The DeRoy Auditorium is a nearly square two-story windowless steel-frame building with a flat roof with broadly projecting eaves. The façades are clad in narrow gray-colored cast concrete panels with white marble chips. On all four sides, raised ribs are overlaid on the panels, terminating in Gothic arches just beneath the eaves. The ribs project about four inches at ground level, but gradually increase in depth toward the top of the building until they project almost two feet near the top. The broad eaves and curving, projecting ribs create striking shadows. The gothic arch treatment on the DeRoy Auditorium is strongly similar to Yamasaki's design of the United States Science Pavilion at the 1962 World's Fair in Seattle, a commission he received while working on the DeRoy Auditorium.