Tuned Up

We’ve all been there: You walk into a brightly lit store at night, and the intensity hurts your eyes. The culprit is cool-color-temperature lighting – light that more closely mimics daytime hours. Though static illumination was once the only option, recent advancements in LEDs and tunable white lighting have offered new solutions. 

Without getting too much into the nitty-gritty, tunable white lighting products allow end-users to adjust the source’s color temperature from a warm 2000 kelvin (or below) to a cool 6000 kelvin (or above), depending on the manufacturer. In layman’s terms, the user can “tune” the amount of white light in a space to their liking.

Despite the thinking that sources should possess accurate color-rendering indexes (CRI) so customers don’t feel misled (e.g., a dress shouldn’t look drastically different in natural daylight versus in-store), retailers can use tunable white light to highlight products or special areas, create contrast or complement the light levels outside so certain intensities – like bright lights at night – aren’t jarring to shoppers.

Tunable white light can also be used to support circadian rhythms, our biological “clocks” that control the release of hormones triggering sleep-wake cycles.

“The circadian cycle causes a fluctuation in the body’s production of various hormones from the hypothalamus and the pituitary, pineal, adrenal and thyroid glands,” explains Joan Roberts, Ph.D., professor of chemistry, department of natural sciences, Fordham University (New York). “If artificial lighting does not follow this natural spectrum of sunlight in the morning and darkness at night, the result can lead to depression, metabolic disorders like Type 2 diabetes and a lack of immune protection.”

Some healthcare facilities and offices utilize astronomical time clocks, which gradually and automatically adjust the color temperature of a source to coincide with the rising and setting of the sun. This aids in combating ailments like intensive care unit psychosis, and in offices, it increases worker productivity and prevents eye fatigue.

So what about retail? “In order to adjust your melatonin (hormone) levels and your circadian response, you have to be exposed for at least 20 minutes,” says Nelson Jenkins, owner, Lumen Architecture (New York). “It depends on the shopping experience, but I don’t believe most shoppers would come in and stay for more than 20 minutes.”

That doesn’t mean stores can’t use lighting to support circadian rhythms, but it would have little to no effect with short exposure.

TRADING SPACES
Always looking at ways to strengthen the personal connection between a shopper and a brand, many retailers are creating mixed-use areas in their stores. Whether these function as spaces to host after-hours parties or to promote campaigns, lighting helps set the stage.

“Retailers are often selling a lifestyle as much as they’re selling any product,” says Jenkins. “[Our firm worked on] a swimsuit showroom and installed tunable white lights. In the evenings, you can set it on a warm temperature for parties, but it doesn’t show off the product as well.”

And that’s a key point: It’s important for guests to feel that they’re at a special event and not shopping.

“A client of mine had a cocktail hour at one of their stores after-hours,” explains Kathryn Toth, senior designer, Lighting Design Alliance (Long Beach, Calif.). “The store was lit with metal halides, so there was no mood lighting to be had. It was like being in a store shopping, not at a party. That whole environment changes if you have a chance to dim.”

Jules Gim, CallisonRTKL’s (Baltimore) New York-based lighting designer, says theatrical lighting is sometimes required, depending on the application, but if they’re not appropriate for the space, implementing a dimming system with set scenes can also create a dramatic change. “All of a sudden it becomes this dark, moody performance space at night, but during the day, it’s a beautifully lit retail environment,” she says.

DIM IT DOWN
As most lighting designers know, Title 24 of the California Energy Commission requires light to be dimming-capable in California. While the rest of the U.S. plays catch-up, advancements in LED drivers continue to be important.

“The LED has to speak the same language as the dimmer. If it doesn’t, that’s a problem,” says Toth. The problem manifests itself as strobing or flickering LEDs and lights randomly popping on and off.

And whenever you dim, you want it to be unnoticeable. “Say you’re in a restaurant, and they dim the lights because it’s dinnertime, but they don’t dim them slowly enough, and you notice,” explains Toth. “You automatically look up from whatever you’re doing, whoever you’re talking to, and wonder, ‘What time is it?’ ”

LIGHTING 101
Overall, designers need to keep it simple. Gim and Toth both recommend preset systems since controls are complicated and employee turnover can cause a lack of knowledge in system operations.

When lighting designers are discussing in-store applications, Professor Roberts says, “Reach them with simple English. Talk to the retailer not about the light source but about the customer. Not kelvin, not watts – it’s all about happy customers.”  

Kid’s Cavern in Macau, China, showcases the trend of integrating light into architecture. 40,000 LEDs embedded into the store’s façade change color and shift through various patterns, creating intrigue for passersby. Video: Courtesy of CallisonRTKL.

WHAT’S HOT
Several other trends are continuing to grow in popularity, including architectural integration:

“As LEDs become smaller and more compact, and their outputs become brighter, it’s easier to integrate those sources into architectural details, like behind backlighting surfaces or cove cavities,” explains Nelson Jenkins, Lumen Architecture (New York).

“You’re also seeing LEDs integrated into translucent materials; say an animated and dynamic screen you can program, but when you press a button, it transforms back into a clear piece of glass,” says Jules Gim, CallisonRTKL (Baltimore).

Others include daylighting in restaurants: “People aren’t looking to go into a dark bar in the middle of the day,” says Jenkins. “But in the evenings, you want a romantic, candlelit environment.” This is accomplished by using a cooler color temperature during the day, in conjunction with daylighting, and reducing the light level in the evening.

Jenkins explains some recent studies also proved stores that use daylighting increased employee retention and happiness, specifically in high-bay stores like Costco and Home Depot.