Life Cycle Assessment of the European Building Stock – Assessing the transition towards a sustainable built environment

This PhD research aims at assessing the environmental impact of the existing European building stock and to reduce the impact thereof by proposing effective strategies and interventions. Reducing the environmental impact of the built environment along its entire life cycle is a crucial sustainability goal, which is translated in specific European Policies. Beyond the energy efficiency related policies, the construction and building value chain is one of the key area of intervention within other policy initiatives, e.g. the Circular Economy Action Plan. A model is developed that is representative for the European building stock, differentiating between various climatic zones, building typologies and technologies, building age and use. Data sources to feed the model are statistical databases, specific literature publications and sector regulations. The Life Cycle Assessment methodology is used to evaluate the environmental impacts and to create a dynamic model, sensitive to different market evolutions. The LCA model is used to investigate which interventions could improve the environmental performance of the building stock. This is investigated based on an LCA of various scenarios, determined by policy drivers and hot-spot analysis. As the operational energy of existing (older) buildings represents one of the main contributors to the overall impact, the operational energy use is studied in-depth through dynamic energy simulations and validated based on statistical data. Moreover, interventions related to achieving circular economy objectives are tested to evaluate their added-value and possible trade-offs. Finally, elements to make this LCA study of the EU building stock PEF compliant are identified. Indeed, PEF compliance could be important if the PEF method would be used at EU level as a monitoring system of the environmental impacts of buildings.