Local authority construction workers join biggest national strike since 1926.
About 70,000 construction workers have joined a national strike of 1.5 million council workers over pensions.
The workers, employed by local authorities, are represented by UCATT, Amicus, TGWU and the GMB. The strike began at midnight and is scheduled to last for 24 hours.
The dispute, Britain's biggest industrial walkout since 1926, centres on the government's attempts to remove the so-called "85-year-rule" from October. The rule allows workers to retire at 60 on a full pension if their age and years of service total 85. The government wants to raise this age to 65.
Alan Ritchie, UCATT general secretary, said: "It is clear to everyone, be it Sandy Bruce-Lockheart the Tory Chair of the Local Government Association or John Prescott himself that low paid government workers have had enough of being treated as second-class citizens. Well let me tell them now and in the strongest terms possible, local government workers are the heartbeat of our public services, they are not second-class citizens and should not be taken for granted."