The Relationship between Sunlight Pattern Geometry and Visual Comfort in Daylit Offices

  • Belal Abboushi University of Oregon
  • Ihab Elzeyadi University of Oregon


Sunlight in buildings is a multisensory phenomenon that can enhance occupants’ comfort, health, and connection with the outside environment through its dynamic luminous and thermal attributes. Current daylighting design guidelines limit sunlight penetration in work environments, reducing both its negative and positive effects on visual comfort and occupants’ satisfaction with their indoor environment. One gap in existing literature on sunlight exposure is the lack of addressing the effect of visual interest for both sunlight pattern geometry and its play of brilliants on visual comfort. This paper aims to examine differences in visual comfort and interest assessments under three different sunlight pattern geometries. This paper reports on the results of a quasi-experiment conducted in an office building in Portland, OR. Three experimental settings (hereafter test stations) were created at the office using different window treatments to create three sunlight geometries −Fractal Pattern, Striped Pattern, and ‘No-Pattern’− which were tested and compared for their impact on visual interest, visual comfort, and view quality. The study followed a withinsubjects design (same group experienced three different sunlight conditions) where 22 office employees completed a brief questionnaire at each test station, while quantitative environmental data were collected. Results showed that visual comfort and visual interest ratings for the Fractal Pattern were higher than those for the Striped Pattern, though the difference was not statistically significant. View ratings for the two patterns were significantly lower than those for No-Pattern (p<0.001). Interestingly, the relationship between the glare metric DGP and visual comfort ratings varied across the three stations. Further, the difference in visual interest between the Striped Pattern and No-Pattern stations was statistically significant (p<0.05). Overall, findings suggest that the visual interest of sunlight patterns and views influenced subjective visual comfort assessments. Implication of this study can inform the design of future facade systems to enhance occupants’ visual comfort, interest, and satisfaction with their indoor environment.

How to Cite
Abboushi, B., & Elzeyadi, I. (2018). The Relationship between Sunlight Pattern Geometry and Visual Comfort in Daylit Offices. ARCC Conference Repository.