Market-related pay structures and lower levels of union recognition among registered social landlords have combined to make the problem worse, the union says.
Unison is in talks with a London-based RSL about introducing a job evaluation system, under which different roles can be compared for the purpose of setting pay, to ensure it complies with the 1970 Equal Pay Act.
Under that law, women are entitled to equal pay unless there is a genuine reason, unrelated to gender, for being paid less.
The union estimates that up to 30 of the RSL's employees may have been underpaid.
If these cases went to an employment tribunal, it could cost the RSL up to £600,000 in backdated pay.
Colin Meech, Unison's national housing officer, said: "Equal pay is our number-one bargaining priority. Research has found that women's pay still lags behind men's, and 70% of Unison's membership is female.
"We believe housing associations are being left behind. They've been slow at developing job evaluation systems and more set their pay levels in relation to the market."
Meech said Unison would be looking closely at group RSLs with care home subsidiaries.
"A female care worker will often be paid less than a male caretaker, despite the fact that under job evaluation systems those jobs are broadly similar," said Meech.
James Tickell, deputy chief executive of the National Housing Federation, said: "Housing associations aim to be good employers and should have nothing to fear from scrutiny. We're a major sector and while I can't say everyone will have got things right, I'd be astonished if there were many instances of non-compliance with the law."
Unison's move follows the introduction in December of a new code of practice on equal pay by the Equal Opportunities Commission.
The code states that organisations that do not have a job evaluation system will have no defence if a case is taken to an industrial tribunal.
Source
Housing Today
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