The following are permitted to exceed the maximum height regulations within any district where allowed: church spires, belfries, parapet walls, cupolas, domes that do not contain usable space, public monuments, water towers, fire and hose towers, flagpoles, flues, chimneys, smoke stacks, grain elevators, elevator penthouses, radio and television receiving antennas, satellite dish antennas when mounted on the roof of a principal structure, manufacturing equipment and necessary mechanical appurtenances, cooling towers, substations, utilities, and electric power and communication transmission lines.