Life-cycle assessment of residential buildings in three different European locations, case study

The paper presents the comparative results of the life-cycle assessment (LCA) of one residential building with two constructive systems in Brussels and one steel frame house located in three different European towns: Brussels (Belgium), Coimbra (Portugal) and Luleå (Sweden). In a recent study, a modular building was studied in Coimbra and Luleå. It was shown that in terms of CO2 emissions, the Use Stage was the most harmful stage during the building life-cycle for Coimbra climate. Contrarily, in Luleå, it was the Product Stage, despite energy consumption being higher than Coimbra, due to the way electricity and heat are generated. In the present study, two structural systems are first compared for the Belgian house: steel frame and traditional masonry. A different life-cycle scenario is taken into account for the steel frame house for the three different locations, in which the monthly temperatures, energy mix, heating and cooling systems are defined. The LCA is carried out using the basic tool described in the companion paper. It is worth recalling that the results obtained with the basic tool were verified against Pleiades+Comfie and Equer software, enabling to carry out a complete LCA, for Brussels. Our results confirm that for all the three climates, the Use Stage (Operational energy) is the most harmful period during the building life-cycle and that the energy mix of the country strongly influences the equivalent CO2 emissions related to the Use Stage (Operational carbon) and may entirely reverse the conclusions about the life-cycle carbon footprint of the building.