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CONSTRUCTION WORLD
FEBRUARY
2017
not intrude at all into public space.”
He says the luffing jib concept offers
the advantage of allowing the operator to
traverse up and over a building or another
crane, pick up material, luff back over again,
and place the load where it is needed.
“It is unlikely that South African cities
would ever have to impose London-type
regulations on crane use, but it does prove
the point that – in terms of practicality – the
luffing jib crane will be the way to go as our
building spaces become tighter,” he says. “In
fact, our first luffing jib crane is at work on
the Village Walk redevelopment in Sandton.”
Hoists
Hoists represent another lifting technology
that Van Breda hails as important for the
future of contractor productivity, and he
says they are growing in popularity as their
advantages become better known. He says
hoists are particularly suited to the latter
phases of a building project.
Hoists represent another lifting technology
that is important for the future of contractor
productivity. The hoist’s advantage is that it
can also convey passengers.
“Once a tower crane has completed its
work on the superstructure of a project – in
other words, the concrete and brickwork
– most of the remaining work involves
the finishing trades,” he says. “The main
components being moved at this stage here
include items like window frames, doors,
cladding and tiles. Why would you use a
tower crane on this part of the job, when a
hoist could just as easily do the work more
economically?”
By erecting a hoist for the tradesman
and materials involved with the finishing
trades, a contractor could release one or
more of the tower cranes active on that job
earlier – thereby saving substantially on
rental fees. Even if the contractor owned the
tower crane, it could be relocated to more
profitable duty elsewhere.
The hoist’s advantage is that it can also
convey passengers; productivity is boosted
by hoisting workers up to the higher floors
quickly, rather than the time-consuming
exercise of walking upstairs or even using
scaffold to ascend.
“It is a surprisingly common occurrence
for workmen to be required to walk to the
working areas on the 25
th
floor of a building
– even though just one trip could easily
waste half an hour of the working day,” he
says. “Add to that the time taken to come
down again for lunches and breaks, and the
work-day becomes substantially shorter.”
One reason is that the installation of the
lift systems in new buildings is frequently
one of the last items of infrastructure to be
commissioned – and even if the lifts are
completed in time for workmen to make
use of them during construction phase, the
owners or suppliers may not allow this for
fear of damage to the new installation.
“Using a carefully planned combination
of different crane and lifting options will
optimise the plant used on a contract – so
that site productivity can be increased and
costs reduced,” says Van Breda.