Home Lighting

By Susan Bloom

Natural daylight can improve the health and well-being of inhabitants.

Although electric lighting has been both a privilege and a mainstay of modern culture for well over a century, more and more studies have proven that the presence of natural daylight can positively impact one’s mood, health, behavior, satisfaction and productivity.

Consider these results from recent studies commissioned by the Heschong Mahone Group, a California-based firm that specializes in the field of building energy efficiency, in conjunction with Pacific Gas & Energy:

• In a 2003 study of 100 call center workers at the Sacramento Municipal Utility District, the workers with access to daylight and a view through a window were found to process calls 6-12% faster, perform 10-25% better on tests of mental function and memory recall, and experience less fatigue and illness than workers who had no access to a window or view.
• A study of 73 retail locations in California—24 with a significant amount of daylight through skylights—found that those stores with greater use of daylighting experienced an up to 40% increase in sales compared to stores with less or no daylighting.
• In California’s San Juan Capistrano school district, elementary school students who had the most access to large windowed areas and daylight progressed 20% faster on math tests and 26% on reading tests over the course of a year than did students with the least access. In similar studies in Seattle and Fort Collins, CO, students in classrooms with the most daylighting achieved academic scores that were 7-18% higher than students in rooms with the least amount of daylight.

According to David Hobstetter, a Principal at San Francisco-based KMD Architects, “Regular contact with daylight promotes circadian stimulation, regulating physical and mental function through our natural responses to the rhythms of light,” and helps to minimize the incidence of “cardiovascular problems, immune dysfunction, cognitive and functional deterioration and depression. Exposure to full-spectrum sunlight further enables us to synthesize vitamin D, which promotes strong nerve and muscle functioning as well as cell growth regulation.”

He adds: “Optimizing the use of daylight also has enormous potential to provide energy savings—electric lights can be turned off when sufficient daylight is available, cutting lighting and cooling costs dramatically.” For example, he shares, “The CEC estimated that incorporating skylights with automatic daylight sensors into all new educational buildings would save the state of California up to $7 million dollars in energy costs each year.”

Overall, Hobstetter concludes: “Windows that admit daylight and provide an ample and pleasant view can dramatically affect mental alertness, productivity and psychological well-being.”

So let the sun shine in and be sure to incorporate natural daylight into your lighting strategy to promote greater happiness, health, productivity and energy efficiency.

For more information about the beneficial effects of daylight, visit the Heschong Mahone Group at www.h-m-g.com or KMD Architects at www.kmdarchitects.com.

What You Need To Know About The Value Of Daylight

• Daylight offers psychological and physiological benefits to people
• Daylight also offers opportunities to save energy using automatic controls