Embodied and Construction Phase Greenhouse Gas Emissions of a Low-energy Residential building

Climate change is one of the biggest sustainability challenges of our time. In the context of the built environment, the emphasis is on increasing the energy efficiency of buildings, whereas other building life cycle phases are generally considered less important. However, in recent research it has been suggested that more attention should be given to construction phases, including emissions embodied in materials. They occur in early life cycle stages whereas a large share of use-phase related emissionsoccur outside the existingclimate change mitigation target years, and, due to development in energy sector,might significantly deviate from what is projected today. In this study, by using the life cycle assessment (LCA), we assess the greenhouse gas emissions related to the materials and construction of a low-energy multi-storey residential building in Finland. We depict how the emissions are allocated to the different building systems and look for opportunities to reduce the emissions from this perspective. The novelty of the study arises from two factors: (1) we utilize the wide assessment scope that enables depicting the importance of the boundary decision and (2) not many construction-phase LCA studies of modern low-energy residential buildings exist.