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Two of New Zealand's newest shopping malls and the Waitakere stadium hosting tonight's world netball final have been caught out by faulty engineering design work that new regulations have so far failed to curb.
Westfield has confirmed that initial engineering designs for its $210 million Albany Mall - New Zealand's biggest - and the expansion of the Chartwell Mall in Hamilton had to be changed after peer reviews.
Auckland's $80 million Vector Arena, a Christchurch commercial building and an Auckland multi-storey building that includes apartments have all had to be repaired after faults appeared during construction because of poor engineering designs.
Engineers say some other new buildings, where faults were not picked up, will be at risk of collapsing in a big earthquake because of widespread unsafe practices such as repeated bending of steel bars in reinforced concrete, inadequate anchoring of spiral reinforcing, and the use of brittle imported steel which is not made for New Zealand's high earthquake risks.
An original design for Waitakere's $27 million Trusts Stadium, which is hosting the world netball championships, had to be referred to the Heavy Engineering Research Association (HERA) after a problem arose.
Canam Construction director Nick Page, who managed the construction, said "some minor detailing changes" were made.
"Like any job, there was some work done after it was erected, but there was no failure or anything. There was work done. It was straightened out," he said.
HERA structural engineer Dr Charles Clifton said: "The system worked. The problem was identified and fixed."
But critics say a new licensed building practitioner scheme, which came into force from November 1, will not be enough to tackle the poor design work and unsafe building practices.
Auckland structural engineer John Scarry, who wrote an open letter to the engineering profession about industry practices in 2002, says standards have got worse in the five years since then.
A former president of the Structural Engineering Society, Dr Barry Davidson, says cost-cutting by engineers competing for both design contracts for developers and review work for local bodies is resulting in unsafe buildings.
"The real problem is that the developers' job is to make money," he said.
"Therefore they get a design fee from the cheapest structural engineer, and on top of that the structural engineer gives the cheapest design.
"The thing that really concerns me is: is the design safe, and has it been adequately checked? I think the answer to both questions is often 'no'."
Charles Black of Reid Construction Systems, which makes a threaded insert to avoid the need to bend reinforcing steel, estimates that 65 per cent of the 80,000 precast concrete panels installed in New Zealand every year use protruding steel starter bars that are commonly bent to be transported to a building site by truck and then bent back into shape on site - even though this breaches industry guidelines.
"They are building buildings all over Auckland and not getting the reinforcing treated properly," he said.
"If we have an earthquake there is the potential to have hundreds of people squashed."
Westfield NZ deputy director Justin Lynch said the financial liability for design changes required on the Chartwell Mall was still subject to dispute.
"Westfield Chartwell did experience some delays in its construction schedule," he said.
"The question of financial impact is a matter currently before all parties for determination, with a due process to be followed. For this reason we would prefer not to discuss the question of legal action at this time.
"At Westfield Albany, the peer review process also resulted in some design change recommendations, which Westfield carried out to the satisfaction of both council and independent reviewers.
"We are confident that both our Chartwell and Albany buildings fully adhere to all industry requirements, as indeed do all our New Zealand buildings, and that our buildings are safe."
Cutbacks affect sprinklers
Up to 160 buildings around the country may be at risk of fire because water authorities have reduced water pressures to such low levels that sprinkler systems will no longer be effective.
The fire protection industry says sprinkler systems are being effectively immobilised by ageing pipes, expanding cities and efforts to cut water wastage, which have combined to lower water pressures in many areas.
Tim O'Brien of VeriFire, the country's main sprinkler certification company, says a new model bylaw for water supply, adopted this year by Standards NZ, has made things worse by stating that water authorities "cannot guarantee an uninterrupted or consistent supply of water".
Auckland fire engineer Tony Gibson says Standards NZ has been "captured" by vested interests that can afford to sit on its committees, such as water authorities.
The Fire Protection Association, which represents mostly smaller fire alarm and sprinkler companies, was not told about the proposed model bylaw until a week before it was due to be finalised.
"This is leaky buildings all over again," Mr Gibson said.
The sprinkler problem affects fewer buildings - only about 8000 buildings, apart from domestic homes, have sprinkler systems, and Ron Green of Fire Security Services estimates that so far water pressure has fallen below design levels for up to 2 per cent of them, or 160 buildings.
But the buildings with sprinklers affect many thousands of peoplein factories, offices, apartmentblocks, hospitals, schools and rest homes.
And Mr O'Brien says the number affected is likely to increase as water authorities struggle to serve growing populations with ageing pipelines springing ever-increasing leaks.
So far only pockets of the country have been affected enough to make sprinklers ineffective.
