Height exceptions and limitations. The height limitations of
this chapter shall not apply to:
A. Chimneys, flues, spires or belfries.
B. Elevator or stair bulkheads, roof water tanks or cooling towers,
including enclosures, provided that such structures, in the aggregate,
do not occupy more than 10% of the roof area.
C. Flagpoles, radio or television antennas, masts or aerials located
on a building and extending not more than 20 feet above the roof of
such building.