Twentieth International Conference on Environmental, Cultural, Economic & Social Sustainability

Abstract

Green infrastructures and inherently green roofs (GRs) play a key role in increasing cities’ resilience to climate events, such as heat waves and flooding, while also improving the building’s thermal performance, which makes the GRs aligned with the Sustainable Development Goals (SDG) of the 2030 Agenda, especially SGD 11 (Sustainable cities and communities) and 13 (Climate action). While many studies have evaluated the environmental performance of GRs using the Life Cycle Assessment (LCA) methodology, the most environmentally friendly GR has yet to be identified. This work encompasses the environmental results from a systematic literature review regarding LCA studies on GRs, identifying the differences between GR types. This work identifies the main trends in methodological choices, including functional unit, system boundaries, multifunctionality, and sensitivity analysis, and enables the understanding of their effect on the environmental sustainability of GRs, namely in the most evaluated impact category - climate change (CC). This study shows that extensive green roofs are the most addressed and that the manufacturing stage of insulation layer materials is the hotspot for the environmental impacts. CC results varied from 3.08 kg CO2eq to 155.88 kg CO2eq, and no correlation between the GR type and the one with the best environmental performance could be identified. Future research should focus on evaluating GRs sustainability, considering the GRs specificities and benefits, to enable the widespread application of GRs to create sustainable and resilient cities.