Award winner’s roofing method breaks record for longest roof span

24th November 2023 By: Lynne Davies - Creamer Media Reporter

Award winner’s roofing method breaks record for longest roof span

SOUTHERN AFRICAN MARKET POTENTIAL There is a great potential in the Southern Africa market for sky forming as a method for rolling roof sheets on site to become the new standard
Photo by: Macsteel

Manufacturer, merchandiser and steel distributor Macsteel, offering broader insight into the project that resulted in its winning three awards at the Southern African Institute of Steel Construction (Saisc) Steel Awards 2023, notes that its unique process produced “record-breaking” roofing sheets.

The Pick n Pay Distribution Centre East Port project was the joint winner of the Factory and Warehouse category, the recipient of the Innovation and Sustainability category and of the Best Project Gauteng Award.

The distribution centre used atypically long Novotexi 440 roofing sheets that ranged from 68 m to 280 m, which required innovative solutions for their handling and installation, and resulted in the project’s achieving a Guinness World Record for the longest roof span covered by a single metal corrugated sheet.

Macsteel’s unique Sky-forming method was used to roll-form the sheets directly on to the roof at the height of the roof eaves. The roof featured a distinctive curved profile with an estimated radius of 600 m that necessitated the Sky-forming process because of the excessive length, explains Macsteel CEO Mike Benfield.

“This process is unique to Macsteel and enabled us to roll one continuous length of 280 m, enabling on-site roll-forming, without any roof sheets touching the ground. This ensured that the product maintained its pristine condition and complied with the high quality standards that the customer required.”

He adds that the Novotexi 440 cladding system is a concealed fixed roofing product “designed by South Africans for the African market”, which takes the South African weather conditions into account.

The Novotexi 440’s unique attribute is its wind uplift resistance, which enables the profile to withstand wind forces of up to 3.3 kn/m2, using its patented interlocking mechanism at the male and female junction, which secures the clip system, and in turn ensures water tightness at very low pitches as low as 2º.

During roof construction, which Macsteel completed alongside roofing contractor Tate ‘n Nicholson, a system of low-friction rollers was installed to reduce friction of the 280 m sheets while roll-forming them over the roof’s curve.

This allowed for ease of installation, further enhancing the quality of the final product and speeding up the entire project. The process of Sky-forming remains an extremely efficient and much quicker process to ensure project delays are minimised or even eliminated.

“With the challenge of the long-length roof sheets merging from two different plains over the length of the roof, specifically designed flashings were critical to ensure water tightness of the building at these points, which allowed for the additional expansion and contraction properties of the two merging slopes of roof sheeting,” elaborates Benfield.

Sky forming, as a method for rolling roof sheets on site, at roof height, is poised to become the new standard in the South African market, Macsteel national product specialist Dave Reid suggests.

This method of roll-forming sheets has a distinct advantage over competitor solutions when it comes to critical path planning for large warehouse installations, as it accelerates roof supply and installation, thereby enabling contractors to meet deadlines earlier, adding value to their offering to the main customer.