Residential adaptive comfort in a humid subtropical climate—Sydney Australia

Abstract

The aim of this study was to apply new technological survey capabilities to a field setting that is underrepresented in the thermal comfort research literature, namely the residential setting. Indoor temperature readings from autonomous datalogging devices (iButtons) were combined with simultaneous and contiguous subjective thermal comfort assessments via personal smartphones. Householders’ spatio-temporal patterns of A/C usage, indoor and outdoor thermal environmental parameters, right-here-right-now thermal comfort perceptions and adaptive comfort behaviours were recorded. The longitudinal research design included a sample of 42 homes who were polled intermittently across a two-year monitoring period in which a total of 4867 A/C usage events and 1525 online comfort questionnaires were logged. Based on the right-here-right-now thermal sensation votes, the householder samples’ neutral residential temperature was estimated to be about two degrees lower than that predicted by the ASHRAE Standard 55′s adaptive model for office occupancies. Despite the lower-than-expected neutrality, comfort zone widths for 80% acceptability were found to be 9K in the Sydney residential setting, which is 2K wider than prescribed in the adaptive model for office occupants. These findings suggest that people in their homes are more adaptive and tolerant of significantly wider temperature variations than their counterparts in office settings. An adaptive model that can be used for the assessment of residential thermal comfort is proposed.