Greenery systems for urban sustainability: State of the art and perspective in Italy

Abstract

The inclusion of greenery in our cities is a key factor for sustainability. Considering the shortage of green urban areas, building can play a positive role itself: through the inclusion of greenery systems (GS) such as green roofs and green walls, the building envelope can act as a multiplier of urban green surface. Nevertheless, despite the benefits achievable, GS implementation in the Italian context is still poor. The aim of this study is to produce the Italian state of art in terms of appreciation and promotion of GS solutions as urban quality agents and, on the other hand, in terms of the residual barriers to their spread. This framework can be used as a knowledge base for actions to encourage the adoption of GS in Italian cities. To this end, the study was carried out in three steps: review of GS benefits at urban scale; assessment of the Italian incentives for the GS diffusion; analysis of the current barriers to GS diffusion in the Italian context. The results show an extensive list of achievable benefits at the urban level (e.g. reduction of heat island, rainwater management, etc.) and their recognition in the Italian policies. Nevertheless, the study highlights a shortage in promotion tools, such as tax breaks, and the persistence of barriers to the GS spread (cost’s gap between GS solutions and traditional; poor diffusion of GS technological culture). A greater commitment is hoped both in proposing effective incentives, both in a joint effort between administration and research in assessing benefits in relation to local needs and in spreading the technological culture of GS among professionals and consumers.