An overall methodology to define reference values for building sustainability parameters

tThe paper presents a methodology to define reference values regarding building environmental impacts,energy outputs, and global costs. Four exemplary Italian residential categories were analyzed, focusingon the recent existing stock and on the most common kinds of houses. Buildings were subjected to LifeCycle Assessment (LCA) analyses, through SimaPro software, in order to define specific values linkedto the environmental impacts and to the total energy spent. The amount of energy related to the usephase, including heating, domestic hot water, and cooling systems, was estimated by using the energysimulation program EnergyPlus. Building economic performance was analyzed through Life Cycle Costing(LCC) analyses, with the global cost approach. The results showed that the use phase implied the largestcontribution to the environmental and energy impacts; instead the pre-use phase was predominant inlife cycle costs. Furthermore, since a considerable amount of consistent data was used for this study, theoutcomes could be treated as reliable for the definition of benchmarks. For instance, the results indicatedthat, during the whole life cycle, Italian residential buildings could spend around 140 kWh/m2, with aproduction of about 35 kg CO2eq/m2each year, reaching a global cost of nearly 1420 D/m2.