More than 40 school cleaners in six schools in Hackney, east London, have voted to strike by 100 percent on a 60 percent turnout.
The members of the Unite union are planning to walk out from Tuesday 30 January to Friday 2 February and again on Monday 5 February.
They are employed by OCS Group, which, Unite says, is refusing to update its pay rates to reflect the new level of the London Living Wage (LLW).
Bosses are also proposing to cut pay with new term time only contracts, and refusing to pay holiday pay in line with inflation.
Unite regional officer Onay Kasab called it “outrageous salami-slicing by OCS of pay and employment conditions of an already low-paid group of workers.
“Our members have voted overwhelmingly to stand up to OCS, which is a very poor example of the privatised contracting-out culture.
“OCS continues to blatantly ignore the requirement of Hackney council that its contractors pay the LLW.
“It has also refused to pay proper holiday pay, despite the recent holiday pay/overtime court ruling on this subject.
“The bosses need to sit down and hold constructive talks with Unite to resolve this dispute.
“Otherwise classroom rubbish will be uncollected and toilets uncleaned at the end of January with further action on the cards going into the spring.”
Schools that will be affected by the strikes include Cardinal Pole School, Clapton Girls Academy, Urswick School, Haggerston School, Ickburgh School and Stoke Newington School. Teachers should support them.