Over decades, ZINCALUME® steel has become a household name within the building industry. When specifying premium high performance metallic coated roofing and cladding materials, this original and trusted brand remains the roofing material of choice for specifiers, says Arno Hanekom, the BlueScope Steel Regional Manager for Africa and the Indian Ocean Islands.
The product’s 55% Al-Zn technology is licensed internationally by BIEC International Inc., a BlueScope subsidiary. In the mid-2000s, the acrylic surface resin applied to coils of the product at the factory was upgraded, yielding significant advances in performance and formability.
The choice of roofing material influences the amount of solar energy that enters a building, affecting climate control and building comfort. To mitigate against heat, ZINCALUME® steel has an attractive, shiny appearance designed to limit solar absorptance. All roofing products are subject to weathering, however, BlueScope’s product will stay brighter for much longer than alternatives, providing approximately twice the thermal performance of other commonly used materials such as weathered galvanised steel and fibre cement/asbestos.
“ZINCALUME® steel delivers strong thermal performance throughout its life. It’s also very easy to form and work with”, says Hanekom. “It stays brighter for longer. Due to its lightweight nature, it is the architect’s dream material for curves and shapes. It’s been formed into a variety of curved surfaces. A good example of this is the roof over the departures terminal at Cape Town International Airport which is shaped like an aircraft wing.
The corrosion-resisting benefits of the product are considerable, and a special AZ 200 (both sides coated with 200 g/m2 of Al-Zn coating) version is available for use within the 5 km distance of the sea or in areas where there is a strong industrial fallout. Lifetime in service reported as being four times longer than conventional galvanised sheeting. The metallic coating consists of 55% aluminium with the 43.5% zinc (the balance silicon), on a minimum coating mass both sides of 150 g/m2 total. ZINCALUME® steel offers a complex surface with both aluminium- and zinc-rich areas. The zinc-rich area provides excellent sacrificial protection, while the aluminium-rich area provides durable barrier protection making this unique product durable and effective against corrosion. “All this means that a special corporate warranty of performance can apply when product is fitted in an approved way”, adds Hanekom.
ZINCALUME® has been used extensively throughout South Africa. Clotan Steel expertly formed ZINCALUME into its Craft Lock profile in use at the Secunda Mall, as specified by architectural firm, LP Architects. The double-story mall was completed late in 2013.
“If the good name of your practice is on the line, why risk your reputation by using generic Al/Zn coated steel when you can enjoy peace of mind by using genuine ZINCALUME® steel?” asks Hanekom.