Fletcher Building is closing its loss-making copper tube factory in Sydney, with the loss of 108 jobs.
The infrastructure and building materials manufacturer will close its Crane Copper Tube factory in Penrith, in Sydney's west.
Manufacturing at the factory is due to end in December, with exports from the plant expected to wind up within 18 months.
Fletcher said the business had been unprofitable for several years, partly because of overcapacity in the market for copper tubing used in plumbing work.
Many copper tubes were also being substituted by plastic products, and there had been increased competition from overseas suppliers.
Chief executive Mark Adamson said the decision to close the factory was made after a range of options to help restore it to profitability were considered.
"I realise this is a particularly difficult time for our employees and we are committed to ensuring any potential opportunities for redeployment within Fletcher Building are fully explored," he said on Wednesday.
"Where that is not feasible, we will support our employees through the transition to alternative employment."
The decision to close the factory is expected to cost Fletcher, which is listed in New Zealand and Australia, about $NZ19 million ($A17.69 million).
Crane Copper Tube has operated since 1959. It makes a wide range of plumbing, refrigeration, airconditioning and medical gas tubes for sale in Australia and overseas.
