Ventilated façades can help to reduce summer building thermal loads and, therefore, energy consumption due to air-conditioning systems thanks to the combined effect of the solar radiation reflection and the natural or forced ventilation into the cavity. The evaluation of ventilated façades behavior and performance is complex and requires a complete thermo-fluid dynamic analysis. In this study, a computational fluid dynamic (CFD) methodology has been developed for the complete assessment of the energy performance of a prefabricated timber–concrete composite ventilated façade module in different operating conditions. Global numerical results are presented as well as local ones in terms of heat flux, air velocity, and temperature inside the façade cavity. The results show the dependency of envelope efficiency on solar radiation, the benefits that natural convection brings on potential energy savings and the importance of designing an optimized façade geometry. The results concerning the façade behavior have been thoroughly compared with International Standards, showing the good accuracy of the model with respect to these well-known procedures. This comparison allowed also to highlight the International Standards procedures limits in evaluating the ventilated façade behavior with the necessary level of detail, with the risk of leading to design faults.

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The frequency and intensity of extreme weather events have increased in the last few years. Buildings resiliency against natural hazards (hurricanes, flooding, wildfires, etc.) is fundamental for the adaptation to climate change, however it is hardly included in their design. Buildings exposed to extreme climate conditions may become drivers of vulnerability, rather than providing shelter for users, leading to human and economic losses. The building stock assessment appears to be quite detailed about seismic vulnerability and energy demand related to climate change, but not towards other hazardous events, such as extreme winds. Furthermore, climate data provided by current standards and used for building design need to be seriously reconsidered, since they no longer represent the real weather variables. During windstorms, the main threats are mainly due to the detaching and flying of materials and elements from buildings and urban furniture. The chapter deals with the effects and consequences of strong wind events on the built heritage and calls for an urban transition to create resilient and safe environments for the people. An overview of the current standards related to building design against wind is presented, and mitigation and adaptation strategies are proposed to respond to current and future climate threats.