Hong Kong’s Xiqu Centre, a subtly curving, eight-story structure with a not-so-subtle textural façade, puts the concept of a curtain back into curtainwall. Designed by Revery Architecture (formerly Bing Thom Architects), which has offices in Hong Kong and Vancouver, British Columbia, with local firm Ronald Lu & Partners, the 320,000-square-foot performing arts venue features more than 13,000 extruded aluminum fins on a unitized-panel façade. The effect is large in scale, a building draped in a metallic stage curtain, drawn strategically to reveal corner entrances and a handful of window-like openings that support natural ventilation.
Xiqu is Mandarin for Chinese opera, and the center is one of the first contemporary structures purpose-built for the art form, housing the 1,073-seat Grand Theatre; the 200-seat Tea House Theatre; rehearsal, administrative, dining, and retail space; and a 21,000-square-foot open-air atrium accessible by the public. Xiqu is the first of 15 planned cultural venues slated to open in Hong Kong’s West Kowloon Cultural District, a 40-hectare development being built on land that once was Victoria Harbor.
For its façade, the team took inspiration not only from stage curtains, but from the dramatic costumes worn by xiqu performers and the Chinese concept of qi, or flow, which can be expressed in everything from calligraphy to martial arts. The result is a rippling façade whose drapes and folds seem to hang from the roof. Heightening the illusion, portions of the façade appear to overlap with one another, like adjacent curtain panels.
To make the façade cost-effective, Revery used 3D modeling software to optimize the fin geometry. Each fin is CNC-cut from a curved piece of extruded aluminum to produce two identical wave-like blades. Despite the façade’s overall multidimensional effect, nearly every asymmetrical blade is identical, with the exceptions bordering curtain openings in the. Measuring 7.9 feet long, 12 inches wide, and 6 to 14 inches deep each, the fins are arranged end-to-end in an alternating fashion—top to bottom, bottom to top—to create sinuous curves that undulate across the theater surface. Each vertical array of fins never tilts or changes orientation.
The fins are bolted to 3-millimeter-thick aluminum panels, approximately 18 feet by 7.5 feet, that make up a unitized curtainwall system anchored to the building’s concrete-and-steel structure. Unlike the fins, each aluminum panel is unique and coded by the BIM model for identification and installation.
The connections between the fins and the vertical panels were among the most challenging to develop, says Revery design principal Venelin Kokalov, who took over the firm following the 2016 death of its namesake, the Hong Kong–born Canadian architect Bing Thom. Where possible, the architects wanted to minimize and conceal the connections, which also had to be strong enough to withstand Hong Kong’s infamous typhoons.
The architects explored options using 3D-printed prototypes at Revery’s Vancouver office, and then built a full-scale, aluminum mock-up in Hong Kong. The final connection detail involves a custom stainless steel bracket that slides into a groove cut into the back of each fin blade. The bracket is secured to an aluminum transom by an M30 bolt and to the fin with two capped M10 screws. Each fin is secured in three places—top, bottom, and center—to the aluminum panel via the transom.
Revery used the mock-up to test how the aluminum would weather. The marine-grade, corrosion-resistant alloy was left uncoated and bead-blasted to create a rougher texture. “We wanted this natural look of the aluminum, not to be polished,” Kokalov says. “We wanted the material to transform with time.” The façade panels were prefabricated in Guangdong, China, and arrived at the building site pre-numbered to streamline installation, which required eight months. Attaching the 13,000-plus fins took another eight months.
For Kokalov, the Xiqu Centre was a deeply personal project, marking his final collaboration with Thom, a friend and mentor. Its completion in January was a reminder of the firm's tireless efforts. “Fight,” he says. “Fight every day. To save an idea, you have to work hard. Otherwise, people take the safe route and the easy path. For us, it was important to not give up.”