Northwestern Bank’s signature Northern Prairie Style as designed by Bob Cornwell, made its debut with the design of the Elk Rapids office. The design of each Northwestern Bank office continued the theme with variations as to tower placement and window usage. The banks feature a lobby, waiting area, offices, teller area, and work area. The ceiling of the lobbies are vaulted with exposed timber trusses and a translucent skylight on the roof allows the lobby to be filled with natural light. Pendant lights, which hang from the timber trusses, and also light boxes, which shine light up at the vaulted ceiling all along the lobby, create a warm and dramatic visual appearance. The bank offices are constructed with wood stud walls, split-faced concrete block veneer, limestone sill and lintels, brick veneer, with synthetic stucco at the tower and building ends, and standing seam metal roofs. On May 6, 2009, Northwestern Bank’s Suttons Bay office became the first bank in Northern Lower Michigan to be LEED Certified by the United States Green Building Council.