Embodied Environmental Impact from Built Environment Development–Focus on Buildings

摘要: Buildings are the key components of urban areas and society as a complex system. Traditionally, the emissions embodied in construction materials have not been considered important, in comparison with impacts from the energy use when it comes to mitigating the climate change impact of buildings. Moreover, evaluating the environmental burden of construction materials has proven problematic and the reliability of the reported impact estimates is questionable. Following the multiple case study approach, four different single-case life cycle assessment (LCA) studies were conducted in this dissertation to contribute to filling this gap. Based on the results, the LCA approach can improve the understanding of the environmental impacts of different construction materials. Another key contribution is about the share of transport in initial embodied impacts, often not explicitly considered forming a weakly understood uncertainty factor. Yet, the results should be interpreted cautiously. The first concern relates to the selected LCA database for the assessment that can result in very different evaluation in almost all impact categories, with climate change and fossil depletion as the only exceptions (yet with some inconsistency in them as well). The other issue is linked to the uncertainties surrounding the input data (selection of material from the database and the method) as well as the uncertainties in the sequestration capacity of a few specific materials (compressed straw, reed panels, and wooden elements). It was clear that the assessment depends heavily on those input data and sequestration capacity assumptions. Thus, the study revealed that extensive …