For more than a decade, the Walloon government develops plans of economic redeployment; among them, the “Marshall Plan” financed (from 2009 to 2013) the “Reno2020” project, which general objective was to demonstrate that the existing Walloon residential stock provides a vast potential for improvement, especially as far as energy and environmental performance is concerned. Furthermore, this project involved different actors of the construction sector social microcosm: - The client, private or public owner of dwellings to be renovated. - The architect, author of the renovation project. - The contractors, transferring projected renovation into reality. - The material producers, developing ad hoc solutions to particular problems. - The scientific committee, composed of the Belgian Building Research Institute (BBRI, Sustainable Renovation Department), the Technical Control Bureau for Construction (SECO) and University of Liege, Energy and Sustainable Development (EnergySuD) research unit. ; Réno2020 : Méthodologie de développement et d’insertion des nouvelles technologies dans la rénovation durable du logement wallon