London training chiefs say a skills shortage may hit important forthcoming projects such as the Millennium exhibition centre in Greenwich, the King's Cross Eurotunnel terminal or the proposed new Terminal Five at Heathrow Airport.
The proposed Terminal Five project, for example, will create an estimated 3,000 jobs which London training and enterprise councils want to stay in the capital. They are working on a training drive to make sure London gets its share of benefit from the predicted boom.
However, the problem is compounded by the fact that high-tech buildings require advanced construction techniques and skills. West London TEC executive director Vince Taylor said: "It's a little bit like building Meccano rather than working with bricks and mortar, so the skills required are a little bit different from conventional building.
"At present the industry is telling us that no British company could build Terminal Five.
"Some large firms feel a little bit easier than we do. They feel it's a flexible industry, but we are a little bit more concerned."
TEC officials are anxious not to train workers for a major building project, only for them to become redundant once it is complete. But the expected demand for a series of major new buildings in the capital has encouraged them to invest large sums to train workers and to help firms tender for contracts.
West London TEC is working on a scheme to set up a permanent training centre for the building industry in Hounslow, near Heathrow, and has prepared plans to advise 300 companies on tendering and to run training schemes for 500 people. It has attracted Pounds 1.2 million Government funding to the programme and is looking for another Pounds 1m from European sources Last year the Construction Round Table, a group of the industry's leading customers, found training had slumped to such an extent that foreign workers may be needed to bridge the skills gap produced by an upturn in demand.
And earlier this week the Construction Industry Training Board launched its biggest careers campaign to date amid fears that too few school-leavers are joining the industry.
Construction industry leaders are down-playing fears of a skill shortage, pointing to the immense flexibility of the workforce prepared to travel far for a slice of the work generated by major projects. But they acknowledge that business and civic leaders often want to help firms keep the benefit from major schemes local.
Peter Rainbird, vice-chairman of the CITB and chairman of Essex TEC, said there was potential for a skills shortage, if the building industry encountered rapid growth.
But he said local skills gaps would be filled by the national pool of labour. "Construction workers are very mobile and if there's work in London they go to London. But five, six and seven years of recession and the labour force does get run down. The CITB is concerned that it's difficult to find the right number of young people of the right calibre to come into the industry.
"There's obviously the potential for a skills shortage - a serious one - if we get above average growth. But I do not see that sort of growth coming."