The commission earlier this year approved the application for a building at the corner of Jefferson Street and Park Avenue to house SHU's schools of business and education.
But the university, in plans presented Tuesday night, now wants to slightly reduce the size of the building, and eliminate some of the underground parking, replacing it with surface parking.
The university also will use the building for the business and communications schools, leaving the School of Education at its current location in Trumbull.
The commission asked that SHU officials come back and present the changes at a public hearing. No date has been set for the hearing.
The commission also had the option of finding the revisions consistent with the original application or requiring the college to submit a new application.
The exterior of the building also will be changed to brick and copper, and two wings of the structure will be pushed closer together, eliminating a courtyard.
Commissioner James Kennelly had questions about the change in use of the building and the landscaping plans.
"It's a significantly different layout," he said.
There were also questions about pedestrian flow, the increased surface parking and drainage plans.
"We have a lot of questions," TPZ Vice Chairman Seth Baratz said, "and we're speculating."
While the changes are probably consistent with the initially approved plan, Baratz said, "I don't think we have enough information."
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