Heat Stress Dichotomy: Long-term Adaptation and Acute Shock in London Domestic Environments

Europe is consistently experiencing hottest summers. Understanding people's thermal comfort and stress and responses to heat waves has become increasingly important. While much of the literature has recognised the overheating risks in the UK's domestic housing stock, there remains a gap in analysing residents' indoor heat exposure during heatwaves. This research aims to investigate the mini heatwaves occurring in domestic environments, evaluate the consequences of chronic and shock heat that residents face due to climate warming, and explore the factors influencing residents' responses and adaptive capacities to heat waves. A sensor-enhanced housing survey data was collected in Southwark, London, over two summer months of 2023 during when a mini heatwave event. This study integrates outdoor weather data, sensor-measured high-resolution indoor environmental conditions, the Index for Multiple Deprivation and building features to analyse indoor heatwaves and thermal comfort. This article breaks ground by advancing existing discussions of urban heat stress, which typically focus on outdoor environments, by specifically examining indoor chronic and shock heat exposure intensities and the associated risks due to vulnerability from asymmetry in adaptive capacities. Additionally, the article aims to re-define the current heat wave classifications based on the domestic heat waves experienced by residents.