The Downers Grove Fire Department responded to Good Shepherd Lutheran Church in the 500-block of 63rd Street, between Washington and Fairmont, just after 6 a.m.
"They did make an aggressive interior attack to attempt to extinguish the fire, but the fire continued to over their heads, so they backed out and eventually, were able to extinguish the fire from where they originally had to," said Downers Grove Fire Department Chief Scott Spinazola.
While the cause of the fire is under investigation, ComEd crews were working down the street, replacing a pole after a motorist ran into it Monday morning before the fire. High voltage lines that service the church were also damaged.
The congregation's president told ABC7 the most severe damage was to the fellowship hall and preschool area.
"I'm told the fire started on the back of the building, where our electric service and the gas line were," said Good Shepherd Lutheran Church Congregation President Bill Merchantz.
Multiple preschool classrooms are unrecognizable, and much of the roof is gone, with damage down to the floor.
"We have the best families, and they've been so great, and I just, I'm thankful this didn't happen while we were in school, thankful that everybody is safe," said Good Shepherd Lutheran Academy Preschool Director Kat Blumer.
Jonathan VanWyngaarden is a former Good Shepherd Preschool parent.
"The first thing we saw was where his classroom was with the roof caved in over it," VanWyngaarden said. "It's heartbreaking to see. It looks like it's right over where the kids go to school."
Good Shepherd Lutheran Academy Principal Barb Koch said the school was supposed to start Aug. 21, and most enrolled are preschoolers.
"It's like kind like my second home, and it just kind of just got burned up. So, it's weird," said Good Shepherd Lutheran school graduate Nadia Blumer.
It's only been one day, but church officials said they are working to find options for the school year, including, perhaps, partnering with other church communities.
"I think it's an opportunity to reach out and work with other Christian communities to come up with a solution for all the parents that we have," Merchantz said.
"This is a bit of a shock, but we are letting our families know what happened, and we are meeting tonight to start planning," Koch said. "There was no one in the building, so that's a blessing and God has a plan for us, so we'll see what that plan is."
While it is unclear what will happen for the start of school for students, the congregation's president said Saturday and Sunday worship will happen in the parking lot if need be.
"As for worship, it's August. We'll worship in the parking lot. We're not worried about that. That will be OK," Merchantz added.