Abstract
The purposes of this study were to investigate the actual state of the indoor thermal and air environment in general apartment houses during winter in Cheongju City, to analyze the related factors with the indoor thermal and air environment, and to make suggestions for the improvement. A series of visiting field investigation was conducted in twenty units between 28th December, 2010, and 11th March, 2011. The field investigations included the measurement of physical indoor environmental conditions, the observation of architectural characteristics and resident's behavior, and the on-site questionnaire survey of residents. The measured values of each units were compared to evaluation standard and were categorized to group by the difference between units. Factors related to the difference of the measured values between the groups were analyzed. The findings are summarized as followed. The indoor temperature of apartment houses during winter in Cheongju City was generally suitable. The relative humidity was slightly dry, while the $CO_2$ concentration was found to be excessively high. The factors related indoor environment were analysed as heating operation, ventilation, gas range use, and hanging out the wash to dry in indoors.
