South African company, Vela Steel Building Systems, played a part in enabling the fast-track construction of accommodation for athletes involved in the 10th All Africa Games, which were staged in Mozambique in September 2011.
Brent Harris, managing director of Vela, says, “The biggest challenge of this project – which was designed to house most of the 6 500 competing athletes from 48 countries – was the extremely tight construction timeframe.
“This arose after the original host, Zambia, withdrew on economic grounds, and Mozambique stepped into the breach to host the games. As a result, the normal four-year preparation cycle was effectively halved,” he explains.
Located in Zimpeto, a suburb of Mozambique’s capital city Maputo, the Athletes Village provides 848 apartments in a configuration of 27 four-storey buildings. Each of the apartments has three bedrooms, two full bathrooms, a living room, dining room, kitchen and front and back verandas. The total living space provided amounts to almost 100 000m².
“Given the sheer scale of the project and the extremely tight deadline, the main contractor – a consortium of Mota-Engil and Soares da Costa – decided to use the Worthington Construction (USA) method of cold form steel (CFS) framing as the structural system for the project,” says David van Zyl, operations director at Vela.
“This provided the speed, efficiency and strength required not only to meet the project deadline, but also to produce a high quality end product,” he adds.
Much of the cold form (or cold rolled) steel for the project was supplied by Vela – a specialist in alternative building systems – by way of road hauls from Johannesburg to site.
“By using load-bearing CFS framing members the project took advantage of steel’s greater strength-to-weight ratio, compared to traditional construction methods such as poured-in-place concrete,” says van Zyl. “The Worthington Construction Group’s framing system also incorporates innovative efficiencies in time, resources and engineering into the structure.
“The floor system is ledger-framed (rather than traditional platform-framed), which eliminates fire-blocking requirements. It also reduces time required for the installation of floor-to-floor shear connections and for layout of the floor above.”
Van Zyl says each floor is sheathed with a galvanised metal deck, which “allows the mechanical, electrical and plumbing (MEP) trades to rough in all of their work before the self-levelling floor underlay is poured.
“The unique floor underlay is half the weight of structural concrete – thus reducing floor system dead loads and allowing for a lighter foundation. The floor assembly also eliminates shoring and core drilling, allowing MEP trades to move more quickly from floor to floor,” he adds.
“Another advantage of CFS framing is the ‘panelisation’ of the load-bearing interior and exterior walls which accelerates the construction process and reduces the variability and guesswork as well as enhancing the quality of the finished building.”
The work force on the project was made up predominantly of Mozambicans and South Africans, some of whom were trained by the experienced carpenters from the USA, China and Portugal on the new framing technology.
With the All Africa Games now over, the Athletes Village will be converted into housing for residents of Zimpeto.
Vela Steel Building Systems is a member of the Johannesburg-based Duro Pressings group which is one of the biggest suppliers of steel building components used in the construction of low-cost and affordable housing.