Skyscraper boom comes crashing down to Earth

When Boris Johnson inaugurated The Shard, the Mayor hailed Britain's tallest skyscraper as "a symbol of how London is powering its way out of the global recession".

But The Shard has yet to secure its first tenant whilst six other landmark additions to London's skyline may now never be built, developers have warned, as a mania for ever-taller buildings comes crashing to Earth.

A sluggish property investment market has brought plans to build six ambitious new testaments to the capital's supposed economic self-confidence juddering to a halt.

Construction of 100 Bishopsgate, a 172 metre skyscraper, planned to be the tallest in the City of London, is among those which have been postponed or cancelled, a BBC Inside Out investigation found. A lack of advance tenants has frustrated the builders.

The £1bn Pinnacle – nicknamed Helter Skelter – would have been the UK's second-tallest skyscraper. Plans for a "futuristic office block" called Trinity have also been quashed.

The so-called "Can of Ham" was approved in 2008 but the building on its site has not been demolished yet. And the £450m, 310-metre Shard did not have a single financial tenant to occupy its 600,000 sq ft of office space when it launched in July. Its developer, Irvine Sellar, predicted it would be fully leased by the end of 2014.

Peter Murray, chairman of London's Centre for the Built Environment, remained optimistic. He said: "I've seen four recessions during my career and in each one I've heard people say, 'Look at all this empty office space, why do we need it?' And after each one as the economy has improved, it has become occupied."