A lack of regulation in the cleaning industry has some contractors earning less than minimum wage

A new Workforce Development Council report finds the number of cleaning businesses has jumped 63 percent since 2014.

Many are owner-operators.

Building Service Contractors chief executive Sarah McBride says economic pressures have people cutting costs out of their cleaning contracts - but labour makes up 85 percent of them.

She says the concern is people are buying commercial cleaning contracts for 30 to 40 percent lower than those from cleaning contractors that directly employ their cleaners.