Global Warming Potential as Key Performance Indicator to steer renovation strategies for the built environment

Abstract The 2050 climate neutrality target has to deal with the challenge of upgrading the existing, highly energy-intensive building stock into a highly efficient one. Long-term renovation strategies aimed not only at optimizing operational energy, but also at reducing embodied energy and carbon are needed to facilitate the transition to a low CO 2 emission. All measures adopted by the EU go in this direction and promote the use of indicators such as the Global Warming Potential (GWP) to quantify emissions from the operational phase and those embodied in building materials from cradle to grave. Material choice will play a key role. This paper analyzes the use of GWP as a Key Performance Indicator (KPI) to evaluate sustainability of building envelope renovations in relation to the materials used. In particular, GWP was used to compare the emissions associated with different solutions for insulating an existing wall to meet ZEB standards. The comparison was made between traditional thermal insulating materials and those made from recycled material, to highlight the benefits of circular design strategies that aim to reuse materials for the reduction of primary raw materials and waste. The GWP approach can be a useful decision support tool for designers, stakeholders and policy makers.