Post occupancy evaluation of thermal comfort and indoor air quality of office spaces in a tropical green campus building

Abstract

Purpose As suggested in many previous studies, good thermal comfort and indoor air quality (IAQ) played a significant role in ensuring human comfort, health and productivity in buildings. Hence, this study aims to evaluate the thermal comfort and IAQ conditions of open-plan office areas within a green-certified campus building through a post occupancy evaluation. Design/methodology/approach Using the field measurement method, environmental dataloggers were positioned at three office areas during office hours to measure the levels of thermal comfort parameters, CO2 concentrations and the supply air rates. At the same time, questionnaires were distributed to the available office staff to obtain their perception of the indoor environment. The findings were then compared with the recommended environmental comfort ranges and used to calculate the thermal comfort indices. Findings Results show that the physical parameters were generally within acceptable ranges of a local guideline. The neutral temperature based on the actual mean vote at these areas was 23.9°C, which is slightly lower than the predicted thermal neutrality of 25.2°C. From the surveyed findings, about 81% of the occupants found their thermal environment comfortable with high adaptation rates. A preference for cooler environments was found among the workers. Meanwhile, the air quality was perceived to be clean by a majority of the respondents, and the mean ventilation rate per person was identified to be sufficient. Research limitations/implications This study focussed on the thermal environment and air quality at selected office spaces only. More work should be carried out in other regularly occupied workplaces and study areas of the green educational building to allow a more thorough analysis of the indoor air conditions. Practical implications This paper highlights on the thermal comfort and air quality conditions of the air-conditioned office spaces in a green-certified campus building and is intended to assist the building services engineers in effective air conditioning control. The findings reported are useful for thermal comfort, IAQ and subsequently energy efficiency improvements in such building type where adjustments on the air temperature set-point can be considered according to the actual requirements. This study will be extended to other green campus spaces for a more exhaustive analysis of the indoor environment. Originality/value There is limited information pertaining to the environmental comfort levels in offices of green campus in the tropics. This study is, therefore, one of the earliest attempts to directly explore the thermal comfort and IAQ conditions in such workplace using both on-site physical measurement and questionnaire survey.