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We spend a lot more time thinking about what colors to paint the walls of the rooms that we live in than we do choosing the colors of the light bulbs we use to light those spaces. And that is unfortunate.
Light comes in distinct colors, and selecting the right one to use in a space helps to make it more likely that what we want to happen in a particular place will indeed occur.
Here, we won’t discuss how we respond to being in spaces lit by those garishly colored red and green and other bulbs sold around Halloween and other holidays. We’ll be reviewing the implications of being in spaces lit by slightly warmer light or somewhat cooler light. The warmer light we’re concerned with ranges from around 2700 degrees Kelvin to around 4000 degrees Kelvin, which is where more clearly cooler light begins. Noticeably cool light is found at around 6500 degrees Kelvin, or so. To use the scientific research on light color in your life, you don’t need to search out the degrees Kelvin of a bulb you may be considering buying, it’s enough to focus on whether a bulb is labeled “warm” or “cool.”
Being in cool colored light is great if we’re doing mental work; better cognitive performance has been linked to being in places lit with cooler lights. The lights in your office, home or otherwise, should be cool. If your home office multi-tasks, try to make sure there’s a lamp on your desk stocked with a cool bulb that you can turn on while you work. You want to be sitting in cooler light when you’re trying to concentrate. Cooler light can keep us awake, one of the reasons it's good to stop using electronic devices (which emit blue-ish light), such as iPads, long before bedtime.
Being in warm light has been tied to very different consequences. We seem to feel more relaxed under warm light than cool and to get along better with others when we’re in a warmer glow—so there’s a good reason to light a fire in the fireplace before a potentially contentious family gathering—or at least start burning a few candles. The glow from a fireplace or candles also creates a “together” zone in a larger room, a sort of room within a room. Research also indicates that we think more creatively under warmer light.
Light of different colors can help calm us, or enhance our cognitive performance, or make it more likely that we’ll get along with others, and even think creatively. Light bulbs can’t guarantee that we’ll be calm, etc. Nothing can. Like other sensory, social, cultural, etc., factors, bulbs of different colors do, though, make some outcomes more likely than others.
Design informed by science is bright design, and that never goes out of style.
