UCATT members at HTC Plant Limited have overwhelmingly voted for strike action following a dispute over pay.
With a turnout of more than 80%, 94% of the 180-plus crane drivers taking part in the vote were in favour of strike action and 94.6% voted in favour of industrial action short of strike action.
UCATT is now in consultation with its activists at the company, with plans to announce the dates and nature of the industrial action by the end of the week.
UCATT general secretary Steve Murphy said: “This result is so emphatic that there is no doubt that within days, key construction sites will grind to a halt.”
Sites that will be affected include Crossrail, the London Bridge redevelopment, Nova Square Victoria, the Elephant and Castle redevelopment and the Atomic Weapons Establishment at Aldermarston.
Major contractors who will be affected by the industrial action include Kier, Lend Lease, Bam, Costain, Mace and Vinci.
Since 2008, crane drivers at HTC have experienced several pay freezes and have seen their pay plummet in real terms.
UCATT had entered negotiations with the company, which failed to table an offer close to UCATT members’ expectations.
Mr Murphy added: “HTC needs to understand that crane drivers believe they deserve a decent pay rise and are prepared to fight to win one. The only people who can prevent construction chaos is HTC.”
Since announcing the ballot for industrial action, UCATT has seen a rise in membership among crane drivers.