The Employment Relations Authority has found Christopher Wright was unjustifiably dismissed by Christchurch company Maiden Construction.
In its determination decision, the authority said Wright was hired for a 14-week project in Blenheim in early 2020.
But when he returned to Christchurch after the first week, his employer asked to meet with him and Wright was told he was about to be sacked, though no reason for this was given.
Maiden Group director Murray James conceded that Wright was dismissed in circumstances where the company wrongly believed he was the subject of a 90-day trial provision - but this was not detailed in his contract, the authority said.
However, James said Wright did not fit in with his co-workers and there had been complaints about him from the foreman.