Effect of Indoor Temperature and Glazing with Saturated Color on Visual Perception of Daylight

This paper presents the combined effect of indoor temperature (19 degrees C, 22 degrees C, and 26 degrees C) and colored glazing (blue, orange, and neutral) on visual perception of daylight. Experiments were performed in an office-like test room, in which 75 participants were fully immersed under visual and thermal stimuli. Findings are discussed in terms of cross-modal effects of indoor temperature on visual perception, as well as of unimodal effects of glazing color on visual perception, investigated in terms of color of light and visual environment evaluations. Results show the presence of cross-modal effects of indoor temperature on visual perception of both the visual environment and the color of light. Indoor temperature affected the visual environment evaluation as, first, brightness comfort resulted higher at lower temperatures, and second, the light was associated to warmth adjectives more often at higher temperatures. On the other hand, indoor temperature influenced the color of light evaluation as, only at lower temperatures, daylight tinted by the blue glazing was considered less pleasant and less comfortable, and was chosen less often over the daylight tinted by the orange glazing. In terms of unimodal effect of colored glazing on visual perception, results indicate that the neutral glazing was always preferred over the two colored ones, probably due to the use of saturated colors. The orange glazing, however, was associated with the most relaxing and warmest daylight. These findings have important implications regarding the use of glazing with saturated colors in buildings and expand our understanding of temperature-color interaction - so far investigated only with electric light - to daylight evaluations.