The fire happened around 2:30 Monday afternoon inside the chapel of the school, located off of Route 13.
Fire crews were able to quickly get the fire under control. However, during the battle, twelve expensive stained-glass windows were broken.
Fire officials say roofers were working on the roof when the blaze broke out. A torch being used to spread asphalt on the roof is blamed for starting the fire.
A volunteer firefighter sustained a minor injury while battling the blaze, otherwise there were no injuries reported.
Classes were not in session at the time of the fire.
The fire struck just as the school was preparing to celebrate an important milestone. For the better part of the past year, Father Jeff Duaime was focused on this church's past. Dedicated in 1910, it was about to enter is centennial year.
Now, a day after the fire struck, he's instead focused on its future.
"As a Catholic School, it is very much at the center of our prayer life and of our faith," said Father Duaime.
Early estimates put the costs for repair at more than a million dollars, much of which will be covered by insurance.
"I wonder whether it'll be enough because the stained glassed windows that were lost are irreplaceable, actually," Father Duaime said.
Each window was unique, and specially made for the chapel's construction in 1909.
Meanwhile, work on the structure continued on Tuesday, as it has for several months, in preparation for the chapel's 100th year. It's a milestone for which there were many events planned, some of which will now have to be rescheduled, or cancelled.
One of the windows destroyed by the fire tells the story of Jesus' resurrection, which according to the bible took place three days after his death. Father Duaime know this church's resurrection will take a bit longer than that, but he has faith it, too, will come back.
As Father Duaime said, "This will just double our efforts."