Europe’s tallest building combines innovation, daring and JCT contract expertise
London: for a visual representation of JCT’s contribution to the UK construction industry, no other city houses the range of iconic projects built on JCT contracts like the capital. In recent years it seems the London skyline has been expanding to the tune of a JCT contract at its foundation. Both the Gherkin and more recently Heron Tower are examples of the City flexing its muscles with JCT at the core.
Now, a new glass giant is about to cast a long, sharp shadow over its City neighbours: with the completion of The Shard, it is not just London, but Europe that sees the most iconic building constructed on a JCT contract to date.
In a climate where stories are currently centred on construction’s decreasing output, the loss of jobs and businesses, The Shard is a defiant splinter. The Shard is a story of bombast, of innovation, of going against the current economic grain to make a cultural statement. Those who saw the recent Channel 4 documentary “The Tallest Tower”, documenting the construction process, know that many of the approaches taken to deliver this landmark were unprecedented for a UK project.
Building a 1016ft (310m) tower comprising 900,000sq ft of space between Guy’s Hospital and London Bridge station is a daunting, costly and logistically sophisticated task, yet main contractors MACE employed some exceptional techniques to complete this complex build in just four years. One example is the UK’s largest ever continuous concrete pour – 32 hours in total, during which 5,500 cubic meters (about 750 lorry loads) of concrete was poured to allow the top-down construction method (whereby work on the foundations and core can progress in parallel) to continue. A big pour on most projects would be around 150-200 cubic meters. MACE did this every hour.
As development of the core progressed, a hydraulic jump lift was used to transport materials to the increasingly difficult high working points. The lifts were capable of moving three metres per second as opposed to the half-a-metre per second speed of using traditional hoists, meaning a lot of time could be saved.
Perhaps most remarkably, the decision to set a ‘floating’ crane on top of the core rather than inside it allowed structural work to continue no matter the rate of growth. This was only the second time that such a technique had been employed on a project anywhere.
Topping Europe’s tallest building has to be done in style. The Shard’s striking feature, its ‘broken glass’ spire comprises 1300 pieces of glass and 500 tonnes of steel, which had to be prefabricated and winched into place piece-by-piece using Europe’s largest tower crane, often during challenging weather conditions.
The success of the Shard in terms of the level of innovation, design and work by the parties involved can now be clearly seen. However, it seems incredible to think how close this project came to not getting off the ground at all.
Originally let on a bespoke construction management contract, works packages for the Shard were almost finalised and let, when the recession caused the funding for the project to be pulled. With orders already placed, the outlook was bleak for the client, with the contractor on the verge of backing away. Private funding from Qatar ultimately saved the Shard project but the operation would have to be rethought, under a fixed-price scheme with a new contract.
The contract that the parties chose was a JCT Standard Building Contract Without Quantities, with Contractor’s Designed Portion (specifically SBC 2005 revision 1 2007). With enough uncertainty around the project already, and with a lengthy renegotiation having to take place, JCT seemed the natural choice. JCT contracts are well known, familiar and risks can be apportioned fairly.
Given the experience of the contractor on projects of this size and the experience of the client, the comprehensiveness of SBC was a key requirement. From MACE’s point of view, it was the best choice because the contract required needed to have a strong background, a proven history and one that could provide key default positions. It was also the most appropriate form for allocating the risks outlined in the project between the parties.
An added benefit was also the flexibility of SBC. The client had already gone a long way with the design team, and using the contract with a Contractor’s Designed Portion meant that certain elements could be handed over to the contractor for completion, with the client still able to retain overall control of the design.
It is perhaps testament to the position of JCT’s contracts within the industry that even for a project so contemporary, innovative and complex, JCT, and in particular the Standard Building Contract, remains the ‘go-to’ form. It adapts with the changing needs of the industry, yet its balance, background and proven history make it an excellent choice for when daring and innovation needs a solid foundation.
All of the work conducted on The Shard has been designed to acheive a BREEAM rating of ‘Excellent’.