Further information has been released on the parlous state of Greater Wellington Regional Council's quake-prone former central city head office.
The yellow-stickered building is now empty after the last of the council's 270 staff finally shifted into Shed 39 - a newly strengthened and retrofitted two-storey Centreport building formerly leased by TelstraClear.
Council chief executive David Benham said staff were pleased to finally get into offices that were now seismically rated at 90 per cent of new building standard.
He said a decision would likely be made next year on the future of the old Wakefield St head office building.
Strengthening it to 40 per cent of new building standard was estimated to cost $7-8 million and another option would be to sell it "as is, where is", said Mr Benham.
The building, which sustained some damage in the magnitude 6.5 July 21 quake, had been rated a high risk by Spencer Holmes engineering consultancy.
It was built on land with a high potential for liquefaction which its foundations were not designed for, the piles were lightly reinforced, shear walls were brittle and its concrete flooring was liable to fail in a major quake.
The 10-storey tower and its five-storey annex were also likely to pound against each other.
However, further problems were found after the July quake when five floors were flooded by a burst water pipe.
Spencer Holmes reported that minor cracking had been found in shear walls and it recommended the main stairs should no longer be used as they found inadequate reinforcing of a concrete nib supporting the precast scissor stairs.
"The defect is sufficiently significant that we consider the main stairs may be compromised in a moderate to major quake."
Mr Benham said staff were relieved to be in safer accommodation, a place where they could be sure to be up and running again after a major quake.
Shed 39 was costing the council $1.2 million a year in rent, which was comparable to the cost of their old building.
It had a six year on the Centreport building although this could be terminated after three years if it was no longer needed with Wellington's proposed local body reform.
- © Fairfax NZ News
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