The Thermal Sensitivity of the Elderly in Public Outdoor Open Spaces in Hong Kong Public Housing Estate

The aging population and limited public outdoor space (POS) in Hong Kong present challenges for maximizing the utilization of these spaces and ensuring comfort, particularly during the intensifying heat stress in summers. Previous research focused more on studying outdoor spaces in parks, while outdoor areas in close proximity to elderly residents, considering their limited mobility, warrant greater attention. This study investigates the thermal sensitivity of the elderly in outdoor spaces with different functions in Choi Hung Estate (CHE) and Upper Ngau Tau Kok Estate (NTKE), utilizing weather data, passive observations, and questionnaire surveys. The findings reveal variations in thermal sensitivity among the elderly in different types of outdoor spaces, the thermal threshold has a 5°C mPET difference between exercise area and rest area. Moreover, the function of the "Exercise" significantly increases the probability of elderly residents visiting the POS, with a 100% increase in CHE and a 61% increase in NTKE.