Russ Leslie, associate director and professor at the Lighting Research Center at Rensselaer, along with Leora Radetsky, research scientist, and Aaron Smith, former research specialist, have been awarded the prestigious Leon Gaster Award from the Society of Light and Lighting for the paper, “Conceptual design metrics for daylighting,” published in Lighting Research & Technology last year. The award will be presented at the Society’s Annual General Meeting and Awards evening on May 28 at the London Irish Centre in London.
In the paper, Leslie, Radetsky, and Smith propose a new metric to help architects and builders more easily take advantage of the benefits of daylighting, from significant energy savings to the positive impact of light on health. This new metric—the daylighting dashboard—provides an early indication of a design’s potential to meet eight design goals that contribute to the successful use of daylighting. The dashboard metrics were developed through a project sponsored by the United States Green Building Council (USGBC).
The development of daylighting metrics has been the subject of considerable effort and debate, but no widely accepted metric has emerged to help recognize well-daylit buildings. Although simulation software exists to assist designers in daylight analysis, these programs are often overly complex and involve a high level of expertise. On the other hand, rule-of-thumb approaches that are often used to aid in the decision-making process are based on overly simplified assumptions.
Leslie and colleagues proposed the daylighting dashboard, a visual representation of a design’s potential to meet eight design goals: average illuminance, coverage, diffuse daylight, daylight autonomy, circadian stimulus, glazing area, view, and solar heat gain.
“We propose eight minimum components and a simple way to estimate performance at the very beginning of building design,” said Leslie. “The daylighting dashboard allows for flexibility in precision, calculation software, or bracketing values for the eight goals, which can be prioritized in the context of individual projects, rating systems, or code requirements.”
The daylighting dashboard is also the first integrative approach that includes a validated circadian stimulus model, taking into consideration the benefits of light on human health. An environment with healthy lighting, such as a space that is properly daylit, can encourage daytime alertness and more restful sleep at night.
This new metric provides an indication of performance and weaknesses of conceptual designs early in the design phase, while there is still an opportunity to make modifications. An architect facing one or more red flags during conceptual design could give further consideration to these issues or enlist appropriate daylight expertise. This early indication of performance of conceptual design alternatives is likely to guide architects toward better daylit buildings.
The Leon Gaster Award
The Leon Gaster Award is awarded annually by the Society of Light and Lighting for the best paper of the year, concerned with lighting applications, and recognizes the role that Leon Gaster made as the founder of the British Illuminating Engineering Society in 1909, which is the forerunner of the Society of Light and Lighting. The award was first made in 1929.
The image below exemplifies the use of the daylighting dashboard to compare three different classroom designs in their ability to meet eight design goals. Green (go) means the design is on track to perform well on that component, yellow (caution) means modifications may be warranted as the project develops, and red (stop) means the design is unlikely to perform well on that component.