Nowadays, buildings are increasingly seen as a pressing environmental problem. By their very nature, they affect and transform the land on which they are built by changing and destroying habitats and causing loss of biological diversity. On a macro level, buildings contribute to deforestation, natural resources depletion, the risk of global warming, stratospheric ozone depletion, overuse of water and acid rain by their enormous materials and energy consumption. In order to effectively improve the ecological performance of buildings, it is important to know in which life phase (the construction, the use, the refurbishment or the disposal) which environmental impacts occur and why. The aim of this work was to perform a Life Cycle Assessment (LCA) on a set of buildings obtained from the BKI -the German “centre for construction costs”- to assess which life phases and elements require particular attention during the effort of reducing the environmental impacts in the building and construction sectors. The LCA method allows a holistic assessment, considering the whole life cycle of a building. This avoids problems in shifting from on phase to another.