Local councils are being asked to sign off on major buildings when they have big gaps in what they know about the steel frames and seismic strength.
That's according to Steel Construction New Zealand (SCNZ), an industry body that has been briefing councils about the dangers of having an inadequate building consent regime.
SCNZ had been fielding a growing number of calls for help, from engineers and building owners but also from councils, its chairperson Wayne Carson said.
"They are realising now what they need to know - they didn't know what they didn't know," he said.
"I liken this to the leaky building syndrome ... councils have certainly realised that there's great similarities with compliance as there is with leaky buildings."
Mr Carson, who works for large Auckland fabricator D&H Steel, led recent SCNZ roadshows to councils in Wellington, Tauranga, Hamilton, and Christchurch, and all councils south of Dunedin.
"The traditional kind of procurement process meant that councils would, at the end of a project, be delivered a whole lot of documentation to say, 'here we go, we're finished' and then be expected to sign it off.
"And, in some cases, that has been the point where the alarm bells have gone and so they're - in retrospect - trying to deal with some of these issues."
Like the councils, many consulting engineers had not known how to ensure there was a system of rigorous checks on whether the raw steel and welding were up to New Zealand standards and seismic standards.
The problems centred on mid-range commercial buildings rather than really major projects, or the likes of the Christchurch rebuild where scrutiny had in general been better.
"There's been two or three buildings we're aware of where councils have come for advice, knowing in retrospect that there are some concerns around meeting Building Standards demonstrating compliance."
The trouble-plagued Alexandra Park Village development at the trotting club in Epsom was one of these, though this was close to being fixed, Mr Carson said.
The Auckland Trotting Club declined to comment.
In Auckland, the council was asking many more questions about steel than it did when it consented the Epsom project.
It has had no choice but to develop more rigourous checks, said Andrew Minturn, the council's meeting demand programme manager.
"We have some extremely challenging and high-rise buildings and, being new technology, we want to make sure that we have done everything within the regulatory framework that gives us confidence that the steel that is being used - both from a manufactured and from a fabrication perspective - is of a quality that from a New Zealand standard, we would accept in that construction," Mr Minturn said.
The Auckland Council co-led the SCNZ roadshow, and was sharing its steel compliance checking system with other councils.
One lesson is that independent or third party oversight is crucial.
"We're not necessarily saying straight away that we don't agree that the steel being used was inappropriate," Mr Minturn said.
"What we are doing is we're satisfying ourselves - as is a regulator's right - that the information being provided by these third parties is up to scratch."
However, some other councils have been relying on a consulting engineer - who is hired by the main contractor - to vouch for the steel and the quality controls around it.
SCNZ's Wayne Carson has been telling councils this was absolutely not good enough.
"There was a general lack of knowledge," he said.
"Many of these councils, we find, they're limited in resources. They have been relying on a lot of external advice.
"[But] there's a lot of engineers that also lack knowledge in some of the detailed compliance issues."
The roadshow gave councils the right questions to ask early on, Mr Carson said.
"It doesn't mean you know the answers, but you need to ask the right questions to flush that out".
Steel compliance was undergoing rapid, big improvements compared with five years ago, he said.
Mr Minturn of the Auckland Council agreed.
"The other councils which have participated, are seeing more steel and they are very open to the material the Auckland Council is developing.
"Yes, it may be a case of we didn't know. We're on a very fast learning curve."
SCNZ was planning to brief other councils about compliance.