Indoor environmental quality (IEQ) acceptance of very small flat units of Hong Kong residents

Abstract

Hong Kong has a challenge of meeting the housing demand due to limited land supply. Recently, some very small residential units have surfaced to accommodate the population expansion in the city. As the extreme environmental conditions in these environment are insufferable to some people, indoor environmental quality (IEQ) responses of occupants living in these units may differ significantly from other field studies on IEQ acceptance in living environments. This study evaluates the IEQ with responses of 52 residents living in very small residential units. Individual acceptance towards IEQ parameters regarding the thermal, indoor air, visual and aural environment and overall IEQ are analyzed. In general, most of the IEQ parameters are comparable to data collected in average residential buildings. Regarding the thermal response, a narrower thermal acceptability range in this study shows a greater sensitivity to operative temperature change. A small variation in thermal acceptance indicates that the occupants have already developed tolerance to the hot indoor environment. While for indoor air quality, visual and aural aspects, acceptance variabilities are very small within the measurable range, suggesting that small unit occupants put less emphasis on these three aspects. The study also demonstrates that the overall IEQ acceptance in these units are less sensitive as compared with the average residential environment. Occupants are believed to have developed tolerance and adaptation to an unchangeable reality, which tiny changes of environmental conditions make no significant influence to their acceptances of individual IEQ aspects and overall IEQ.