Police are investigating a suspicious fire at Fitzroy School in New Plymouth, over the weekend.
Fire crews found a wall alight just after 4am on Saturday, New Plymouth senior station officer Ian Drewery said.
Firefighters quickly had the blaze under control but a deck area had suffered damage.
"It's in the hands of police at this point," he said.
School principal John Mansfield spent most of Saturday at the school with insurance assessors and builders.
The fire had damaged an outside wall of two classrooms, and burned holes in the roof of a deck, Mr Mansfield said.
"Thank god it didn't get inside," he said. "It wasn't far away from taking hold."
Mr Mansfield said builders had boarded up the damaged area on Saturday and the classrooms would be in use today.
"It's business as usual, despite the smoky smell."
He described the suspicious fire as "extremely disappointing" but said he was relieved that it did not cause any more damage.
"We are so lucky. We have two new classrooms that are not far away from where the fire was, so I'm glad it didn't reach them," he said.
Mr Mansfield said he would be talking with people from the Ministry of Education about the blaze today. He believed insurance would cover the costs of the repairs.
- Taranaki Daily News
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