Environmental footprint assessment of building structures: A comparative study

Following the failure to implement a rather sophisticated Excel-based environmental assessment tool, environmental load profile (ELP) in the Swedish construction industry, the City of Stockholm further developed a simplified version focusing on materials to make the tool user friendly and simple, aiming at educating stakeholders in the design phase of building construction. This study evaluated whether this simplified ELP of building structures (ELP-s) can be used directly or modified for use as a simple standard model for calculating the environmental footprint of building structures. ELP-s was compared with the two leading commercial LCA softwares, GaBi and SimaPro, based on two reference buildings: (i) a concrete and (ii) a wooden building, in order to examine the importance of material selection and the simplification of the tool. The results showed that the estimated energy footprint obtained using ELP-s was close in value to that produced by GaBi and SimaPro, but that carbon footprint was much lower with ELP-s. This great deviation in carbon footprint can be explained by the lower GHG emissions intensity per unit energy in Sweden compared with the world average or European average, the major data sources on which estimations in GaBi and SimaPro are based. These results indicate the importance of exercising care when applying commercial software tools to a specific situation in a specific country. They also indicate that the model should fit the purpose.