Theoretical fragility curves − A novel approach to assess heat vulnerability of residential buildings

Abstract

Extreme weather events, including heatwaves, are escalating with the changing climate. High outdoor temperatures increase morbidity and mortality. Heat vulnerability indices (HVIs) tend to neglect or only simplistically consider the impact of the building in their analyses. This research aims to implement the reliability analysis used in other fields of civil engineering to study the overheating of buildings. In this method, the internal temperatures in different building types are determined with dynamic simulations. These results are used to create fragility curves. Historical weather data has also been used to produce the hazard curve. With these two, the overheating probability of buildings in a city can be analysed. Based on the methodology, the vulnerability of a district of Budapest was investigated as a pilot area. From the results, it can be seen that precast concrete panel buildings are the most vulnerable, while the least vulnerable category is the single-family house for an average internal temperature limit of 26 °C. In a sensitivity analysis, adaptation measures such as shading and enhanced natural ventilation uniformly reduced the overheating probability of the panel building. The methodology developed here makes it possible to incorporate the overheating of buildings more objectively in heat vulnerability analysis.