Asian steel may not meet NZ standards

Asian-made steel being used in construction here could weaken buildings' resistance to earthquakes, local industry chiefs have warned.

Fletcher Building chief executive Ralph Waters says not all steel being used here meets New Zealand's earthquake risk standards.

He has backed a Government report which revealed problems with steel and warned about the need to check sources of the product.

Waters said buildings were not necessarily at risk of collapsing but said steel which met New Zealand standards was tougher than cheaper steel produced overseas being used on buildings here.

"This is an earthquake zone and there's a standard here that we build our steel to that's more comprehensive and tougher than is necessary in many other places around the world," Waters said.

"People bring steel in that doesn't meet those standards but is cheaper and it gets used, so who's going to know when it's buried in a concrete column? But it doesn't necessarily mean things are going to fall down," he said.

Fletcher was producing steel with a stamped imprint to identify its products, he said, which met New Zealand standards.

But Roshan Nauhria, owner of Nauhria Building Supplies in East Tamaki, said his company brought in about 8000 tonnes of reinforcing steel from Singapore annually and said it complied with the New Zealand standards. Pacific Steel was attempting to raise concerns because it was losing a certain share of the market, he said.

Alan Pearson, Pacific Steel's general manager, said a Department of Building and Housing report - published in August - highlighted the issues within the industry. The department has told the building and construction industry to organise education programmes to ensure one grade of reinforcing steel - 500E - was used correctly, Pearson said.

"We continue to be concerned about the quality of imported steel, as independent tests performed by SGS New Zealand found that bars from all of the three sources of imported product failed to fully comply with the New Zealand standard," Pearson said.

In the report Dr Barry Davidson of the University of Auckland and the Structural Engineering Society raised concerns that some steel reinforcing might not be fit for its purpose when it was tested in earthquake conditions in reinforced concrete structures.

There were also reports of bars breaking when handled on site, the department reported.

Structural engineer John Scarry also mentioned concerns about the bending and re-bending of reinforcing steel in his report issued three years ago on the industry, it said.

The department investigated the concerns and asked Association of Consulting Engineer members to report any problems with steel.

It also commissioned a report from Beca Consultants on the compatibility of the various standards covering the manufacture, design, welding and handling of reinforcing steel. 

Hard facts

* New Zealand uses 100,000 tonnes of reinforcing steel annually.

* Steel sells for around $900 a tonne so the industry is worth $90 million.

* Pacific Steel supplies about 80,000 tonnes annually.

* The remainder is imported from Singapore, Malaysia and Thailand.

* Steel reinforcing is used on bridges, dams, wharves and in high-rises.