Comparison of Material Compositions of Roofs in term of Environmental and Energy Performance

In world with limited amount of energy sources and with serious environmental pollution, interest in comparing the environmental embodied impacts of buildings using different structure systems and alternative building materials will be increased. The selection of building materials used in the constructions (floors, walls, roofs, windows, doors, etc.) belongs to one of the most important roles in the phase of building design. This decision has impact on the performance of building with respect to criteria of sustainability. The energy used in extraction, processing and transportation of materials used in building constructions can be significant part of the total energy used over the life cycle of building, particularly in nearly-zero energy buildings. The environmental impacts are expressed by indicators such as embodied energy (EE) from non-renewable resources, embodied CO2.eq emissions (GWP, Global Warming Potential) and embodied SO2eq emissions (AP, Acidification Potential) within system boundary from Cradle to Gate. The aim of analysis is to identify the environmental quality of material compositions for designed variants of roof constructions. The final values of assessments are compared by using methods of multi-criteria decision analysis.