Overseas construction workers on 457 visas had to live in the office and sleep on the floor after wages dried up, a union says.
The Australian Manufacturing Workers Union says 12 workers brought to Australia by Schneider Elevators Australasia had been working on a Victorian building site.
"When their pay suddenly stopped six weeks ago, (they) had nowhere to live, no shelter except sharing the floor of their employer's office," AMWU assistant Victorian secretary Craig Kelly said on Friday.
Mr Kelly said the 457 visa program cruelly preyed on the hopes of overseas workers.
"These workers were brought in on a promise of lucrative wages to send back to their families but find themselves exploited, paid well below local industry standards," he said.
"The company clearly knew there was an issue, as they allowed the workers to sleep in the office, and even cook food in a kitchenette."
Mr Kelly said the company owed the 11 Filipino and one British worker more than $172,000.
He said Schneider Elevators also deducted visa charges and "building industry fees" from their wages.
Mr Kelly said five Australian employees had also been denied wages.