Improved sustainability certification systems to respond to building renovation challenges based on a literature review.

Given that building stock plays a crucial role in achieving long-term sustainable goals and in meeting Europe's climate targets, appropriate resources are needed to transform the sector and increase the rate of sustainable renovations. Considering the key role that sustainability certification systems (SCSs) such as LEED or BREEAM have played in making sustainable new buildings more commonplace, we assume that accurately assessing the performance of existing buildings is vital to support this transformation. In this study, a semi-systematic literature review was designed and conducted to improve current evaluation instruments to ensure matching the real needs and attributes of existing buildings. Scientific and ‘grey’ literature were analysed to build on previous knowledge of the two areas under study: built environment and evaluation instruments. These areas were jointly analysed, linking scientific knowledge with professional constraints, by exploring four key topics: sustainability challenges of the built environment; building renovations; sustainability support instruments; and SCSs. We have identified shortcomings in current evaluation instruments and provided insights to improve SCS schemes for existing buildings so that they can be tailored to buildings' specific circumstances and catalyse renovations. Our reflections on how to properly measure sustainability of existing buildings can contribute to responding to the building-stock challenges.