Structural engineers are concerned low quality steel is coming into the New Zealand market and are calling for more quality controls on imported materials.
However, the Minister of Building and Construction, says there is often little to back those claims up and describes much of it as hearsay.
One of New Zealand's leading steel engineers, Charles Clifton, says before the 1980s, most steel was made in New Zealand and Australia and it was consistently of good quality.
He estimates up to 80% of structural steel is now imported and says it's harder to ensure imported steel is at required specifications. He says below par material has made it into the market here.
Building and Construction Minister Maurice Williamson says the quality of imported steel is often queried but those doing so don't usually have specific examples that can be investigated.
He says many complaints come from manufacturing companies trying to bring down the reputation of a rival.