A redevelopment of Clayton Park School in Auckland is to cost $14.5 million.
The primary school in southwest Manurewa has old and leaky buildings and issues with asbestos.
Associate Education Minister Nikki Kaye announced on Sunday the funding for a redevelopment.
"I am pleased that the redevelopment will see most of the school's existing buildings replaced. This solution will add 19 permanent teaching spaces but retain the recently built hall and administration areas," she said.
Temporary classrooms will remain in place during the redevelopment, expected to take two years, and will be removed when it's completed.
Construction is due to start later this year.
The school has a history of positive Education Review Office reports.