Occupant’s Perception and Preference of Thermal Environment in Free-running Buildings in China

Abstract

The purpose of this paper was to present the occupants’ perception and preferences of thermal environments in free-running buildings in China. A study of the thermal environments in eight university dormitory buildings was conducted from September 2008 to July 2009 in Chongqing, China. A total of 1829 returned questionnaires were collected. Indoor and outdoor air temperatures, relative humidity and air velocities were measured while the questionnaire surveys were conducted. The scores were given based on the subjective scales used for the study on the students’ indoor thermal perception and preferences. The accepted temperature range was 15.9—28.2°C. The preferred temperature was about 23.2°C. The neutral temperature was 22.1° C. A higher tolerance of temperature was shown by the occupants in this sub-tropical climatic region of China. The relationship between thermal preference and actual thermal sensation in different seasons was also analysed. People’s air movement sensation was related to their thermal sensation. The majority of subjects (53%) were satisfied with their indoor air humidity when the thermal sensation was neutral. The relationship between humidity sensation and preferences showed that the effect of humidity on thermal comfort should not be ignored at high and low temperatures. Student dormitory buildings were used in this study to provide comparatively worse case information on occupants’ thermal comfort characteristics in residential buildings in China.

A review of human thermal comfort in the built environment

“…Results indicated that the HVAC systems generated a comfort expectation for users, adjusting the comfort zone to warmer in winter and cooler in summer [308]. A research project conducted in naturally ventilated university dormitories in China demonstrated that user have a higher tolerance of temperature and that the effect of humidity on thermal comfort at high and low temperatures should not be ignored [309]. Sekhar and…”

Investigation of students’ comfort and adaptation in university dormitories in humid subtropical climatic area in winter in Chongqing, China

“…Figure 1 shows the interior space of both Chinese and International student rooms. As noted by Li et al (2010) general residential buildings compared to dormitory buildings are characteristically small with a high occupant density but without heating ventilation and air-conditioning (HVAC), indicating that the indoor thermal environment in dormitory buildings would be generally worse than normal residential buildings in China, especially in winter or summer season. In our study this can present a different scenario in winter.…”

“…For example, in typical university dormitory buildings in Harbin, China, a severe cold region (Ning et al, 2016), Beijing campus buildings (Cao et al, 2014), naturally ventilated (NV) buildings in a hot-humid area (Y. Zhang et al, 2010), hot-humid climate in summer in dormitories of a university (He et al, 2016), severe cold winter and hot summer in university dormitories (Li et al, 2010) and humid areas (Cheng et al, 2008) .…”

“…To create a more comfortable indoor environment in this kind of environments, it is necessary to carry out further studies on comfort levels for multi-occupant spaces, especially students' dormitory rooms. In university dormitories, thermal comfort does not only affect students' comfort and health, but also their learning needs and the quality of their lives (Li et al, 2010). Educational institutions own many buildings, thus resulting in significant demand for comfortable environments to increase occupants' productivity.…”

“…It has cloudy and foggy weather; the annual mean number of foggy days is 104 (Ding et al, 2012). Li et al (2010) presented the occupants' perception and preferences of thermal environments in free-running university dormitory buildings in China. The authors reported that the acceptable temperatures in university dormitories in Chongqing were between 15.9°C and 28.2°C and the preferred indoor air temperature was 23.2°C, and a higher tolerance of temperature by the occupants in the sub-tropical climatic region of China.…”