The only public school on Hornby Island was partially destroyed in a fire just one week before students were set to head back to class.

Fire crews were called to Hornby Island Community School just after 2:45 a.m. Sunday after flames broke out at the elementary school.

The blaze seriously damaged the front one-third of the school while the rest of the building suffered bad smoke damage.

Hornby Island Fire Chief Doug Chinnery said when crews arrived at the building, the front exterior was fully involved and firefighters had to get past that to get to the flames inside.

He said the fire doors did a good job of containing the flames, but the biggest challenge was fire spreading in the space between the ceiling and the roof.

"We sent a crew up onto the roof and they cut a hole in the roof. They were able to get enough water into the space to stem the spread of the fire," said Chinnery. "Once we had it knocked down we had a local guy with an excavator come and he was able to pull the roofing off for us so we were able to get the rest of it done."

The building's front entry, the gym, offices, mechanical and electrical rooms were heavily damaged.

The school is part of the Comox Valley School District and houses students from Kindergarten to Grade 7.

It's unclear where students will go when classes kick off next Tuesday, but district staff say they are working on a contingency plan. Additional info will be posted on the school district's website, according to the Office of the Superintendent.

Chinnery said a fire in a community building like this is heartbreaking.

"The timing could not be worse with school going back in another week or so, and it is the only school on Hornby. I had parents coming up to me today saying that their kids were so excited to go to school and they hadn't had the heart to even break it to the kids that the school caught on fire."

Eighteen firefighters battle the blaze for several hours, with mutual aid crews from Denman Island Fire Department getting an early ferry to help.

Investigators were back at the burnt-out school Monday to continue to look into the cause, which has not yet been determined.