To allow Eastgate Shopping Centre in Gauteng to upgrade its heating, ventilation and air-conditioning (HVAC) facilities for greater energy- and water-efficiency, Concor is carefully strengthening the structure on which the heavy new chillers will rest. Concor contract manager Martin Muller explains that the HVAC system is located on top of a building on the centre’s roof parking area, in which tenants are active – and need to continue trading during the renovation. Aside from the technical elements of the contract, therefore, clear and ongoing communication with the client and the tenants is a crucial aspect of success.
“The construction work includes the demolition of an existing roof, walls and slab above tenants,” says Muller. “The structure will then be strengthened to ensure that it can safely carry the seven 10-ton HVAC chillers which are to be installed on the rooftop building.”

Due to the presence of a tenant running a call centre in the adjacent building, demolition can only take place outside of normal working hours. Muller highlights the importance of Concor’s safety culture in ensuring safe working practices at night. What is important is for the considerable load of the new installation to be effectively transferred into the centre’s existing concrete columns under the
roof parking – and hence down into the foundations. This is being done through the construction of interlinking stub columns which will create a grid to support the chillers. These columns are being cast
systematically, working in a direction of priority for the HVAC specialists, so that they can start their installations on the network of support steelwork and grating which Concor will provide.

The new structure will also include a transformer room and a perimeter louvre closure around the HVAC area. At about 3,5m high, the louvre will improve the rooftop aesthetics by concealing the installation from view. Concor’s team and sub-contractors receive working-at-height training and work strictly according to safety protocols – especially since the HVAC rooms are 8,5m above ground on one side of the structure and 20m high on the other. Completing the project will be a steel roof, louvres to allow fresh air to cool the installation, access doors and a steel staircase.