In light of the high energy consumption associated with Heating Ventilation and Air Conditioning (HVAC) in tourism accommodation establishments, as well as the concern for guests’ satisfaction which limits the environmental actions of these establishments, this study tests the hypothesis that thermal comfort is socially constructed, and as such, social norms will be effective in influencing HVAC consumption towards more sustainable levels. Within the framework of a randomised field experiment, the response of hotel guests to message prompts to set their room thermostat to a prescribed temperature is observed. Response behaviour is monitored using Temperature data logging devises place in the rooms. Findings suggest that social norms are effective in influencing hotel guests’ room temperature settings, indicating that thermal comfort is largely socially constructed. The implication of this is that the future of the current unsustainable trend in resource consumption and Green House Gas pollution, driven by the increasing adoption of, and demand for, HVAC systems in buildings, can be modified towards more sustainable levels. The application of the behavioural intervention to testing the social construction of thermal comfort, as well as the technology adopted for observing behaviour, are a novel contribution to the existing body of knowledge.