Green walls as nature-based solutions for urban and building resilience: a case study.

The Nature-based solution concept builds on other closely related concepts, such as ecosystem services, resilience, green infrastructures. Green walls (or Living Walls) can be considered natural based solutions with environmental, social and economic positive effects on buildings and, if widely applied, on cities, as demonstrated by the scientific literature. Moreover, different international guidelines drive EU countries to use green walls as a sustainable strategy to resilience of buildings and cities. These guidelines underline four fundamental aspects to consider: the designing, the installation, the plant species selection and the maintenance. Through the description of a case study in Turin (I) - an intervention on an existing building located in the city center - the paper focuses on the above-mentioned aspects, from technological to agronomic point of view. The paper deals with the objectives of the project, the design phase (analysis of the building/support structure and site), plant selection (ecological needs, aesthetic and functional aspects), the installation (frame, vegetated panels, irrigation system), the monitoring and maintenance activities (water supply needs, pruning per year, replacements), and highlights the quantitatively and qualitatively performance of the green wall. The paper includes a discussion about the potential of this technological solution for urban resilience.