More than 170 housing maintenance staff working for Mears are to begin all-out strike action in Manchester this week.
Union Unite have announced a continuous strike will take place for four weeks from 08 July to 04 August.
The latest escalation comes as workers enter their 18th day of industrial action in a dispute over pay differentials, as well as changes to terms and conditions.
Mears is seeking to introduce a new contract which increases hours, introduces flexible working and requires the greater use of technology. In addition, the company is looking to introduce a 'productivity procedure' (describe as a 'sackers charter' by Unite) and is pressurising the workforce to accept poorer conditions regarding sick pay and vehicle policies.
Other issues leading to industrial action included pay differentials, which results in workers being paid up to £3,500 less than colleagues for undertaking the same work.
Unite said the decision to escalate the strike follows a refusal by Mears to find a negotiated settlement through talks to the dispute.
Unite said: "Instead the company has sought to undermine the ongoing action, by requiring staff to work on weekends, which is not part of their normal working week. Younger workers have also been directly targeted and bullied by management into breaking the strike."
The union's regional co-ordinating officer Andy Fisher said: "Unite is stepping up its strike action in response to Mears' failure to enter into negotiations to resolve the dispute and is a direct consequence of the company's attempts to undermine our industrial action.
"Inevitably the escalation in action is going to have serious consequences for tenants; while this will lead to a delay in repairs and maintenance work I hope that they recognise that this is entirely the making of Mears.
"Our members have only taken industrial action as a last resort. Mears has had years to resolve this issue and end the inequality and injustice faced by our members but has failed to do so."
(LM)
UK
Ireland
Scotland
London











