Development of specialist screed for The Shard

The Challenge

The original material specification called for a site batched screed to be used which meant the physical transporting of plant and heavy materials in small quantities in the jump lift. Progressive Group, who were contracted to install the screed, needed a more logistically friendly solution which also drastically cut installation times and so called in the materials expertise of Pozament. Due to the building’s busy London location, continuity of transport of materials to site was crucial. Once screeding started, interruptions in material supply were simply not an option.

Our Solution

The standard screed material was normally only pumped up to a maximum of 10 storeys, so tests were conducted in order to find the right blend of materials to cope with the massive 75 bars of pressure exerted in pumping the screed so high. Extra binder was added to the screed mixture to prevent separation and this allowed the product to be pumped through a 5 inch pipe to most parts of the building. The concrete pump used was also modified to allow for this work to be carried out. Delivery vehicles were finely co-ordinated so that at any one time there were three mixer vehicles in use for the project ensuring a continuous supply.

Results and Benefits

The 72 storey, 310 metre building was started in March 2009 and completed in April 2012. Pozament have an impressive track record of supplying specialist materials to some of the most challenging construction projects of recent decades and this one was no exception. The extreme challenges of this project resulting from the height of the building and the pressures involved in pumping the material required specialist knowledge to develop a solution that would work. Choosing Pozament as a materials supplier, gave the client reassurance that the material developed and supplied would have been thoroughly tested and would perform as required.