Key factors of occupants' behaviour characteristics and indoor air quality perception on occupancy comfort in multi-storey residential buildings in Thailand

This questionnaire survey focused on exploring the occupants’ behaviour characteristics and their indoor air quality perception with their comfort. Chiang Mai, Thailand, was chosen as a case study. Chiang Mai is the fifth largest city in Thailand, with a metropolitan density of around 2,400 people per square kilometre, and also considered a tropical savanna climate (Aw). The participants have recruited adults, with the only criteria being that they live in multi-storey residential buildings in Chiang Mai. Multiple-choice questions and Likert scale were used in the electronic questionnaire as a measurement method. 482 completed surveys were obtained and analysed via SPSS 27.0. In analysing statistics, the Cronbach’s alpha, Spearman’s rank and Pearson correlation coefficient, and stepwise Multiple regression analysis were applied to identify the main factors of human behaviour in household and indoor air quality perception on occupants’ comfort. The result showed that human behaviour characteristics in the room, such as washing clothes, cooking, and hanging clothes for drying, strongly correlate with indoor air quality perception. For instance, washing characteristic has a solidly negative correlation with the mould level in the room, which means mould could occur more if they wash clothes in rooms. In general, the overall occupants’ comfort has a significant relationship with indoor quality scales, including temperature, ventilation, humidity, and mould level. Natural lighting and air freshness level are the most influences on occupants’ humidity comfort. The five critical factors of overall comfort satisfaction are the environmental satisfaction of natural lighting, humidity, temperature ventilation and room privacy. In such vital factors, temperature satisfaction is the primary factor of the overall comfort, followed by natural lighting and ventilation, respectively. The results of this study may assist architects, buildings’ constructors, and engineers in generating improvement of indoor air quality of their design projects for their occupants achieving indoor comfort