From efficient to sustainable and zero energy consumption buildings: Green buildings rating systems

The first evidence of the need of a sustainability concern dates to the 1970s, when the 1973 and 1979 energy crises showed the impossibility of making human development to rely only on nonrenewable energy resources. Such awareness was at the origin of the most widely accepted definition of sustain- able development, which is traced back to 1987, when the Brundtland Commis- sion, the United Nation’s World Commission on Environment and Development, proposed that “sustainable development is development that meets the needs of the present without compromising the ability of future gen- erations to meet their own needs” [1]. Sustainability is, therefore, a concept that embraces several fields and can be applied to widely different scales. A measure of sustainability is essential to compare different and competing alternatives when a selection of materials, energy resources, and production processes has to be performed [2]. In developed countries, a very large share of energy consumption (~ 40%) and CO2 emissions ( 30%) is due to buildings [3,4]. It is, therefore, quite nat- ural that over the years several green building rating tools have been conceived to assess the degree of sustainability pertaining to a building construction, oper- ation and, eventually, disposal, with the final aim of controlling and reducing their environmental impact. The earliest green building rating tool was estab- lished in the United Kingdom in 1990: the first version of the Building Research Establishment Environmental Assessment Method (BREEAM) for buildings. Soon after, the GBTool was released in 1996 by Natural Resources Canada, while the United State Green Building Council (USGBC) issued the first ver- sion of the Leadership in Energy and Environmental Design (LEED) rating sys- tem in 1998. Historically, the first type of labeling applied to buildings regarded energy efficiency. In Europe, for example, following the request by the Energy Performanceof Buildings Directive(EPBD), issuedbythe European Commission, each member country has to make mandatory the need of an Energy Performance Certificate (EPC) for the existing and new buildings. Energy efficiency in a build- ing is usually one of the most important ingredients [5] in the overall recipe that produces a green building label. However, energy efficiency and sustainability may be conflicting [6,7]. While energy efficiency labeling is mandatory, sustain- ability labeling is still mostly made on a voluntary basis. This chapter aims at describing the most important and widespread green building rating tools in order to develop a critical analysis, highlighting simi- larities and differences among them, and providing end users with useful guide- lines for applying sustainability procedures. The chapter structure is as follows. In the following section, the main fea- tures of the green building rating systems (GBRSs) are highlighted. In the sub- sequent section, a detailed description of eight international labeling systems is provided. Then, a comparison and a critical discussion of the similarities and differences among the analyzed rating tools are given. Finally, the conclusions are drawn.