Evaluating thermal comfort and neutral temperature in residential apartments in hot and dry climate: A case study in Shiraz, Iran

Determination of thermal comfort, as one of the main goals of climate design, is of great importance due to its direct impact on human productivity and health, the interior space quality, and the energy consumption reduction, regarding the fact that most of the human activities take place in the house. Though providing crucial design information, determination and analysis of the thermal comfort range is a challenging issue due to variety of climatic, physiological, and cultural influencing factors, which in turn, necessitate field studies. Considering the critical need of determining thermal comfort range for each climate, this research aimed to describe field study of thermal comfort conducted in mid-rise residential apartments with open courtyards in hot and dry climate of Shiraz, Iran to provide neutral temperature, thermal comfort range, and the relationship between neutral temperature and indoor as well as outdoor temperature. The data and information needed, based on the experimental and field methods, were collected using the two main methods of questionnaire and measurement and the results were discussed with analytical and inferential description. In addition to a positive correlation between indoor air temperature and PMV as well as AMV, the findings of survey and regression analysis reveals a good relationship between neutral temperature and indoor temperature and also, between indoor comfort and outdoor conditions. Furthermore, a neutral temperature of 27.18 °C and the comfort band (23.2–30.8 °C) vindicated that respondents achieve comfort at a higher indoor air temperatures compared with the recommendations of international standards such as ISO7730. Moreover, the regression equation between the preferred and neutral temperature suggests that the neutral temperature can be used as a suitable criterion for predicting indoor temperature. •The summer comfort temperature was found to be higher than international standards.•A positive correlation between indoor temperature and Actual Mean Vote was found.•The findings reveals a good relationship between neutral and indoor temperature.•A good relationship between indoor comfort and outdoor conditions was detected.•Neutral temperature can be a suitable criterion for predicting indoor temperature.