Mr. Roche designed numerous projects for Cummins, including its corporate headquarters. Although he usually declined to do private houses, he, like Saarinen, made exceptions for Mr. Miller; in 1982, he designed a lavish residence for him and his wife, Xenia Simons Miller, in Hobe Sound, Fla.

For all Mr. Roche’s delight in creating crisp, nimble architectural shapes in glass, some of his most notable early work came across as anything but light. For one of the most important projects he worked on with Saarinen, the John Deere headquarters in Moline, Ill., Mr. Roche proposed developing a kind of steel that could be allowed to rust naturally. The resulting rough, reddish-brown product, Cor-ten, became a common building material.

While the elegant Deere building, completed in 1964, was widely admired, Mr. Roche used Cor-ten to considerably less critical acclaim on two projects in New Haven: the tower headquarters of the Knights of Columbus (1969), and the adjacent New Haven Coliseum (1972). The image there was anything but light, and the rusting steel and heavy, dark brown masonry blocks and gargantuan columns gave the complex an ominous tone.

Vincent Scully, the Yale architecture historian, wrote that those buildings and another Roche project in New Haven, a sprawling concrete high school, “all share a kind of paramilitary dandyism which seems especially disturbing at the present moment in American history.”

Mr. Roche was not pleased by Mr. Scully’s view that his assertive forms somehow reflected the bombastic and overbearing elements of the United States during the Vietnam War. In the Knights of Columbus tower, in which the steel beams supporting each floor are like huge bridges connecting four enormous circular piers at each corner, Mr. Roche felt that he was really just exploring architectural ideas, experimenting with scale and trying to figure out new ways in which to organize and erect a tall tower.

Although Mr. Scully never moderated his feelings toward much of Mr. Roche’s work of the late 1960s, the two men, neighbors in the New Haven architecture community, eventually became friendly, and Mr. Roche was among the eulogists at a memorial service for Mr. Scully, who died in 2017.