Structural Renovations have recently been carrying out waterproofing works in various locations within the Shell Centre in Central London.
Our works have involved controlling water ingress within the basement and lift pit areas of the main tower.
The 27 storey tower and 3 (now demolished) 9 storey wings were constructed between 1957 and 1962, on part the site used for the Festival of Britain. At the time the tower was the tallest building in the UK and the largest office building, by floor space, in Europe.
Our first phase of works involved pouring a new screed, laid to falls, within a double width lift pit using Flexcrete Fastfill repair mortar, modified with kiln dried quartz sand. The screed and 150mm of the adjacent walls were then waterproofed using Flexcrete Cemprotec E942, a cementitious waterproof coating, prior to the lift engineers reinstalling the lift buffers and rails.
The second phase of works to 2No. adjacent lift pits was based upon a bespoke waterproofing solution designed by Parkinson VTC Ltd. The works involved the installation of a wire mesh box around both sumps within the lift pits, prior to the installation of a 400mm thick layer of 10mm aggregate, to act as a soak away. A 450mm thick layer of Flexcrete Fastfill modified with 10mm aggregate was then installed over the soakaway. The screed and 150mm of the adjacent walls were then waterproofed using Flexcrete Cemprotec E942.
The limited space on site and strict delivery periods meant that up to 4 tonnes of material were being mixed and laid by hand each day.
A major redevelopment of the area, involving new office, retail and residential space has transformed the site and 1,700 Shell staff, who were temporarily relocated to Canary Wharf, have moved back to inhabit the main tower.