Insufficient sleep is known to have an impact on health, wellbeing, and productivity. Sleep has been explored extensively in the medical literature but has received scant attention in the built environment journals. With the climate becoming unpredictable, combined with the climate emergency and concerns over energy poverty, questions need to be asked about the suitability of the housing stock and, especially, bedrooms. This is pertinent for vulnerable individuals (e.g., very young, elder members of society, and those with medical conditions) who may be unable to adapt their sleep environment in extreme and prolonged heat events. The aim of this narrative review is to raise awareness of the complex inter-relationship between the sleeper and the bedroom in domestic properties. It highlights the vulnerability of sleepers and the need for adaptation strategies to cope with extreme heat events without resorting to mechanical air conditioning. It emphasises the need for interdisciplinary research to better inform stakeholders of the risks posed to sleep quality by climate change, and contributes positively to the promotion of health.