Comparison among different green buildings assessment tools: Application to a case study

The concept of green building plays a role of primary importance in the reduction of the use of resources, water, and materials, as well as on the reduction of impacts on human health and the environment, during the building lifecycle. A large number of countries has already developed energy certification procedures in order to rate the building energy performance; furthermore, a range of green building assessment tools and protocols has been developed in the past 20 years, with the aim of reducing energy consumption and the environmental impact in both the building construction and management phases. This paper compares the results of the application of three green building assessment methods on both the energy and environmental performance. Some of the most spread rating systems were chosen: Istituto per l'innovazione e Trasparenza degli Appalti e la Compatibilità Ambientale (ITACA, Italy), Comprehensive Assessment System for Built Environment Efficiency (CASBEE, Japan), and Green Star (Australia). The analysis was developed on a residential building located in central Italy, constructed by taking into account the international principles of sustainability and bioclimatic architecture. Starting from previous studies developed by the Authors, by which these protocols were compared and their scores normalized, the proposed study assesses the sustainability of the case-study building thanks to a point-based methodological approach. It is based on the identification of six common macro-areas that allow the homogeneous comparison of the three green building assessment tools. The study aims to assess the impact of these new normalized categories on the overall sustainability performance of the building.