Improving the building stock sustainability in European Countries: A focus on the Italian case

COVID-19 pandemic has caused an economic crisis, and also the building sector has suffered consequences. Indeed, an increase in the building energy consumption, mainly in the residential sub-sector, was registered, due to higher energy use. European Union has enacted a strategic plan to combat this crisis by promoting environmental sustainability and giving a key role to the building sector. This study provides an overview of the implementation state from EU countries, of the European policies in terms of building energy efficiency and draws attention to the adopted financial programs and incentives to promote an energy-efficient built environment. It is shown that more than 70% of Member States have transposed the EU Energy Performance of Building Directives and all of them have activated plans or programs to finance the building energy renovation, mainly in the residential sector. A focus is made on the Italian case, by considering the recently introduced tax deduction of 110% (divided into a number of annual rates) that promotes specific energy efficiency measures for existing buildings, in the vein of new requirements provided by the Directive EU 844/2018. In this investigation, three residential buildings are selected, and, by employing both semi-stationary and dynamic approaches, a critical analysis of several passive and active energy efficiency measures is performed. The variability of climatic conditions and building markets are considered in energy and economic evaluations: the building case studies are located in different Italian climatic regions and have different construction ages. Considering the energy, environmental and economic indicators, it is shown how the new Italian funding program can boost the diffusion of energy efficiency interventions which imply the best energy performance, and not the best cost/benefit ratio. The study points out achieved goals, criticalities, and new perspectives after years of energy policies in Europe.