Effect of external ground surface materials on indoor thermal comfort

External ground surface materials produce enormous heat output and thus raise outdoor temperature, as well as reflecting solar radiation and creating long wave radiation that enters indoor areas via windows and increases indoor temperature, and thus influence occupant comfort. Using a field experiment and questionnaire study, this study examined the influence of external ground surface materials on indoor thermal comfort. Experimental results indicate that the subjective and objective thermal comfort evaluation of classrooms with greenery outside is better than that of those with concrete outside. External ground surface material thus physiologically and psychologically influences indoor thermal environment.