61 Flavors of Daylight
| Authors: | Mudit Saxena, Lisa Heschong, Heschong Mahone Group, Inc.; Kevin Van Den Wymelenberg, Univerisity of Idaho Integrated Design Lab - Boise; Seth Wayland, Innovative Power Analytics |
| Published: | August 2010 |
| Links: | Pre-print pdf | Online publication |
| Abstract: | A field study collected data on a range of 61 daylit spaces in six cities with a range of climate types around the United States. Occupants were surveyed about their visual comfort, and a team of daylighting experts visited each space to evaluate perceived daylighting quality. Annual simulations of each space were performed using a new annual simulation approach based on RADIANCE that produced a variety of metrics to describe the illuminance levels and daylighting characteristics of the spaces. The research team developed new reporting and visualization formats to better understand the analysis of complex annual simulation data across a large sample of spaces. These data were analyzed in conjunction with expert and occupant qualitative assessments to determine which metrics and specific criteria best explained the variability in subjective responses to a suite of daylight sufficiency and quality categories. This paper reports on the annual simulation visualization methods innovated and applied across all study spaces, focusing primarily on the daylight sufficiency metric. Findings from the annual illumination analysis are presented for all 61 spaces, with an emphasis on their ability to distinguish between alternative designs. Assumptions about the operation of window blinds proved to be a key variable in predicting annual illumination levels in the simulations. Differences in simulated illumination data are highlighted for three extremes of blinds operation—all open, operated and all closed—revealing the risks and resilience of different designs. A new method of ranking space designs by annual daylighting performance is discussed. Preliminary regression analysis of occupant and expert assessments and annual daylight illuminance calculations from simulation data are discussed. |