A Nation Unprepared: Extreme heat and the need for adaptation in the United Kingdom

40 °C was recorded in the UK for the first time in July 2022 across the country. The UK Met Office predicts the UK could experience temperatures exceeding 40 °C every three years by the end of the century. There is limited data on how households cope and adapt to extreme heat. This research engaged with >1580 households across the UK through an online survey to explore household overheating challenges, their awareness of low carbon cooling technologies and how these challenges have changed over the last decade. Results show that the prevalence of indoor overheating reported in UK dwellings has increased from 20 % (2011) to 82 % (2022). While behavioural adaptations are still dominant, the use of air conditioners (ACs) has increased from 3 % in 2011 to 20 % during the last decade. If summer warming trends continue, our survey suggests, AC adoption is likely to increase, placing both a significant burden on electricity grid peak demand, and leading to economic inequalities, particularly among lower socioeconomic groups. It was also concluded that overheating experience is not solely reliant on building design and it can be influenced by range of factors including geography, dwelling type and household characteristics. Heat adaptation will require urgent policy to promote passive cooling strategies, enhance public awareness of heat risks and improve public communication to reduce heat related health impacts.