The primary aim of this research was to assess the quality of the thermal environment of six Australian nursing homes, and to understand and quantify the impacts of the indoor thermal environment on the perceptions and comfort of staff, residents and other occupants. The impact of the thermal environment on perceptions and comfort of building occupants of six nursing homes was determined through: 1) a long-term building evaluation survey (staff members only); and 2) a point-in-time thermal comfort study, involving 322 residents and 187 non-residents. In addition, a combination of spot-measurements and long-term monitoring of indoor air temperatures was used to assess the overall quality of the thermal environment in the nursing homes. Results showed that some facilities did not provide a thermally comfortable environment for occupants through both summer and winter seasons, while results from the point-in-time study showed that residents preferred warmer temperatures (0.9°C) and generally wore more clothes than non-residents. The article also presents a discussion of the applicability of adaptive thermal comfort approaches to assessment of the indoor environment in nursing homes and differences between the perceptions/preferences of residents versus staff.