Climate change and indoor temperature variation in Venice buildings: the role of density and urban form

Despite the influence of urban form on microclimate and building thermal processes has been acknowledged, few studies have addressed the influence of overheating mechanisms on heterogeneous urban fabrics for existing historical cities. This study investigates the impact of changing urban climate on indoor temperatures by focusing on three Venice morphological patterns. Through microclimate modelling techniques, outdoor and indoor temperatures are simulated in 2020 and 2050 scenarios. Results show that the compactness of the urban fabric contributes to reducing indoor building temperatures. The analysis suggests that the increased density of shadow areas can mitigate the outdoor temperature values and reduce direct radiation on façades. When comparing the two climate scenarios 2020 and 2050, average indoor temperatures grow in the latter. However, the analysis highlights that the absence of insulation and the relatively high thermal mass of the typical Venetian envelopes plays a crucial role in the building thermal processes preserving indoor comfort in a warmer climate future.