Despite being one of the key mechanisms via which people are exposed (or not) to uncomfortable or dangerous ambient environments—the conditions of the air or other medium that surround us—housing is rarely considered in evaluation of future climatic changes and vulnerability, including extreme summer heat. Responding to increasing interest in futures across geography—particularly in a warming world—this paper conceptualises and analyses localised heat-housing trajectories for neighbourhoods in England and Wales. We apply sequence analysis to projected climate data to identify and characterise common trajectories of extreme summer heat. Heat trajectories are juxtaposed with housing data for ~15 million individual properties detailing type, quality and characteristics, derived from Energy Performance Certificates, as well as other socio-demographic data. Our approach is deliberately somewhat ‘speculative’—a rehearsal spaces of sorts for different ways of responding to the prospect of uncertain futures. This enables us to consider different vulnerabilities that are likely to be reinforced, produced or remediated by extreme summer temperatures. Our heat-housing trajectories highlight the important role of precarity in shaping vulnerability to extreme summer temperatures, a dimension underexplored to date. We also reflect on how we can conceptualise and map uneven ambient futures within the constraints of existing quantitative spatial data.