Construction World February 2017

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.

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.

“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. 

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CONSTRUCTION WORLD FEBRUARY 2017