Changing Cities for Resilience against Climate Changes: Architectural, Engineering and Human Health Implications The H2020 Project HARMONIA

Climate changes are inducing consistent variations in the “actions” that are normally considered in design of buildings and more in general in Risk Analysis for urban environments. Extreme winds gusts, Heat Islands and Waves, instant flash floodings and thunderstorms are representing a natural phenomenon that become more and more frequent across Europe, causing large economic damages as well as human lives losses. The Architects & Engineering Community response, to try to improve the Cities’ resilience toward such “Extreme Actions” is inducing a global “re-thinking” of Urban Environments, introducing several innovative solutions to increase the inhabitants’ well-being and capability to cope with these threats. One of these strategies is the introduction of Green Vertical Walls as façades of buildings, a technology that, most probably, will in the next future at least partially replace the technology of the curtain-wall façades made by steel and glass. However, a massive introduction of this very promising technology is, currently, partially prevented by several uncertainties related to some issues of different types: technological (e.g., interaction of the green wall with the building existing façade and the risk of mould growth), structural and mechanical resistance (e.g., drag force due to tangential action affecting the green features such as branches and leaves) and Health Safety (e.g., increment of PMs during the blooming season). This paper (based on experimental results of some pilot study carried out at Politecnico di Milano) tries to summarize the main advantages and disadvantages of this technology, while introducing the H2020 European Research Project HARMONIA, which is dealing with Climate Changes and, in accordance with the approach of Vulnerability Assessment and Risk Management, aims at providing hazard indicators that can help policy makers and increase the citizens awareness.