Retrofit attraverso pannelli prefabbricati: lo stato dell'arte

The aim of this paper is to provide an overview of the use of prefabricated panels in external building retrofitting. Building retrofit represents a pivotal point in terms of energy efficiency, as stressed by the European Directives EPBD 2002/91/EC, EED 2012/27/EU, 2009/28/EC, 2010/31/EU as well as by Horizon 2020, that also underlines the relevance of prefabrication as a primary retrofit strategies. Prefabrication can help overcoming the issues connected to traditional retrofit and provides advantages in terms of standardization in construction, a certain flexibility in architecture and the combination with conventional retrofit options; European projects, research works and architects designs have resulted in several proposals mainly focusing on residential context. The review of the state of the art shows several approaches in terms of prefabricated panels: large modules, small modules, structural steel modules and partially prefabricated modules. The main challenges are linked to design, fabrication, transport and installation: the classification is based on those parameters, identifying the most promising innovation fields to be further investigated. The building envelope represents a critical element to reach the 2050 decarbonisation goals; prefabrication in retrofit is expected to become a major tool to reach these goals. Some possible future developments are related to the thickness of the panel (linked to the use of innovative insulation material), and the adaptation in terms of finishing, dimensions and installation of the panel.