Ministry won’t name all 30 sites, but English says total in need of repair closer to 60.
A list of the country's most leaky and mouldy schools is being kept secret by the Government because it doesn't want Crown ministers pressured to make decisions.
About 30 schools were identified as needing major redevelopments in 2013, the Government assigning $300 million for rebuilds and renovations.
But this month, Finance Minister Bill English revealed the schooling network was "in worse shape than we thought" and there were probably more like 60 schools needing extensive redevelopment.
Common issues have included leaky buildings that are draughty, mouldy and damp. Some schools have problems with rats. Others have been air tested and have closed classrooms because of high spore counts, which can be hazardous.
The Herald asked the Ministry of Education for a list of those schools needing major redevelopment.
It was given the names of just 16 schools - those already publicly approved. The rest of the list was declined, with the head of the infrastructure service Kim Shannon saying their redevelopments were "by no means guaranteed".
"The list may change due to budget constraints and due to the possibility that other schools may be identified as higher priority once condition assessment work is completed."
The request was declined under section 9(2)(i) of the Official Information Act "so as not to prejudice the decisions of minister and/or Cabinet decision-making process".
That section applies only if withholding the information is necessary for a minister of the Crown or department to carry out commercial activities without disadvantage.
Associate Education Minister Nikki Kaye supported the decision, saying time must be allowed to consult with the school and community and consider the available options.
However, Clayton Park Primary School principal Paul Wright, who has closed classrooms with high spore counts, says the information should be made available to the community.
"It's their children," he said. "We have a democracy. The Official Information Act is there to ensure the public have access to information ... it's a tool we use as a school and it should be respected."
Mr Wright believed the Government didn't have the money to fix all the schools and didn't want to publish the names of those in need as those communities would apply pressure.
Green MP Catherine Delahunty, who has also tried to find out which schools had rebuilds delayed, said the refusal to name affected schools was an attempt to "keep a lid" on the issue.
"Actually, the job is just to fix all the schools that need fixing. They need to come clean over this."
• In 2013 the Government identified 30 schools nationwide requiring extensive redevelopment for issues like mould, leaks and general dilapidation.
• $300m was set aside.
• But the situation is worse than anticipated, and Finance Minister Bill English says the schools with serious problems may number 60.
• Air testing is under way to ensure schools are safe - some classrooms have been closed.
• The Ministry of Education is refusing to say which schools require major work.
The Ombudsman is considering a complaint about the refusal.