When construction of a new addition on the Boston University School of Law’s campus is finished this summer, it will mark six years from conception to completion. But the spacious 93,000-square-foot, five-story structure set to replace the school’s iconic Josep Lluís Sert–designed law tower as a classroom facility almost didn’t happen.

In 2008, Boston University officials feared that Sert’s law school building would need, at the very least, a substantial renovation. The 265-foot tower, which was erected during the first half of the 1960s, had lost favor with students and faculty because of its inefficient design. University officials approached the Cambridge-based Bruner/Cott & Associates to help them assess the practicality of such a renovation—and to offer their own suggestions.

“The dean of the law school had two complaints about the building,” Leland Cott, a founding principal of Bruner/Cott, told AN. “Aside from the issue of leaking and snowdrifts in the classrooms, functionally it had too small of a floor plate for a tower and the classrooms were not easily accessible. It was a flaw in Sert’s design to put classrooms in the tower and then expect students to get there efficiently in small elevators.”

Cott and his team of designers believed that with a little ingenuity the tower could be preserved while also meeting the school’s criteria that a new facility include state of the art classrooms, a new library facility, and informal meeting places for students. The architects devised a separate building adjacent to the tower that would create more horizontal space, improve classroom accessibility, and provide room for students to congregate. The tower, the team decided, would be revamped to house the school’s administrative departments and faculty offices. Thus the Sumner M. Redstone building—named after the media magnate who gave a lead gift to the $130 million project—was born.

The design team chose limestone as the principal material because of its similar aesthetic qualities to those used for the law tower and the theology building, which lies to the south of the Redstone building. The design’s glass portions bring the project into the 21st century. Cantilevers on the north and west sides complement those Sert incorporated into his other buildings on the campus and create a dialogue with the surroundings, said Cott. The building’s central element and entryway is a 4,000 square-foot, glass-enclosed winter garden. It also serves as an informal gathering space for the student body.

For Cott, one of the challenges of the design was in keeping with Sert’s initial vision. “I knew Sert,” he said. “He was the Dean of Harvard’s Graduate School of Design when I attended. My design team frequently asked, ‘What would Sert have thought of this? Would he object?’”

Cott said that Sert would approve not only of the project, but of the effort to reinvigorate his works for a modern audience. “When you’re dealing with a master like Sert, an architect of significant importance, we look to ways of preserving his architecture and correcting the faults that people have with it in ways that will make people like it once again. I think that’s what we and Boston University have succeeded at doing.”