The Case for Occupant-Centric Daylight Analytics: a Comparison of Horizontal Illumination and Immersive View

Daylight is valued as an energy efficient alternative to electric light and over the past few decades, climate-based horizontal illuminance metrics have demonstrated the importance of variable sky conditions on annual predictions. These metrics allow us to evaluate a building as an ensemble of spaces that can achieve a pre-set performance target. In addition to daylight's ability to offset electric lighting, it can also impact psychological and physiological responses in building occupants, such as discomfort from glare, alertness, mood or sleep quality through non-visual effects, and emotion from perceived contrast and composition, all of which depend on a specific field-of-view. Occupant-centric or 'view-based' models pertaining to daylight indoors can provide complementary point-in-time or aggregated predictions of an occupant's response over time, but are difficult to compare to horizontal illuminance or 'task-based' metrics in a simulation environment, because the sensor position, view direction, and time granularity vary greatly between each approach. This paper uses a simulated office floor plate with varied seating and wall configurations to propose a method of scoring task-based and view-based metrics, allowing for a relative comparison. The results of this comparison reveal a disconnect in performance narratives between each approach, supporting the need for further work to develop an integrated approach for comparing building and occupant-scale performance considerations.