The building height limitations of this Zoning Ordinance shall be modified as follows:

   1.   Chimneys, cooling towers, fire towers, grain elevators, monuments, penthouses, stacks, stage towers of scenery lofts, tanks, silos, water towers, ornamental towers and spires, radio or television towers or necessary mechanical appurtenances may be erected to a height in accordance with existing or hereafter adopted ordinances.

   2.   Public, semipublic or public service buildings, hospitals, sanitariums, or schools, when permitted in a district, may be erected to a greater height than otherwise permitted in the district if the building is set back from each property line at least one foot, in addition to the minimum yard requirements for each two feet of additional building height above the height limit otherwise provided in the district in which the building is constructed.