Increased tests on steel mesh emphasise 'ductility' to ensure quake buffer

The government has set out how steel mesh must be independently tested to ensure ductility, or the steel's ability to stretch as it should in an earthquake.

Building and Housing Minister Nick Smith said the steel product would need to be tested across more samples, using "internationally accredited testing laboratories." Smith downplayed the scale of issues with substandard steel mesh, saying the Commerce Commission "is investigating issues with the quality of a small amount of steel mesh."

Steel & Tube Holdings, one of the manufacturers being targeted by a Commerce Commission investigation, has given the commission an undertaking that it will only sell mesh that has passed independent testing. The commission continues to investigate whether Steel & Tube breached the Fair Trading Act by producing testing certificates which included the logo of a laboratory which did not undertake the testing or by making misleading or unsubstantiated representations that the steel it supplied complied with the standard.

Steel & Tube cut its guidance in May.

The updated Verification Method and Acceptable Solution will apply to grade 500E steel mesh sold in New Zealand under changes that will start on May 30, 2017, Dr Smith said in a statement. "We're increasing the number of samples which need to be tested, clarifying how that testing is done and requiring testing be done by internationally accredited testing laboratories," he said.

Steel mesh used in residential buildings is required to have 10% ductility under tighter rules brought in after the Canterbury earthquakes.

"We're in the midst of a building boom and we need to ensure quality is maintained by making sure our materials match the required standards," Dr Smith said.

The commission is also investigating whether Brilliance Steel Ltd sold steel mesh in breach of the Fair Trading Act.

In March 2016, the Commission issued a Stop Now letter, requesting that Brilliance stop selling steel mesh until the Commission’s concerns were addressed. Brilliance complied with that request. The commission’s investigation continues. 

* This story has been updated to include the last two paragraphs.

(BusinessDesk)