It's not difficult to pinpoint which building along 15th Street Northwest in downtown Washington, D.C., is the Columbia Center. Completed in 2007, its glass curtain wall façade and glowing “lightbox” lobby stand out amid the surrounding drab 1970s precast concrete office buildings—which is exactly what the architect and client wanted. “When Monument Reality, the developer, came to us, they said, ‘We want you to design a building that is not your typical D.C. box,'” explains Michael Hickok, principal of D.C.-based Hickok Cole Architects, the firm that worked on the project. “‘We want you to design a building that will transform this block.'” And transform it has, especially by creating a nighttime presence with light radiating from the lobby onto this downtown street just blocks from the White House.
Hickok Cole Architects took the reins on the project and ran an in-house design competition over several weeks to come up with the final design concept. “We like being able to draw on the talent of a lot of people in the firm,” Hickok says. With the building having such a large footprint at 415,000 square feet, he notes that the greatest design challenge was how to bring people through the entry sequence from the building perimeter at 15th Street into the lobby and back toward the elevator core. Also, despite the building being on a mid-block site, it receives natural light on all four sides because of adjacent public alleyways. “If we put the lobby in the center of the façade, you'd be left with slender retail spaces on either side, and you'd be challenged to take people 200 feet deep into the site without any natural light,” Hickok points out. As a result, the architects moved the entry lobby to the southeast corner of the site, and that is where the idea of a lightbox was developed.
Knowing the lobby had to be of a certain scale to be seen from blocks away, the idea of a “three-story glass cube” emerged, Hickok says. While the design team was happy with this solution, it did have to address the fact that one long face of the entry overlooks the alley adjacent to the Columbia Center's neighbor, the Washington Post. “It's not the greatest view; the wall is blank and you can look back and see their loading dock,” Hickok notes. “We were contemplating some way of screening that a little bit from the lobby without blocking light.” Numerous options were discussed, including talk of using trees either outside or inside the lobby. Installing an interior bamboo garden was suggested, but the architects were not sure about using the real plant. Eventually, the idea for light rods shaped like bamboo emerged. “It would be sculptural and abstract but do the same thing the actual bamboo would do,” Hickok says. “It would provide immediate scale while also serving as a screen.”
It took the team from Chevy Chase, Md.–based Claude R. Engle Lighting Consultant about seven mock-ups to find the right plastic for the custom-made artificial bamboo rods, says firm vice president John Wood. “We had the manufacturer paint the top of the plastic white, so it bounces the light back down the tube when the light gets to the top.” The 2-inch-diameter rods ranged in length from 8 feet to 14 feet depending on their orientation, and are placed randomly in small groups of two or three along the east side of the lobby. Illuminated with a fiber optic projector using 150W metal halide lamps, it was necessary to cut through the slab and surface-mount the illuminators on the garage ceiling below. One fiber optic illuminator can light five bamboo rods, which are one brightness and not dimmable.
To support the overall structure, a large building column typically would have had to be located in the southeast corner, where the lobby is housed. Rather than installing a large, obtrusive column, the architects played off the bamboo idea of the light rods and broke it up into several smaller columns. “Some of them are angled off each other and spread out a little bit so they're really more akin visually to the bamboo than they are to a structural column,” Hickok notes.
The main feature in the lobby is the three-story dichroic glass wall, which originated from the idea of creating an “abstract waterfall,” Hickok explains. The dichroic glass panels, in 3-foot-6-inch by 1-foot strips, are located between laminated blue glass and are illuminated from top and bottom with quartz 250W PAR38 lamps (three per panel) that are mounted flush in the floor and on a surface-mounted track in a cove at the ceiling line. The dichroic glass panels, which Hickok says “catch the light from different angles beautifully,” do not run up the wall continuously and expose the wood surface behind them.
There is not much downlighting used throughout the lobby, which is possible because of the large amount of natural light received during the day and the glow of the electric light at night. Walking through the lobby toward the elevators, perimeter walls are illuminated with lensed wallwashers using PAR lamps. Fluorescent covelights with T8 lamps illuminate the elevator cab area. Wood says there is a lot of wattage used throughout, but it is all managed with a lighting control system set to four scenes: daylight, dusk, night image, and night security. Because of the abundance of natural light in the space, much of the electric lighting is off during the day.
“We didn't want the lightbox to be an ice cube kind of space,” Hickok says. “We wanted it to be a warm, inviting space.” This was achieved by the materials selected to complement the lighting: wood paneling and light-colored floor stone in an effort to bounce around as much natural and electric light as possible to illuminate the lobby. Day or night, the lightbox fulfills its goal by setting the Columbia Center apart from the rest of the buildings on 15th Street in the nation's capital, using light to attract attention to the three-story glass lobby and the building itself.
Project Columbia Center Lobby, Washington, D.C.
Client Monument Realty, Washington, D.C.
Architect Hickok Cole Architects, Washington, D.C.
Lighting Designer Claude R. Engle Lighting, Chevy Chase, Md.
Project Size 415,000 square feet (building); 4,200 square feet (lobby)
Photographer Prakash Patel, Washington, D.C.
Manufacturers / Applications
Fluorescent covelight fixtures in the elevator core
Low-voltage flush uplights with remote transformer
Incandescent wall-washers and downlights in lobby
Custom bamboo rods
Incandescent uplights to illuminate the dichroic glass wall