Unions are concerned jobs will be lost at Fletcher Building after it decided to stop bidding for new work constructing commercial high rise towers and public buildings.
The country's biggest construction firm announced the move by its buildings and interiors division this week as it deals with an expected $660 million in losses.
The division would now focus on finishing a pipeline of 73 existing projects that were 65 per cent complete, with the last project due to be finished by mid-2019, the company said.
However, E tu coordinator for construction Ron Angel says the troubles at the building giant threatened to leave 120 union members without jobs.
"We're trying to find out what happens next, but we will have members affected by this - though it's currently unclear how many," he said.
He said union members in Christchurch had been told to expect closures once work was finished on company projects in the city, including the Justice and Emergency Services Precinct.
Some workers would be entitled to redundancies and others wouldn't, while it was hoped others could be redeployed to different Fletcher divisions, Mr Angel said.
In a statement to NZ Newswire, Fletcher said it was focused on "identifying new opportunities" for its workers.
It said as it completed its pipeline of business and interiors projects, it would look to re-deploy workers to other projects, either in the same division or in other divisions of the company.
"We are currently working through the detail of this transition process and will keep our people updated as we progress," the company said.
It said its decision to stop bidding for new work only affected its business and interiors division, which builds commercial and public buildings.
Fletcher's three remaining construction businesses, Infrastructure, Higgins and South Pacific, would still bid for new work, the company said.
Infrastructure and Higgins manage large scale infrastructure projects, such as roading, public transport and public works.
A separate Fletcher Building business, called Fletcher Living, handles residential construction and would also still be bidding for new work.
E tu's Mr Angel, meanwhile, criticised Fletcher over its Christchurch justice precinct building work, saying there had been a lack of supervision and experience in project management.
"Our members have told us that 50 per cent of that project was built twice," he said.
"The workers say they'd put stuff up and a week later they'd be pulling it down again because the design changed or there were design faults, cracked tiles and the like."