extracted, half of the energy consumption and a third of the water consumption… not to mention the impact on land.
This is how the law of 17 August 2015 relating to energy transition for green growth had set the objective of recovering 70% of construction waste in material form by 2020. The law of 10 February 2020 relating to the fight against waste and the circular economy (AGEC) has reinforced this objective by emphasizing sorting, reuse and recovery. The players in the construction industry are thus fully involved with the establishment of an Extended Producer Responsibility (EPR) sector for construction products and materials (PMCB). Beyond the difficulties associated with all PWRs, the key issue of deconstruction operations is definitively confirmed. Deconstruction is thus fully in line with circular economy approaches, avoiding waste and better managing the end of life of products, equipment and materials.
It is no longer a question of demolishing, but of deconstructing... to rebuild with materials from deconstruction. It is a whole sector that is invited to radically rethink its vision of the act of building: techniques implemented, choice of materials, modularity of spaces, reversibility of buildings... The challenge is to optimize "from cradle to cradle” the life cycle of buildings. Thinking LCA (life cycle analysis) of the building becomes a necessity all the more relevant since, according to the Ellen MacArthur Foundation, 10 to 15% of building materials would be wasted during construction and 54% of demolition materials put in installation waste storage.
At a time when planetary limits are more and more present and when the war in Ukraine leads to awareness of the scarcity of resources, in particular by a significant increase in construction costs or an extended supply period, deconstruction is a common sense response to which our societies must return.
