Brookfield has decided on a concrete core for The Pinnacle, set to be the City of London’s tallest building
Plans for the City of London’s tallest building The Pinnacle have been altered to include a concrete core, with prequalifying for the subcontract package underway.
Australian contractor Brookfield, who is building the 63-storey 288m tower in Bishopsgate, decided the previous steel frame design would be strengthened with the addition of a concrete core.
On 15 January Brookfield, formerly Multiplex, took control of the project from Mace who had overseen the demolition and groundworks for more than a year under a construction management deal.
Brookfieldcarried out a pre-construction service on the project bringing in high rise experts from Dubai and Australia to pore over the plans.
Construction director Ian Pratt said: “We felt it was better to have a concrete core. It gives a much stiffer back bone to the building. We haven’t let out the concrete package on this yet. At the moment we are prequalifying for the package.”
The change means less steel will be required from Dutch contractor Hollandia, which worked with Brookfield on Wembley Stadium, and Belgian firm Victor Buyck who are carrying out steelwork as a joint venture, having previously worked together on the Gherkin.
Once a firm is appointed for the concrete package, all subcontracts will have been tied up, with Gartner having won the cladding, T Clarke the electrics, Schindler the lifts and MJ Lonsdale taking the mechanical packages.
Piling work - being carried out by Bachy Soletanche - is progressing well with 100 of the 120 record breaking piles in the ground.
The piles, with the interior sizes up to 2.4 metres in diameter and sufficient to contain 229.16 cubic metres of concrete, are being sunk 65.5 metres below the ground level of the site setting a new record for foundation depth in London.
The remaining 20 piles will provide about another three months of work while Keltbray has nearly completed the demolition work required on the site.
Brookfieldhas agreed a guaranteed maximum price for The Pinnacle, believed to be around £575 million.
Construction is split into two phases – work up to the ground floor level, which will take another year, and then building the super-structure which is expected to be completed by 2013.
Mr Pratt said: “You won’t see anything above ground before about September 2010 which gives you an idea of how much work will be going into the three level basement. The Pinnacle will reach peak height in the back end of 2012.”
Four tower cranes, topping out around the 1,000 ft mark, will be erected at the site by the end of this year.
They were sourced in Australia and are being made in Malaysia and have the ability to be locked in place so that they stay secure in high winds.
Mr Pratt said: “We have restrictions in terms of height because the site is on the flight path.
“It is one of the biggest challenges getting the guys up to the workface. At peak around 1,500 people will be working on the construction.”