Abstract: People living in developed countries conduct the majority of their daily lives indoors. With the ultimate goal to improve building design and operation and guarantee occupant comfort and well-being, increasing efforts are devoted to understanding how people perceive the indoor environment. Past studies have focused on the four factors considered to have the biggest influence on the quality of the indoor space: visual appearance, thermal condition, acoustic ambience, and air quality. In particular, the effect of one factor at a time has been investigated, resulting in comfort models (e.g., thermal comfort), standards, guidelines and quantitative indices, which provide threshold values for light, temperature, noise, and air quality separately. As a result, buildings and technologies devoted to control the indoor environment are designed on supposedly independent effects of visual, thermal.and other factors. Nevertheless, people are simultaneously exposed to multiple indoor stimuli, and their perception of the indoor environment cannot be dissociated from the combination and interaction of these stimuli.

This presentation focuses on the effect of visual and thermal factor interactions on human comfort in buildings. Based on the first worldwide available experiments conducted in an office-like test room, with more than 200 participants, results show that visual and thermal factors interact influencing human perception. In particular, indoor temperature affects how people perceive the visual environment, and light (specifically, daylight transmitted throughout colored glazing or at different intensities) influences building occupants’ thermal perception. Results were primarily psychological rather than physiological. They occurred under indoor factors normally found in buildings or that can be related to the use of specific façade technologies such as new glazing materials or transparent photovoltaics. As a consequence, these findings can be applied to building design and operation or can be used to foster the development of control systems with the aim to achieve energy savings and increase occupant comfort and well-being.

Bio: Giorgia Chinazzo is a Ph.D. student in civil and environmental engineering at the Swiss Federal Institute of Technology in Lausanne (EPFL). She earned her B.Sc. and M.Sc. degrees in building engineering from the Politecnico di Torino. Her research interests and competences are centered on human comfort and perception, daylight, energy-efficient strategies, and sustainable design.