The sky's the limit with laminated glass

It is designed by architects Cesar Pelli of New York and Leo A. Daly Pacific Ltd. of Hong Kong. The building's façade uses 40,000 m2 of laminated glass with DuPont™ Butacite® PVB for noise attenuation and typhoon resistance.

Bob Randall of global glass fabricator Viracon said: "The Queen's Road Central, where this high rise is located (leading to the project's abbreviated name, 2QRC) is one of Hong Kong's busiest streets. The architects asked us to provide a space that was acoustically and thermally comfortable for the occupants. Since laminated glass with Butacite® provides excellent sound attenuation, we laminated the entire façade of the building using DuPont's PVB interlayer.

"The high wind loading conditions of this geographic location were another reason for the choice of laminated glass with Butacite R, because of the added strength and resistance to glass fallout that the material brings. So well-known are the benefits of laminated glass in typhoons that we believe the Building Department of Hong Kong is, at this time, rewriting the building codes to include a more comprehensive specification of laminated glass in the city.

"With the Cheung Kong Center, our aim was to provide a glass façade that is as flat, distortion-free and reflective as possible. It starts with a 10 mm clear, heat-strengthened glass pane, followed by a Viracon stainless steel coating giving a silver reflective appearance. This is followed by 1.52 mm Butacite® PVB, and 6 mm clear heat strengthened glass on the inner lite – a total thickness of 17.52 mm."

Randall reported that following a major typhoon in 1999 "less than 10 pieces of glass had to be replaced at 2QRC – a major achievement, since many buildings around it suffered heavy damage." Faced with such violent weather extremes, standard or tempered glass would have fallen out of the frame, potentially harming people on the street below and leading to extensive damage to the interior of the building. The glazier for this project was Permasteelisa (HK) Ltd. and the developer was Cheung Kong Holdings Ltd.

'Pizzaz' for The Center (H6), Hong Kong

The Center, in the Sheung Wan area of Hong Kong (completion: 1997) was designed by Dennis Lau and Ng Chun Man Architects & Engineers (HK) Ltd. At 70 stories (345 m) high, it is one of Hong Kong's tallest buildings.

Viracon's Bob Randall explained: "Like the Cheung Kong Center, The Center (H6) features very lovely lighting on the curtain wall which, in this case, is made of 46,000 m2 of laminated glass with Butacite® PVB. As in the case of the Cheung Kong Center, laminated glass was selected for its noise attenuation and typhoon-resistant properties."

The glass configuration in the vision area of the façade is similar to the Cheung Kong Center. However, the spandrel area of the laminated glass contains a Viracon Silkscreen fritted silkscreen pattern. Randall commented: "The architect wanted to introduce a decorative element to differentiate H6 from the surrounding glass facades. For this reason, H6's façade also features attractive, interactive neon lighting on its curtain wall at night that switches from red to yellow to green to blue. It's a building with a lot of pizzaz!"

Lansheng Mansion, Shanghai

When Chinese developer Shanghai Lansheng Group commissioned a new corporate headquarters in downtown Shanghai, architects Zhejian Architectural Design Institute designed a stunning, gold laminated glass façade for the building, called the Lansheng Mansion (completion: 1997). The project incorporates 8,000 m2 of laminated glass with Butacite R PVB in the façade, used to protect the gold coating and to enhance safety – specifically in preventing glass fallout.

Laminator Shanghai Yaohua Pilkington Glass Co. Ltd. made a construction of 6 mm coated LOF glass + 0.76 mm clear Butacite R PVB + 6 mm Line Vapour Chemical (LVC) glass, which was installed by glazier Shanghai Jian Qiao Rui He Decorative Glass Co. Ltd.