Construction World June 2019

blockages within the pipeline were avoided and work could progress smoothly. Finishing trades The parking ramps that form the north section of the podium, were constructed using Skydeck formwork to enable quick installation as well as removal as these areas were to be used for interim storage and manufacturing areas during construction. Normal formwork was used for each slab in the tower. Using a method familiar to the workforce enabled a labour intensive but efficient process, enabling prompt access for following trades. Minimal scaffolding was used so that it could be disassembled quickly to allow for finishing trades to move onto the levels. McInerney asserts that the design ensured that, “All following trades could be built from the inside, in a covered space relatively free from the effects of the weather”. Light, aerated concrete blocks and drywall systems, as well as some traditional brickwork, form demising and partition walls. The design allowed for two cranes to be positioned at opposite corners of the

tower. The height and reach of each were carefully programmed to ensure optimum use with each radius accounted for. These were primarily used for the construction of the structure. All internal components and materials were loaded at night onto staging platforms at approximately every fourth level, allowing the cranes to be fully occupied with the primary construction during the day. “Designing light weight components and elements for the interior and façade that could be handled by labour rather than requiring hook time on the crane, freed up the crane and enabled an eight day cycle for the construction of each structural concrete floor,” says Malika Walele, Co-Arc’s Site Representative. The façade The façade was constructed entirely from the inside of the building with no scaffolding needed on the outside, significantly reducing risk and creating significant cost savings. With the site running on a 24 hour schedule, and the material needed for the façade to be loaded onto the floors at night, the façade could keep pace with the overall

construction. Each section of the façade could be assembled on the respective floor and then winched out and fixed outside from the floor above. Dekton (12 mm) was used. This weighs less than the granite traditionally used for façades, which meant that the entire façade could be constructed with minimal machinery and instead made use of labour. The small footprint of the site and height of the building meant that vertical circulation of material and people had to be carefully programmed for every hour running on a 24 hour schedule. Loading of material on site was prioritised during the night by means of crane and hoists. Almost 2 000 people were employed by the project. During daytime rush hour the two temporary hoists, one internal and one external, were used for the movement of people through the building with material being loaded in between. After months of watching the building grow, it will be strange to see this new landmark stop growing and become still on the horizon, slowly becoming a concrete presence in the mental map of Joburg. 

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CONSTRUCTION WORLD JUNE 2019