Investigation and optimization of outdoor thermal comfort in elementary school campuses: Example from a humid-hot area in China

The elementary school campus is the primary location where children both learn and live. The school environment significantly impacts children's health and well-being. While today's primary school campus designs generally adhere to regulations, they may still offer an unsafe thermal environment. To address this concern, we conducted a thermal sensory questionnaire in a representative outdoor space of an elementary school campus in Guangzhou, China. The thermal comfort of children was assessed using the Universal Thermal Climate Index (UTCI). Additionally, to enhance the thermal environment of current primary school campuses, we conducted a tree landscape preference survey. Based on children's thermal benchmarks and plant landscape preferences, a bioclimatic design for outdoor activity spaces on primary school campuses in humid-hot areas is proposed. The results show that: (1) Air temperature and mean radiant temperature are the main meteorological factors affecting children's thermal sensations in summer; (2) The outdoor neutral UTCI of male and female children is 25.0 and 22.8 °C, respectively, and the acceptable UTCI is 29.7 and 27.1 °C, respectively; (3) With respect to landscaping, children prefer large trees and evergreens planted in a plant community or singly. Their weighted preference scores were 3.10, 2.63, 2.27 and 1.89 respectively; and (4) Based on children's thermal benchmarks and plant landscape preferences, a tree-planting design strategy for primary school campuses in hot and humid regions is proposed. This study provides valuable advice for architects and landscape planners with respect to the design of elementary school campuses.