Many demands are placed upon new sports stadiums and arenas. Spectators expect state-of-the-art facilities for comfortable viewing in all weather conditions. Municipalities and other organisations making the large investment in these facilities are concerned about construction, maintenance, and utility costs, as well as durability and safety – particularly in view of recent extreme weather. And architects need materials that can enable bold new designs, such as sliding roofs and larger expanses, as well as beautiful surfaces. One way to meet all these requirements is to utilise high-performance engineering thermoplastics to construct stadium glazing systems. The popularity of plastics for construction glazing is driving development of new materials that can address virtually any challenge – from thermal control to self-cleaning to special tints and effects. Thermoplastics deliver a unique combination of advantages in roofing for large, complex structures like stadiums. Compared to traditional glass, plastic glazing is significantly lighter and highly impact-resistant for safety. It can be formed into complex shapes that are difficult to achieve with glass. These materials can be engineered with a variety of special coatings and tints for excellent weathering performance, enhanced light transmission, and easy maintenance. e proposition

Lexan Thermoclear sheet from GE Plastics is an impact-resistant, multi-wall polycarbonate (PC) glazing material. It features a proprietary surface treatment on one or both sides that provides excellent resistance against degradation from UV radiation, while transmitting visible light very well. It withstands high wind and snow loads and storms. The multi-wall construction of Lexan Thermoclear sheet also ensures excellent thermal insulation. It is available in X-structure and rectangular- structure configurations, and a variety of special coatings and finishes. This versatile glazing material has been used in arena roofing and other glazing for more than 25 years, beginning with a stadium in Split, Croatia, in 1979. It has also been used for several Olympic arenas, including Barcelona and Sydney facilities. And it was chosen for six stadiums that hosted the UEFA Euro 2004 Championship in Portugal. More than 74,0002 metres of double-sided, UVprotected sheet were used to create the roof glazing for these facilities. Currently, this industry landmark product is being used for the roofs of three stadiums being built for Euro 2008: Wankdorf stadium in Bern, Switzerland, and Klagenfurt and Salzburg stadiums in Austria. The Wankdorf facility will feature 4,0002 metres of Lexan Thermoclear SunXP sheet and the Austrian stadiums will be glazed with Lexan Thermoclear sheet – all will have two-sided UV protection.

Many sports stadiums, particularly Olympic arenas, are showpieces for their city or country. Therefore, the architects and designers seek to create new shapes and effects that will make the building iconic. The huge roofs of many arenas are envisioned with dramatic curves and sweeps of glazing. However, their sheer size makes light weight and stiffness essential. And their complicated shapes call for materials that can be formed easily. Compared to glass, Lexan Thermoclear sheet is significantly lighter in weight while offering high stiffness and more than 250 times the impact resistance. It can be easily cold-formed into many different shapes and configurations. For example, the Sydney Olympic Stadium in Australia – the largest roof using GE Plastics glazing to date – used 27,0002 metres of 16mm, 3-wall X-structure Lexan Thermoclear SunXP sheet. The material was chosen for the building’s most challenging engineering feature - the 300-meter span roof structure suspended from a huge arch. The roof is lightweight (the Lexan sheet weight is only 3kg/sq. meter) yet provides spectators with protection from the weather, while reducing wind resistance on the field. Modern design also implies a flexibility over colour as well as design, and plastic sheets come with an extensive range of colours and effects, whether that be to match in with current surroundings, or in the case of the Chongqing stadium in China, to utilise the special metallic visual effect of a grey sheet which also provides great solar reflecting properties.

To avoid high maintenance and replacement costs for glazing, many architects and builders select different Lexan sheet products for their resistance to yellowing, graffiti, scratching, and breakage. To help minimize maintenance costs, Lexan Thermoclear Easy Clean sheet products feature a patented hydrophobic coating that offers self-cleaning properties: when the material comes in contact with water, the coating reduces surface tension and increases the contact angle of the water on the sheet, causing the formation of large droplets that wash away dirt and leave a virtually spotless finish. Also, its lightweight, multi-wall X-structure configuration provides excellent stiffness and high impact strength. This GE product glazes the rooftops of several stadiums around the world, including Chongqing Stadium, which accommodates 60,000 spectators, and Celje Stadium in Maribor, Slovenia. Another prime concern for stadium maintenance and operation are heating and cooling costs. With industry solutions so advanced as to be able to offer can find a solution – which reduce heat build-up by blocking near-infrared radiation while allowing abundant natural light into the facility – with the Lexan Solar Control IR solid and multi-wall sheet grades. The ArenA in Amsterdam, whose 20,0002 metre sliding roof is glazed with Lexan Thermoclear polycarbonate sheet, also features one of the first commercial applications for Lexan Solar Control IR sheet. Its four escalators are enclosed in the material, which helps absorb infrared (IR) and near-IR radiation from the sun, potentially reducing interior heat buildup by up to as much as 40 percent. Furthermore, Lexan sheet glazing materials can help to deliver measurable return on investment through ease of installation; lower insurance costs through resistance to break-ins, weather damage, and vandalism; and less need for replacement due to UV degradation, weathering, and breakage. Most of these products are covered by a minimum 10-year limited written warranty against excessive yellowing, loss of light transmission, and loss of strength due to weathering. Of course, safety is paramount in any public building. Impact-resistant thermoplastic roofing reduces the risk of breakage from wind, hail, and other extreme weather, as well as vandalism.