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too much, but implementation of details
wasn’t great, partly because of unclear
details sent to site. That made it difficult for
everyone,” he explains. He believes that
improvements and access to technology
has greatly benefited the industry and is
quickly bringing about positive change
through transparency and clarity.
ITC-SA’s role
A roof inspector’s role isn’t well known, and their services are not often enlisted due to a lack
of awareness of the importance of roof inspections.
Booth and Ken Downhams who started
Roof Inspection Services. The pair were
trained by them and received certification.
After certification they registered with the
ITC-SA as qualified roof inspectors.
According to Bailey, the law states that if
anyone wants to erect a structure, then it
needs to be approved.
“It’s the responsibility of the owners to
recruit a qualified engineer to approve the
roof. There are two ways of getting
approval: one way is by referring to the
National Building Regulations (NBR)
deemed-to-satisfy table; however, this only
counts on simple houses with gable-to-
gable roofs that span no more than 8m. For
more complicated roofs, a designer and a
professionally registered individual who
complies with the NBR and by extension,
municipality requirements, should
be recruited.
“Second edition Construction
Regulations released in 2014, state that
every building `must have a structural
inspection every year,” he explains. This is
unfortunately not well known in the
industry and it is most often only when
there is structural failure that annual
inspections are conducted.
Bailey says that some of the buildings
he’s inspected that were built over two or
three decades ago, are now failing. “These
buildings weren’t inspected. No-one
supervised the erection, so we’re finding
unbraced roofs that are 20 to 30 years old,”
he says. The reason behind some roofs only
caving years later is because timber is a
‘patient’ material because of its
elastic qualities.
Stian de Jager explains, “A terrible roof
can take many years to fail, sagging without
owners noticing it. That’s the danger that
isn’t so well known. If timber wasn’t so
‘patient’, we wouldn’t have roofs that are
signed off so casually. Sometimes, after 10
to 15 years is when you can have a
catastrophic collapse.”
However, Bailey maintains that, with the
ITC-SA’s contribution to creating and
maintaining high standards in the timber
construction industry, things have changed.
There is now greater supervision on site
and awareness that roof inspections as well
as bracing on a roof are essential.
“On-site bracing has improved and the
process of checking it has also become
better over time,” he says. He adds that
some roof truss manufacturers go as far as
visiting the site and inspecting the roof
themselves before calling in the inspector.
Improvements that Stian de Jager has
seen include overall raised standards of
roofing. “It hasn’t solved all the problems
as too many roofs are going up unnoticed,”
he says.
He recalls that when he started it was
quite serious with site made trusses going
up for complex roofs. Thanks to the efforts
of the ITC this has greatly improved,
especially in the metropolitan areas. There
were also very poor drawings going to site.
“It was very hard to get drawings on site
to inspect what was being designed.
General carpentry skills were never lacking
As South Africa’s professional body for the
engineered timber construction industry,
the ITC-SA has also helped to educate
municipalities on the importance of
roof inspections, which have since
gained traction.
ITC-SA national coordinator, Amanda
Obbes, says that the industry is strictly
monitored, and members must undergo
annual audits through the inspectorate.
The ITC-SA also offers ongoing roof
inspector courses that are open to anyone
with a minimum of five years’ experience in
the roofing industry.
“Background knowledge could also
include quantity surveying and
architecture, although we also accept
students that are learning or considering
becoming an inspector,” she says.
The course covers basic roofing
terminology, such as rafters, tie beams,
webs, gables, hips, truncated hips, spans,
overhangs, cantilevers as well as
prefabricated / bolted methods and
addresses the basics of timber design,
including loading, information of the
relevant codes, explanations of permissible
stresses and limited state loading as well as
tributary loading.
Bracing in roofs in general is also
addressed, with a more practical look at the
differences between lightly versus heavily
loaded roofs based on field experiences
presented in visual format. In addition,
rafter bracing, including the need for
different bracing systems as well as an
overview of standard bracing details, is
also highlighted.
Course content also touches on tie
beams and web bracing, including standard
bracing details, case studies showcasing
roof failures and the reasons for these, as
well as the administrative tasks involved in
being a successful roof inspector. A general
overview of the roofing industry in South
Africa highlights the main role players in
the sector and what their responsibilities
RESIDENTIAL // COMMERCIAL // INDUSTRIAL
FEBRUARY 2018
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