Main contractor Laing O’Rourke has built 85% of the structure (by construction value) off-site. The building, designed by architect Graham Stirk of Rogers Stirk Harbour + Partners, has 18,000 tonnes of steel and 70,000 square metres of cladding. However, for structural steelwork contractor Severfield-Rowen, it has not been a happy project; overruns on the project have cost it £10m.
Nicknamed the Cheesegrater, the 238m-high tower has been under construction in the City since early 2011 and is scheduled to complete in summer 2014.
The building's distinctive tapered profile has been designed to protect the sight line of St Paul's Cathedral. Unusually for a tall building, the Leadenhall Building has no central core, with an external mega frame providing the lateral stability and the 26 passenger lifts housed in the building's Northern Core, painted bright yellow, at the rear of the building.
At ground level, its half-acre footprint will have a seven-storey galleria with a shopping mall as well as a public events space.
The 47-storey building is owned by a 50:50 joint venture of British Land and Oxford Properties.
Mayor of London Boris Johnson said at last night’s ceremony: "The Leadenhall Building is the latest landmark to grace London’s iconic skyline, demonstrating our city’s ability to design and construct world-class architecture. This ambitious project has created jobs in London and elsewhere across the UK supporting great British manufacturing all over the country. The building’s soaring pinnacle symbolises the confidence in London’s status as a global centre of finance and trade."