For the construction of the roof structure of Phase 4 of Mediclinic Vergelegen in Somerset West, a non-combustible material, which could support solar panels while at the same time bear the weight of theatre equipment, was required.
Steel was envisaged from the outset, based on the success of previous healthcare facility projects. Since MiTek’s Ultra-Span has the ability to clear span up to 40m, this pre-fabricated light gauge steel roof truss system was selected. Both lightweight and compact, Ultra-Span is also economical to transport.
Using inverted shape trusses of MiTek Ultra-Span components ranging between 14m and 20m clear spans, the structural framing consisted of cold-rolled, specially designed sections of various profiles and thicknesses, cut to length with one-sided assembly. The inverted shape roof trusses provided a structurally sound roof design to accommodate services and solar PV panels to the one elevation of the roof structures.
The trusses were manufactured in Rooftek’s factory before being transported to site. Roof sections of approximately 150m² could be assembled before being lifted into position.
An optimised design
Jaco van Wyk from MiTek Engineering Cape Town created a cost-effective framing solution. The erecting of the roof structure was simplified by assembling portions on the concrete slab and lifting the required sections into place. This enabled optimisation of connections of the trusses, permitted services to be connected and reduced torsional moments on the concrete ring beams.
No challenge too big
The roof structure was detailed to be supported in-between the concrete ring beams on brackets. In some places the trusses were supported on the reinforced concrete beam.
This, together with the box-gutter detail that was required, additional steel sprockets that had to match the existing ones and the overall design that had to fit seamlessly with the previous phases, created some challenges during the design, costing and erection phases. However, close collaboration between MiTek, TV3 Architects and Rooftek on all design complexities eliminated many potential problems prior to the manufacturing and erecting of the roof structure.
“It is a huge advantage to have Kalahari on anyproject team,” comments Hennie Viljoen, regional and marketing manager at MiTek. “He is brilliant at what he does and he uses Ultra-Span in the most innovative ways.”
Phase 4 of Mediclinic Vergelegen in Somerset West was also nominated for the 2019 SAISC Steel Awards. MiTek customers has won the highly contested Light Steel Frame Building category in 2010, 2015 and 2017 with Ultra-Span nominated projects.
MiTek Industries South Africa
Tel: 011 237 8700
Client: Matec Construction
Architect: TV3 Architects and Town Planners
Roofing and cladding: Global Roofing Solutions
Tons of LSF used: 27 248,85kg
Span of trusses: 15 920m
Completion of LSFB work: 2019