Field study evaluation of thermal comfort in air-conditioned buildings in a hot and humid climate with elevated space temperatures

Abstract

Buildings in hot and humid climates are typically operated and maintained at very low indoor air temperatures in the range of 22-23°C. With a view towards sustainable design and operation of air-conditioning systems, several countries in the tropical belt have begun to explore the possibility of raising the indoor space temperatures to 25°C and above. This thermal comfort study in a set of air-conditioned institutional buildings in Singapore was motivated when the space temperature set-points on its campus buildings were raised to 25°C towards the end of 2007. Seven offices across the campus were chosen in which objective measurements, such as temperature, humidity and air velocity were conducted. Occupants' responses were also solicited through a simple questionnaire survey. Whilst the results obtained were somewhat mixed, they clearly pointed in the direction that a significant percentage of the occupants did not experience optimal comfort levels in the air-conditioned environment. The findings suggested that increased air velocity could be an important consideration in warmer indoor environments.