FEATURES
greater care than a structure inland,
for example.
While some roof systems call for less
intense maintenance than others, all
roofing systems should be checked
periodically and maintained accordingly,
advises the Institute for Timber
Construction South Africa (ITC-SA).
Regarded as the professional body for the
engineered timber construction sector, the
ITC-SA provides design, manufacturing,
erection, inspection and certification for
compliance with inter alia SANS 10400 and
SANS 10082, where engineering rational
designs are applicable.
In the case of nail-plated timber roof
structures, legislation stipulates that they
should be designed, manufactured, erected
and inspected by ITC-SA accredited
members who have been awarded a
Certificate of Competence. An A19
Certificate will be issued on compliance,
which is required by the local authority
before issuing an occupation certificate.
Best practise
In maintaining roof structures and industry
standards, the ITC-SA offers CPD-accredited
roof inspection courses. According to ITC-SA
general manager Amanda Obbes, the Roof
Inspection Training Course offered by the
institute comprises an intensive theoretical
and technical overview of timber
roof structures.
“Students are exposed to basic
terminology and timber structure design,
framing and bracing, design consideration
for light and heavily loaded timber roof
structures, manufacturing, transportation
and storage, and the various timber roof
structures and types of buildings. Further to
this, students get first-hand, up-close
experience with the roof inspection
process, as they venture onto two different
construction sites which demonstrate both
correct and incorrect roofing practices,”
she explains.
Obbes continues, “The course is designed
to enable: any technical person to conduct
roof inspections with knowledge and
insight; registered professionals to sign off
roofs on their own, knowing they speak
with authority; and individuals with
experience in the roof construction industry
to be sufficiently trained to inspect roofs
under an accredited ITC-SA
professional engineer.”
www.saroofing.co.za
“
If the roof exterior
is beginning to collect
moss or algae, consider
installing zinc or lead
control strips to help
control the problem.”
A certified roof inspector is defined as a
practicing professional who will
traditionally come from the built
environment, must have prior experience in
roof design and construction, and should
preferably have a recognised qualification
(NQF level 5) in the built environment.
Civil engineer Thea Smal highlights there
are many players out there designing and
manufacturing without any guidance or
regulation. “The ITC-SA courses have taught
me a great deal and have helped me to
bridge the gap between what I learned from
university and the practical application
thereof. I believe that being associated with
a professional body like the ITC-SA that
helps to regulate the industry is very
important,” notes Smal.
Making
maintenance priority
Based on expert industry knowledge
provided by MiTek Industries South Africa
and International Truss Systems, the best
preventative measure one can implement
in the care of a roof structure is to conduct
regular inspections to help identify and
remedy problems as and when they occur
– preventative maintenance is pivotal in
saving money on a roof by providing a
longer service life.
When it comes to the roof’s exterior, be
sure to check for any cracked roof tiles,
loose sheeting and loose roof screws. These
may cause leaks, which have the potential
to cause damage to the interior timber of
the roof structure and prompt or accelerate
wood rot. At the same time, look for open
areas around newly installed antenna
shafts and chimneys; while waterproofing
should be installed to prevent any leaks,
the condition of the waterproofing
membranes must also be inspected
regularly. Crumbling chimney mortar could
also signal moisture penetration and will
need to be reapplied.
Timber roof overhangs are most
susceptible to the elements and should be
maintained regularly to prevent fungal
attack or rot from moisture. Loose fascia
boards and leaking gutters are the most
common cause of leaks onto roofing
timber. On this note, be alert to any creeper
plants growing onto the overhanging roof
timbers. Keep all gutters free from debris
and make sure the downpipes are draining
properly by water testing them.
If the roof exterior is beginning to collect
moss or algae, consider installing zinc or
lead control strips to help control the
problem. These strips form harmless zinc
oxide when rainwater runs over them, in so
doing, carrying with it a coating preventing
further moss or algae growth from occurring.
Check all flashings, making sure they are
not deteriorated and be sure to secure or
replace any loose shingles. Trim back any
overhanging tree branches and check any
metal on the roof for signs of rust. Pay
attention to all caulking and sealants, and
scrape and remove any caulking that is
weathered, cracked or damaged, and
reapply. If the roof has gravel surfacing, be
alert to any bare spots, otherwise, check for
blisters in the roofing material.
Salt or dirt build-up can encourage rust
on steel roofs, and moss and lichen growth
on tiled roofs. Some manufacturers’
warranties advise regular washing,
particularly in areas that don’t receive
frequent rain. Frequent washing and
inspection are advised to prevent salt and
dirt build-up. Exposed timber trusses must
be treated for exposure to the elements.
Cracked timber components in the roof
structure are the first warning signs that
something within the roof structure is
deteriorating. Inspect all the components
of the roof structure after new services, like
plumbing, electrical and/or a fireplace, are
installed. Check the interior of the roof for
any leaks; these may be indicative of a
leaking roof membrane.
If timber is beginning to show signs of
rot, painting it will only worsen the
situation. In this case, it is advisable to
replace the affected timber. Painting and
repainting should only be done on healthy
timber surfaces. Be sure to adhere to the
paint or treatment specifications
concerning the application.
Additions, such as a cooking canopy that
extracts smoke or steam from the kitchen,
CLADDING // CONCRETE // INSULATION // STEEL // THATCH // TIMBER // TRANSLUCENT // WATERPROOFING // COMPONENTS
NOVEMBER 2018
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