The Unite union says that approximately 100 of its construction members will be demonstrating outside Balfour Beatty’s Newcastle University building site between 6.30am and 8am on Wednesday 21 September.
At the same time, a similar number will stage a demonstration at Farringdon station in London, where Crown House is working.
Demonstrators will also be out in force between 10am and 11am at MediaCityUK in Salford Quays, where NG Bailey and Crown House Technologies are on site.
Unite says that its members face pay cuts of up to 30% because of employers are tearing up long held national agreements in the M&E sector.
The eight contractors involved are: Balfour Beatty Engineering Services Limited; NG Bailey Building Services; Crown House Technologies; Gratte Brothers; MJN Colston; Spie Matthew Hall; Shepherd Engineering Services (SES); and T Clarke.
Unite regional officer Steve Benson said: “Our members are furious about this attack by these so-called reputable companies aimed at reducing our members’ income by up to a third.
“The companies are trying to bulldoze their plans through by ripping long-standing national agreements without any negotiation.
“These rogue employers should pull back from the brink as their brutal onslaught on workers’ skills, pay, and terms and conditions is causing widespread anger among workers.”
Five of the eight breakaway companies - Balfour Beatty, Crown House, Spie Matthew Hall, SES and NG Bailey - have issued formal notice to workers that they will be sacked if they do not sign new contracts by 7 December.