Weak, sub-standard, faulty Firth concrete has now been discovered in the University of Auckland's $200 million city campus science redevelopment and expansion.

Peter Fehl, the university's property services director, announced that part of the new 11-level 23,500sq m block would now have to be demolished.

"The areas in question are a small basement wall and a portion of level 11 floor slab," said Fehl who is in charge of the major changes to the science faculty, headquartered on the corner of Wellesley St and Symonds St and the site of New Zealand's biggest tower crane.

Yesterday, Fletcher Building announced Firth had stopped production at an Auckland plant following a quality control testing programme which found some concrete had not met product specifications.

Andrew Moss, Firth general manager, said: "Firth will do the right thing by its customers and replace the concrete where necessary as promptly and efficiently as possible."

Fehl said the university was now working with Firth to rectify matters on the science building.

"Firth are carrying out tests to determine the full extent of the problem and it is likely that the basement wall and a portion of the eleventh floor slab will have to be replaced. The impact on the programme is as yet unknown," Fehl said.

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