The influence of sky conditions and glass on the human thermal perception in a bioclimatic chamber

Abstract

The study evaluated the influence of sky conditions on the thermal perception of occupants, considering diverse types of glass, and observing the possible interference of the time of exposure and visual contact with the outdoors. To this end, forty-eight volunteers were exposed to three types of glass (clear and two solar control) in a walk-in climatic chamber, under clear, partly cloudy, and overcast sky conditions, during the morning and afternoon, with and without visual contact with the outdoors. Environmental and physiological thermal variables were measured, and thermal perception questionnaires were administered, which were later compared to the calculated PMV. The results were analyzed statistically. It was found that the thermal evaluations of the occupants are related to the type of sky, but independent of the type of glass or the interaction between the two. It was also observed that thermal perception is related to the time of day, as well as the interaction between this and the type of sky. Finally, the visual contact with the outside affected how atmospheric conditions influenced the thermal perception volunteers’ vote. It was concluded that atmospheric conditions influenced the participants' thermal perception, regardless of the type of glass, and that the time of day and visual contact with the outdoors may interfere with how these conditions influence the thermal votes, but in diverse ways. Therefore, the climate control and layout of environments can take these aspects into account for optimization, both in offering comfort to users and for the rational use of energy.