A slowdown in construction growth following the EU referendum will reduce the number of workers needed by 2020 by a third, according to the CITB.
Construction output over the next five years is expected to average 2 per cent, the CITB’s latest Construction Skills Network report shows.
This is down from the 2.5 per cent forecast in January’s CSN report.
As a result, the CITB has revised down the number of workers needed by the sector by 2020 to 157,000, compared with a forecast of 232,000 in January.
CITB director of policy Steve Radley said the figures reflected the uncertainty caused by the Brexit vote.
He added: “Delays and uncertainty over investment decisions and access to migrant labour will likely intensify as Brexit nears.
“While employers’ main focus in the short term will be to weather the storm, it’s also important that they equip their workforce with the right skills for the challenges ahead.”
Average output growth rates regionally remain varied, with areas like the South-west (2.8 per cent) and North-west (2.2 per cent) expected to record growth over the next five years.
However, Scotland (-0.6 per cent), the North-east (-0.1 per cent) and the East Midlands (-0.2 per cent) are all expected to contract.
The biggest shift was in London, where the growth forecast for the next five years has fallen two percentage points to 1.5 per cent, down from 3.5 per cent in January.
As a result only 25,350 new workers will be needed every year in England, compared with 34,950 in January.
Meanwhile 3,540 workers will be needed in Wales (down from 5,440), 1,810 will be needed in Scotland (down from 4,270) and 650 will be needed in Northern Ireland (down from 1,760).
The CITB said infrastructure projects such as Hinkley Point C have boosted its growth forecast.
But it added that the infrastructure sector was still likely to contract more than previously thought due to pauses in road building and weak performance in the electricity sub-sector.
The commercial sector is likely to be the hardest hit by the EU referendum, with output over the next five years now expected to grow by 1 per cent by 2020, rather than 3.4 per cent.
Growth in the repair and maintenance sector has also been revised to 0.7 per cent, down from 1.2 per cent.
“Our new figures reflect the increased uncertainty in a Brexit-facing world.
“While construction’s slowdown cannot be solely attributed to the result of the vote, it has certainly intensified and hastened any decline in growth.”
He added: “While on the whole the outlook has worsened, we do need to keep some perspective.
“The economy is bearing up reasonably well in the wake of the uncertainty and construction has a healthy programme of major projects and infrastructure works in the pipeline.
“Projects such as Hinkley, Wylfa and HS2 will undoubtedly buoy up the sector in the medium term.
“However, delays and uncertainty over investment decisions and access to migrant labour will likely intensify as Brexit nears.”