Foto: Christian Alsing
How is reliance on artificial lighting affecting us?
- Artificial light, such as electric light, is degrading our psychological health.
- LEDs, used in many places as a better alternative to electric lighting, emit high levels of “blue-rich white light,” which tells our bodies to ‘wake up.’ This disrupts our 24-hour internal rhythm, wearing on our physical health, alertness, memory and mood.
- In the long run, all of this can contribute to sleep disorders.
- It also puts us at a greater risk of sickness, obesity, diabetes and depression.
- Reliance on artificial light at night − for example, by night shift workers − has even been linked to higher instances of peptic ulcers and even certain kinds of cancer.
Conversely, better access to daylight has been linked to:
- Improved sense of vitality.
- Decreased daytime sleepiness.
- Reduced stress and anxiety.
- Shorter hospital stays − Studies in hospitals proved that better daylighting can lead to a 2-4 days shorter hospital stay for psychiatric and bipolar in-patients.¹
- A one-third reduction in the risk of poor sleep and mood disorders for every additional half-hour we get of daylight.²
The effect of daylight on performance
Since daylight has tremendous effects on our physical health, mental health and cognition, it’s no wonder that access to daylight dramatically affects performance − both academic and work. While it’s widely agreed upon that this is the case, an overwhelming number of offices and classrooms don’t provide adequate daylight.
When it comes to daylight in the workplace, for example, a study of seven office buildings in the Pacific Northwest³ shows that more than 83% of the occupants said they “very much” liked daylight and sunlight in their workspace, while only 20% felt they had a sufficient amount of it.
This is a problem because there are real performance implications associated with better daylight:
- In schools, it has been found that pupils with the most daylighting in their classrooms progress 20-25% faster on math and reading tests in one year than those with the least. According to the same study, having a large window area in one’s classroom can improve test results by the same proportion.⁴
- In offices, it has been shown that workers with ample views out of windows had a 6-12% higher work performance than those with no views.⁵ Another study found that daylight and the quality of views out of windows, taken together, explained 6.5% of the variation in employees’ sick leave.⁶
Designing better buildings to overcome these challenges
Through our lighting choices and the designs of our buildings, we can actively reclaim natural light and promote better health and increased performance in the buildings we create, and there is a real business case to be made for doing so.