the national overall winner of the Steel Awards as well as the SA Construction World 2011 Best Project for the Civil Engineering and Building Contractors award .
Brief Sandton City is owned by Liberty Properties and Pareto Limited . The owners had a vision to reposition the Sandton City complex as a worldclass destination that would differentiate it in southern Africa .
Tia Kanakakis , a partner at MDS Architecture who has also worked on previous refurbishments and extensions to the complex , says that the brief for Phase 1 was the addition of more retail space and to effect a design that would reposition Sandton City as the leading retail development in SA - the design was to include the refurbishment of the existing mall , the reduction of energy consumption and improvement of shopper flow .
Protea Court ’ s Unique Roof Light The Protea Court formed a key component of the design . “ The intention of the court was to create a unique element in the shopping centre precinct that would excel in every design aspect ,” explains Kanakakis .
The design of the court was inspired by the Protea flower , with the lift shaft acting as the stem of the flower , topped by a petal-like canopy in the form of a roof light . The pedestrian entrance features what is believed to be the largest curtain wall area of suspended structural double-glazing glass in South Africa , providing a dramatic backdrop to the 8-storey court .
The roof light presented an opportunity to use new technology in the form of pneumatically inflated cushions to form the roof . This product , known as Texlon , is made up of multiple layers of foil known as ethylene-tetra-fluoro-ethylene ( ETFE ), a modified polymer . Texlon made its debut in South Africa on the Protea Court roof .
“ The material translated the dynamic design intent of the dome design and , at the same time , provided a suitable lightweight technology for use over the centre when the remainder of the Sandton City master plan is to be implemented ,” explains Kanakakis .
Texlon consists of pneumatic cushions restrained in aluminium extrusions , supported by a lightweight structure . The cushions are inflated with low pressure air to provide insulation and resist winds .
Kanakakis says that an added benefit is that the material does not degrade under ultraviolet light or atmospheric pollution and is translucent , allowing natural daylight to penetrate the voluminous space . “ The product is also very attractive as a result of its contribution to lower cleaning and maintenance costs . Texlon self-cleans when it rains and , should the lightweight pneumatic cushions ever be dented by hail , they revert to their original shape when heated by the sun ,” she explains .
The roof itself includes a combination of contrasting translucent and white sections . This combination was selected for aesthetic reasons and to manage the thermal transmission that affects the court ’ s heat load .
The ambient temperature within the Protea Court has also been controlled through the use of double structural glazing - another first for South
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