The Christchurch firm that designed the ill-fated CTV office block which collapsed in the February 22 earthquake, killing 115 people, may have built similar buildings that the council does not know about and have since gone unchecked, officials admitted today.
Christchurch City Council staff and Mayor Bob Parker fronted media over the royal commission report into the CTV disaster for the first time this afternoon.
They said buildings built in similar fashion to the CTV building have since been reviewed and building owners contacted.
Meanwhile, they have also taken a close look at other buildings built between 1980 and 1990 by Dr Alan Reay, whose firm Alan Reay Consultants Ltd designed the six-storey Christchurch structure that came down in the magnitude-6.3 quake.
Dr Reay was slated in the royal commission report for giving his inexperienced structural engineer David Harding "sole responsibility" of coming up with its design in 1986.
He is also fingered for not reviewing Mr Harding's final plans, and for playing a part in the city council wrongfully signing off a building permit.
The CTV building was the only building in Christchurch to totally collapse in the violent shaking.
Steve McCarthy, the council's environmental policy and approvals manager, confirmed that the "six or seven" multi-storey buildings designed by Dr Reay's firm during the eighties have been checked.
But he accepted there might be more that he does not know about.
"We don't know all of Alan Reay's buildings, but we've certainly checked the ones which were identified in the royal commission," Mr McCarthy said.
"A lot of them are no longer here - they've been demolished."
He accepted that some of Dr Reay's buildings may have gone unchecked, but he said the council was not "targeting Alan Reay buildings as such.
"We're treating his buildings the same as every other building," he said.
The council was criticised in the report for wrongfully signing off the building's faulty design in 1986 and for council officials "green-stickering" it after the first major earthquake in September 2010, with no expert advice from an engineer.
While council officials accepted the building did not comply with the local bylaw code of the day, they said today that the rules and regulations around building consents have changed "significantly" since then.
National building legislation now requires the council to be regularly audited, and there are now systems in place to ensure high-risk buildings are signed off by qualified engineers.
Mayor Parker apologised for the council signing off the building, and said today's council accepted responsibility for its part in allowing such a flawed building to gain a permit.
Everyone at the council was "truly sorry", he said, but added that the situation needed to be put into its historic context.
The council says it has taken the commission's findings "very seriously" and will take more time to consider its 83 recommendations.
Kelvin Reid, barrister and legal advisor to the council, said the council was not currently preparing itself to respond to any legal action against it.
But the council would "absolutely" cooperate with any police investigation, Mr Parker said.
"If there should be any consequences of that, then so be it.
"The police will decide, initially, where that final legal responsibility rests, and I dare say there is the potential for others outside of that to take actions."