Thermal experience is deeply embedded in our everyday life. 'Hot', 'cool' and figurative references to other thermal states are commonplace in everyday discourse, underlining the importance of thermal environments to human existence. Thermal experience comes at an increasingly high cost since it usually requires expensive energy resources to create thermal conditions that meet householders’ expectations, in many hard-to-heat existing dwellings. Chris Tweed will talk about the role of thermal conditions in our experience of the built environment and the impact that thermally motivated behaviours have on energy used for heating dwellings in the UK.