There’s no beating an original
Secunda Mall
Photo: Gareth Griffiths
By Gareth Griffiths
Over decades, ZINCALUME® 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 the manufacturer.
First made in the late 1970’s, ZINCALUME has a long and distinguished pedigree, having been constantly improved over time. Manufactured and marketed by BlueScope, a reported 28 million tonnes of these zinc-aluminium coated products worldwide have been sold since inception – as verified by the Zinc-Aluminum Coaters Association (ZAC).
The 55% Al-Zn technology is licensed internationally by BIEC International Inc., a BlueScope subsidiary. In certain countries, the technology is marketed as GALVALUME®. In the mid 2000’s, the acrylic surface resin applied to coils of the product at the factory was upgraded, yielding significant advances in performance and formability.
A registered trademark of BlueScope Ltd, ZINCALUME steel was developed in association with Bethlehem Steel in the USA and perfected by Australian scientists at the Port Kembla research laboratories in New South Wales.
The choice of roofing material can affect the amount of solar energy that enters a building, affecting climate control inside the building and the comfort of occupants. To mitigate against heat ingress, ZINCALUME steel has an attractive, shiny appearance designed to keep heat out by limiting 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 continues to deliver strong thermal performance throughout the life of the product. ZINCALUME is also extremely easy to form and work with”, says Hanekom. “It stays brighter for longer and due to its lightweight steel character. It is the architect’s dream material for curves and shapes, having 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, completed in time for the 2010 FIFA soccer world cup and impressively shaped like an aircraft wing. Viewed from the air, this gives a stunning example of how versatile this product is.
The ZINCALUME roof at Cape Town International Airport is a stunning example of how versatile this product is.
Photo: Gareth Griffiths
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.
Because the metallic coating consists of 55% aluminium with the 43.5% zinc (the balance being Silicon), on a minimum coating mass both sides of 150 g/m2 in total, the user gets a highly effective degree of sacrificial anodic protection over the steel substrate meaning that the product may last at least four times longer than conventional zinc coated steels. ZINCALUME steel exhibits a more complex coating structure with both aluminium- and zinc-rich areas. The zinc-rich area provides excellent sacrificial protection, while the aluminium-rich area provides durable barrier protection. It is the combination of these two characteristics that make 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.
Mbombela Stadium
Photo: Grant Duncan-Smith
Noteworthy projects
ZINCALUME has been used extensively throughout South Africa on a number of high profile projects.
BlueScope customer, 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.
Other examples of projects have included the Mbombela Stadium, Maponya Mall, Soweto, various integrated housing projects and more recently the roof over the massive Pepkor Distribution Centre in Hammarsdale.
Pepkor Distribution Centre, Hammarsdale Photo: Reinhard Swanepoel
“If the good name of your practice is on the line, make sure our brand name is on the steel. Look for the brand that identifies the long lasting guaranteed performance of genuine ZINCALUME by BlueScope. It’s stamped on the underside of the roof sheet. Why risk your reputation by using generic Al/Zn coated steel when you can enjoy peace of mind by using genuine ZINCALUME steel?” he asks.
BlueScope Steel Southern Africa (Pty) Ltd
T: +27 21 442 5420 Arno.hanekom@bluescope.com
E: Arno.hanekom@bluescope.com