The bulge measured 2 feet by 3 feet and protruded a few inches from the wall.
Superintendent Joseph Hattrick said he, Fire Marshal Mark Shay, a structural engineer and an architect considered only closing the affected wing of the building. But he said they decided closing the entire building was the safest option since they don’t know what caused the issue.
"We're not willing to take the risk of lives to keep the building open," he said "It's better to do due diligence, close the building, make sure that everything's safe, remedy whatever is going on before we make any further decisions."
Steve Mitzel, the district's executive director of operations, said that on Thursday the bulge was so severe that it jammed a door shut.
"When something happens that drastically, that means something shifted. It's not something that happened over time," he said. "That brings a high level of concern."
Hattrick wrote in an update to district families that the closure is due to “possible lateral movement of a load-bearing wall that makes the building unsafe to occupy at this time."
The district held an emergency school board meeting Thursday night.
The closure comes just a few days before classes begin Monday. About 75 students in alternative and specialized programs will be relocated to other school district buildings, which Hattrick said have enough space to accommodate them.
Lincoln School was built in 1926, and the affected wing was added in 1948. The building served as an elementary school until 2005.
Mitzel said the district has been trying for five years to secure a grant for a seismic retrofit.
District officials expect Lincoln School to remain closed for months while they stabilize the building, determine the cause of the problem and make repairs.
"We need to figure out what happened and what caused that shift to happen," Mitzel said. "Typically, when that happens, it's usually water intrusion, which we didn't see any sign of water intrusion, a shift in the foundation or in the actual infrastructure of the building. It's problematic because the integrity has been lost in something in that building there."
The building is now under strict safety protocols, and entering the school requires the presence of a safety monitor.
