Architecture

The "Diamond Lantern" of Beijing

Aluminium cladding creates striking geometric beauty rising into the sky.
8 May, 2017
Poly International Plaza is a new office tower in Beijing relying on the most cutting-edge construction materials, but drawing its design from Chinese history.
The tower is part of a new business district in the Wangjing area, halfway between the city and the international airport to the northeast.

Tower One is inspired by Chinese paper lanterns, so that the exterior is formed in a continuous diagrid pattern meant to shimmer like a jewel in the sun and sky. Locals call the 161-meter building by its "Diamond Lantern" nickname, celebrating a visual exterior that is achieved using white aluminium cladding on an exoskeleton.
That outer layer of panels works as part of the thermal envelope enclosing the offices in a building designed for optimal sustainability performance. The interior layer of angled glass give the building its lantern appearance, particularly after dark when lighting elements within the structure illuminate the exterior. In the daytime, the angles create visual connections between the office spaces and floors. The geometric layers of aluminium and glass reach to street level, where they are anchored in a plaza.

"The long-span structural design not only opens up the interior, creating a column-free work environment, but also employs a highly sustainable architectural (and) mechanical approach to address the climatic and air quality challenges particular to Beijing," say architects Skidmore, Owings & Merrill (SOM).
In addition to air quality, the design and materials were chosen for their performance in Beijing's extreme climate, and with consideration for the region's earthquake potential. Vents in the glass layer of the exterior open to air flow during the hot summers, while protecting against the harsh winters. According to SOM, the design for the 31-story tower lowers carbon emissions by 18 percent and energy use by 23 percent, and has won numerous awards for the innovation in engineering and construction.

Tower One is the center piece, built as one of three towers placed in an elliptical shape the architectural firm wanted to free from "the rigid geometry of the adjoining urban fabric, allowing the landscape of surrounding parks to continue seamlessly through the project site." In doing so, they also captured the sense of the Chinese lantern at the entrance door, offering welcome and bringing a sign of good luck.
The smaller buildings, each less than 84 meters high, are covered in far more subdued dark metal rods in a vertical grid. Those buildings – already sold by the client, China Poly Group – create the backdrop for the dramatic Diamond Lantern to rise above the pedestrian pathways and landscaping of the site. The building also needed to be consistent with the high-end aesthetics of the client, which is one of the nation's largest state-supervised business conglomerates with an extensive presence in real estate.

Inside the building, an atrium at the main entry is bathed in natural light as it sweeps up to the floors above. A second atrium serves the upper floors, and is reached by one of the building's main elevators. The top floor, built as a double-height crown enclosed in the same glass walls, is for vertical gardens.
"We went through a process of soul-searching with the client," said structural engineer Mark Sarkisian in an interview. "We looked at what the site means and developed something iconic and responsible."
Banner image: Morio/WikiMedia