Mediclinic’s light steel frame roof structure was commended for its strength, low mass, efficiency, cost-effectiveness and ease of construction in the Steel Awards.

In designing the award-winning light steel frame (LSF) roof structure for Mediclinic Midstream, MiTek’s aim was to keep the load on the supporting structure as low as possible while containing all the necessary hospital services.

The Mediclinic project was a joint winner of the light steel frame building category, amongst a record number of entries in this category this year.

The Ultra-Span® light gauge steel truss system covers 9 100m² of the roof and weighs almost 68 tons, just below 7,5kg/m², including purlins. “Being one of the merits of Ultra-Span®, this is extremely light considering the significant loading on the roof due to all the necessary hospital services, and the fact that some of the roof trusses span 19m,” says Uwe Schluter, business development manager at MiTek.

The design also allowed for supporting 100mm- FBI insulation between the truss top chords and the purlins.

On-site manufacturing
Hi-Tech Nail Plate supplied and installed the roof structure, manufacturing most of it on-site, especially the long-span Ultra-Span® trusses and girders, eliminating transport difficulties and saving time.

According to Dave Anderson, managing director of Hi-Tech Nail Plate, clusters of four large trusses were assembled into braced roof sections on the building slab. These big, prefabricated roof portions were then hoisted into position using the site tower cranes and were then connected together to form the final roof structure.

“The magnitude and the size of the span made it a very interesting and challenging project,” he comments. “The programme, as on most builds these days, was very tight and that is where the Ultra-Span® product came into its own for speedy erection.”

While the overall project program ran over a few months, with the roof being put up in blocks, each section of the roof was constructed within only two to three weeks. The fact that most of the trusses were fabricated on site, also sped up the process.

Anderson adds that efficiency was another deciding factor in choosing this type of roof and the overall cost at the end of the day proved it to be the most economical solution for the project. The cost of the light steel roof structure was approximately 25% lower than timber trusses, and approximately 30% lower than the cost of a conventional structural steel roof structure.

Judges’ comments
The Steel Awards judges cited this project as an excellent testimonial for light steel frame roofing. “It illustrates all the beneficial aspects of steel – formability, guaranteed high strength, low mass, straight and true elements, narrow tolerances, ease of transport, handling and erection, with life-long corrosion protection supplied by the thin zinc coating,” they commented.

MiTek Industries South Africa
Tel: 011 237 8700

Hi-Tech Nail Plate
Tel: 011 392-6473