Effects of Natural Ventilation on Occupants’ Positive Thermal Comfort in Office Environment

This study conducted a survey in a mid-season office to examine the effects of natural ventilation on indoor thermal conditions and occupants’ comfort. The survey was carried out in an office where occupants could choose between a naturally ventilated open area and a mechanically conditioned closed area. Environmental measurements, daily questionnaires and real-time comfort voting were analyzed. Natural ventilation increased thermal variability and shifted thermal sensation toward cooler conditions. The quality of comfort differed between ventilation conditions: momentary pleasantness contributed to satisfaction under natural ventilation, whereas avoiding dissatisfaction was important.