FEATURES
The roof trusses of the Kingdom Leadership Centre in Middelburg, Mpumalanga were erected in one day.
What makes this building method attractive,
you may ask? Barnard says the major
advantage is that there are very few
disadvantages. “This building method
boasts logistical advantages due to the low
mass and transportability of light steel
frame sections, ease of handling on site, the
inherent accuracy, and the reliability of
mechanical properties. All of these factors
combine to make it cost-competitive.
Light steel frame building is often used
for vertical extensions as the low mass of
the floor joists and walls more often than
not render the existing foundations
adequate for the increased load. Barnard
highlights that truss spans of more than
30m is possible, opening up competition
with heavy welded hot-rolled structures.
Where required, hot-rolled sections are used
in combination with light steel framing for
extreme spans, he says.
“Long span trusses are very slender and
difficult to erect one by one. MiTek, one of
the major light steel frame suppliers in this
segment, has, in conjunction with their
licensees, devised a process to overcome
this problem. They box groups of trusses on
the ground with bracing and purlins and
then lift these clusters of trusses onto the
building using a long reach, low mass crane.
www.saroofing.co.za
It is safer, as much of the work is done at
ground level, and quicker. As an example,
the roof trusses of the 3 200m² Kingdom
Leadership Centre in Mpumalanga were
erected in a single day!”
Frame of reference
Provided the foundations or floor slabs have
been cast accurately and level, installation
of wall frames and roof trusses can take
place rapidly, using a small team of artisans,
says Barnard. “For instance, wall frames and
roof trusses for a 250m² house can be put
up in three or four days, by a team of four
artisans. While it is easy to erect, it has to be
done correctly, and SASFA strongly
recommends the use of competent and
trained builders.”
Most of the materials used are
incombustible, and hence do not propagate
fire, notes Barnard. “Fire resistant gypsum
board is used for internal lining to protect
the steel against the heat of internal fires.
The light steel frames are designed to resist
high wind speeds – from the roof trusses
and their connection to the wall panels,
through the bracing in the walls to the
anchoring of the wall panels to the floor
slabs or foundations,” he highlights.
“The materials used for light steel frame
building are not cheap, but as a package,
with all its advantages, it is cost-competitive
– otherwise the use of light steel frame will
not be expanding,” states Barnard. Having
said this, he believes the future of light steel
frame building in South Africa looks bright
and promising.
“The steel industry recently hosted the
Steel Awards, where 19 light steel frame
projects were submitted. Apart from the
light steel frame category winner, Gateway
West, there were a number of eye-catching
projects including a game lodge in
Botswana; the vertical extension of Kaap
Agri offices in Paarl; the roof of the
Mediclinic in Stellenbosch; the Spectacle
Warehouse in Pretoria; and several light
steel frame houses built in Knysna in
response to the needs after the terrible fires
in 2017.
“We are busy with changing mindsets
within the industry. I do believe that five
years from now we will see light steel
framing as a conventional and standard
building method – let’s face it, it is the
logical way to build, designed to overcome
all the disadvantages of masonry building. It
is quick, accurate and neat, with minimum
wastage. Within a few years it will be the
preferred way of building. It is the future.”
CLADDING // CONCRETE // INSULATION // STEEL // THATCH // TIMBER // TRANSLUCENT // WATERPROOFING // COMPONENTS
JAN - FEB 2019
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