425 ILCS 68/10

(a) A municipality may by ordinance require that a truss construction emblem be affixed to the front of all or any class of structures, excluding residential structures, within the municipality that have truss construction. (b) A county may by ordinance require that a truss construction emblem be affixed to the front of all or any class of structures, excluding residential structures, within the unincorporated area of the county that have truss construction. (c) Where individual structures, excluding residential structures, with truss construction are part of a planned unit development or subdivision, the municipality or county may require the truss construction emblem to be displayed at each entrance to the development or subdivision rather than on each individual structure.