The Education Ministry is clearing out its quake-prone head office, at the same time as some schools are still using their quake-prone buildings.
The Ministry of Education's building in Bowen Street in Wellington. Photo:
A new seismic assessment has scored the Wellington office block, with room for 1000 workers, at just 25 percent of New Building Standard.
Ministry workers have till Monday to vacate.
But schools have for years been using and are still using 29 buildings that are rated earthquake prone, or under 34 percent. One of those is partially occupied.
There are six other quake prone ones not in use.
The ministry said it took a "consistent" approach to decisions around both corporate and school buildings.
Its engineering strategy group along with experienced earthquake engineers, reviewed assessments and advised on continuing to occupy a building, leader of Infrastructure-Hautū and Digital Scott Evans said.
"These recommendations are based on the nature of the engineering risk and an assessment of the practical steps that can be taken to eliminate or minimise the risks."
RNZ has asked how many of the 29 buildings are in a high-risk quake zone.
Minimising risk to students and staff went in hand with supporting daily operations "with minimal disruption", until a long-term plan could be developed, Evans said.
The ministry took swift action at its head office based on a partial seismic assessment targeted at the floors.
Listen to today's Morning Report interview with structural engineer John Scarry
Floors have provoked confusion, because there are two sets of guidelines in play - and while the newer 2018 rules are superior, the older 2017 rules are those with legal standing. The newer ones will, typically, score a building lower than the older guidelines, if it has hollowcore precast concrete floors.
Engineers called last year for officials to clear up the mess.
The ministry's engineers appear to have used the 2018 rules to arrive at the 25 percent rating.
Stuff quoted the building's landlord saying the ministry move was a kneejerk reaction in response to the guideline shifts.
The ministry said decisions on risks to core structural strength, such as at its head office, are looked at differently from non-core problems, such as with cladding (though it can fall off in an earthquake).
"This approach aligns with the Building (Earthquake-prone Buildings) Amendment Act 2016, the Health and Safety at Work Act 2015 and is consistent with the 2018 WorkSafe guidance that confirms that a low seismic rating does not necessarily mean the building should be vacated."
Last year the ministry admitted it had not been tracking how many schools had been fixed, so they were no longer rated as earthquake-risk (a technical category that covers buildings rated 34-67 percent NBS, with sub-34 percent being quake-prone).
This was despite this being a stated medium-term goal is to strengthen all school buildings to 67 percent NBS as far as practicable.
When the ministry first went looking a few years ago, it found 130 school buildings were under 34 percent NBS.
The ministry said of the quake-prone school buildings still in use, 12 were in a high-risk seismic zone, six in medium-risk and 10 in low-risk zones.
Of the 12 in the high-risk seismic zone, 10 were one or two storey buildings with a lower risk profile, while two were more than two storeys, with their quake-proneness due to secondary elements such as cladding, rather than structural elements .