After some delays, a new Catholic school is finally open in Windsor and already over capacity.

The doors to St. Teresa of Calcutta Catholic Elementary School opened for the first time on Monday, but the $8.6-million facility is already too small to accommodate all of its students.

The school was built based on an enrolment of 425 students, but there are about 520 students in the school. More than 100 Grade 4 and 5 students have class inside portables.

Principal Elise Daragon says some students may be learning in portables, but they are still inside the new buiding.

“Although their main classroom is in the portable or the portapack they have every opportunity to get into this building," says Daragon. “We think we have made very wise decisions. The teachers who are in the portapack have been encouraged to bring those children into the building as much as possible."

The Windsor-Essex Catholic District School insists it is a good problem to have, since it shows rising enrolment numbers faster than originally anticipated.

The board’s communications coordinator, Stephen Fields, says the design of the new school was based on enrolment projections in 2011.

“The Ministry of Education funds new capital builds based on projected enrollments at the time," says Fields, who points out they have seen an increase in the number of students since last June as more families move back to Windsor.

“We have a lot of students or families who are interested in coming to this school,” says Fields. “So again you fund the school based on the best information that you have at the time and that's what you build to."

Fields adds if they continue to see an increase in enrolment, there will be a case presented to fund an addition at the new school.

The new St. Teresa of Calcutta Catholic Elementary School combines students from St. Bernard, and the recently closed St. Jules schools.

It features new open concept space designed to combine classes for collaborative learning. There is also portable technology in the school, such as chrome books, iPads and laptops.

“We are almost at a ratio of for every two students we have one device and that's incredible because it doesn't replace learning in the traditional sense but it enhances it,” says Daragon. “This is a learning facility at every level from the youngest who comes to us at 3 and a half years to our staff.”

Portables, or portapacks, are not new at schools in Windsor-Essex. Both the public and separate school boards use them at different facilities.

Officials from both school boards admit new schools tend to attract enrolment that could not be calculated when construction plans were initially approved.