Over the years the prestigious Steel Awards, hosted annually by the Southern African Institute of Steel Construction (Saisc), has been an excellent barometer of the growth of the Light Steel Frame Building (LSFB) in Southern Africa. This year was no different. Nineteen projects were entered into the LSFB category by seven leading Southern African Light Steel Frame Building Association (Sasfa) members from seven provinces around the country. The majority – 25% – came from Gauteng, with KZN 20% and 15% each from OFS and Eastern Cape.
Sasfa director John Barnard says that while the quantum of entries is an indicator of how the industry is faring, the floor area covered by the entries is a measure of how the industry has transformed since LSFB first became a category in the Steel Awards 10 years ago. It reflects the trend towards larger projects being built using LSF.
This year, the LSFB entries comprised 30% residential, 30% community buildings and the rest in office / commercial and industrial projects
“It is pleasing to see the growth in LSFB use in the residential sector,” says Barnard. “Home owners have accepted that LSF buildings appear no different to ‘conventionally’ built structures and that the quality of finishes is typically better. They also realise that LSF is a very cost-effective building method, with financial savings emanating mainly from significant time savings to complete building projects, less rework, reduced logistical costs –which are of growing importance due to the escalation of fuel prices and general construction inflation – and a drastic reduction of rubble on building sites, when compared with the brick-and-mortar alternative.”
When analysing the LSFB entries for Steel Awards 2017 during the judging process, Barnard says it was interesting how different entries represented different attributes of LSFB – logistics playing an important role in the more remote projects, low mass being important in the construction of long-span roof trusses, while speed of construction the key for most of the others.
2017 Steel Awards LSFB Winners
There were two joint winners in the MiTek LSFB category at Steel Awards 2017 –
GLA School Hall and Summit Place:
With several two and three storey office buildings at Summit Place, Garsfontein, Pretoria, already successfully clad with LSF façade walls with ETICS external cladding, it was no surprise that architect Boogertman & Partners, decided to use the same solution on the Assupol Building – the 11-storey winning office block -, in the same development.
In most of the earlier Summit Place buildings, the architect specified slanting, gravity defying façade walls. With the Assupol Building, he decided to introduce elegantly curved façade walls, made possible by LSF.
This is the first and highest South African high-rise office building where façade walls were constructed with LSF and ETICS external cladding. Saint-Gobains’ ETICS was used for the external cladding, as it is suited to curves, provides a durable external finish as well as insulating the office building to reduce the energy required for heating and cooling over the lifetime of the building.
Barnard says that this project amply portrays the benefits of LSFB. “The façade walls were built quickly and accurately with, for example, all of the 700 pre-made external windows fitting perfectly into the pre-designed openings in the wall panels. The low mass of the LSF and ETICS cladding eased logistics, and made handling on site a lot easier, requiring only a small team of artisans to do the installation. Also, importantly in these circumstances, the low waste factor meant a small operational footprint allowing other trades to work in tandem.
“This project is aesthetically pleasing and uniquely captures most of the benefits of LSFB,” says Barnard.
GLA School Hall
The main challenge of this Jeffrey’s Bay project was to establish a world class green education facility on a tight budget. This required architect, Jacobus Scott, to come up with innovative solutions especially because the owners wanted a multi-use gathering area, which required along span roof design. “The MiTek Ultra-Span system was perfect in these circumstances,” says Barnard. “The MiTek team designed and installed a cost-effective solution that not only looks impressive, but also effectively solved design and engineering problems that could never have been overcome with a traditional roofing system.”
Barnard adds that what struck him about this project was how closely the final structure resembles a sketch drawing used originally to promote the solution! “This is not the lowest mass per area roof structure, but some clever design captured benefits made possible by high strength low mass steel trusses. From natural ventilation to optimisation of natural light, photo voltaic cells and rainwater harvesting and the recyclability of materials used – LSF – made this green structure possible”.
“While these two are worthy winners, all the entries were of an exceptional standard and reflected the quality and excellence of an industry that is becoming increasingly relevant in a construction environment that is facing rising costs in materials and transport and in an end-user environment where energy costs are soaring and environmental issues are paramount,” Barnard concludes.