THE ENVIRONMENTAL RELEVANCE OF THE CONST RUCTION AND END-OFLIFE PHASES OF A BUILDING: A TEMPORARY STRUCTURE LCA CASE STUDY

LCA can prevent shifting the environmental burden of a building to peculiar life cycle phases. Components production and demolition stages became much more relevant in new low-energy buildings. The same applies also to temporary structures, whose useful service life is generally limited to the duration of the related event. More attention must therefore be paid to the choice of the construction materials and the way they are assembled in order to reduce resource depletion, embodied energy and waste production. To achieve this goal, it is essential to act in the design phase of the building in order to include environmental problems in the early stages of the decision making process. The objective of our study is to assess the environmental impacts of the different life stages of a temporary structure to support the design phase of future ones. The reference case study is the Brazilian pavilion constructed in Milan (Italy) for EXPO 2015. The aim of the research is to evaluate how much the design phase of the building, the choice of the materials and the end-of-life scenarios can influence the environmental performances of the structure. Primary data for the whole lifecycle are considered and a sensitivity analysis on the materials sustainability is performed. LCA results confirm the importance of the design phase for temporary structures. The predilection of natural and recycled materials in the construction phase and the prevision of a second life significantly reduce the impacts of the building. Among the end-of-life scenarios the best environmental solution proves to be the refunctionalization on site. The priority must be therefore to foresee a second life of the components at an early stage of the decisionmaking process. Similar conclusions could be expected for low-energy buildings too.