Patrimoine architectural du XXe siècle en Europe. Enjeux opérationnels et questionnements contemporains

In 1991, The European Council acknowledged the irreversible loss 20th century architectural heritage and recommended to each of its member states to begin intervening with a proactive course of action. More specifically, the council encouraged each state to implement strategies aimed at identifying, studying, protecting, restoring and raising awareness of 20th century architecture. After three decades, the time has come to take a step back and critically assess this situation in Europe.This second issue presents contributions that illustrate three different types of situations specific to 20th century architecture in Europe: The complexity of the controversies surrounding the work, the challenges of energy restrictions, the transgression of architectural icons and its limits. These contributions take a look at various case studies in which we find objects of material transformations subjected to political, technical and aesthetic debates from the perspective of experts, habitants, users or clients.The first part of this issue is concentrated on an architectural heritage which is rife with tension caused by its historic and social origins, on European, regional or urban scales. The second part casts a light on the concrete material issues which appear during renovations of certain modern architectures and on the types of innovation required to remedy energy inefficiency without altering the structures. Finally, the third and last part of this issue focuses on some perspectives concerning the legacy of great 20th architectural witnesses, the risks and possibilities created by renovation or adaption. Le Conseil de l’Europe établissait en 1991 le constat de pertes patrimoniales irrémédiables en matière d’architecture du xxe siècle et préconisait aux États membres de prendre en charge ce sujet de façon volontariste. Il les incitait notamment à mettre en œuvre des stratégies d’identification, d’étude, de protection, de restauration et de sensibilisation visant l’architecture du xxe siècle. Trois décennies plus tard, le moment est apparu opportun de prendre du recul et de procéder à un état des lieux européen à la fois critique et prospectif.Ce second numéro présente des contributions illustrant trois types de situations sensibles propres à l’architecture du xxe siècle en Europe : la complexité des controverses à l’œuvre, les épreuves de l’injonction énergétique, la transgression des icônes architecturales et ses limites. Elles s’intéressent à des cas d’étude var