The aim of this study is to appraise the environmental impacts generated by a building designed for sustainability. The prefabricated building has 50 years lifetime. The construction takes place in Germany. The design is per-formed in a way to construct the building with materials having high circularity potential. Timber is used as the main structural material. Clay board panels that recyclable are used in the interior walls. Functionality and the use of as many materials as possible were considered in the design of the building. Life cycle assessment methodology is followed according to ISO 14040–ISO 14044 Standards. Therefore, goal and scope definition; inventory analysis; impact assessment; and interpretation steps are performed. CCalC2 (Carbon Calculations over the Life Cycle) tool is used for life cycle assessment modelling. The impact categories investigated are as follows: identifying the global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), ozone layer depletion potential (ODP), photochemical smog potential (POCP) and human toxicity potential (HTP). System boundaries cover construction, usage and demolition phases. The assessment of building life cycle environmental sustainability is important for determining the construction sector's future vision.