What makes an antenna not count in the height of a skyscraper?

Question

Really this intrigues me, whos to say that an antenna on the sears tower is not an architectural element, why can a Spire, with no purpose but decoration count more then an antenna that serves a purpose?

Answer 1

The antennas are usually secondary additions to buildings structures and not included in the super-structure of the building itself.  It's a bolted on bit at the top that isn't connected to the building in any other way.  A spire, on the other hand, is directly enter-connected to the super-structure of the building.  And to be fair, many a spires in the world have been converted to serve a purpose other than decoration.

Answer 2

Stephen R is right.  They are usually added as an afterthought and not part of the building plan.  Also, they are very light, and only connected to the buliding by a few bolts and sometimes guy wires.  So a couple hundred feet of antenna can be added to pretty much any big building without any serious modifications to the structure.  If they were counted, then any building owner could increase his building's height at will.  This would lead to ridiculous antenna wars among buildings competing for the title of tallest building in a city, or the country, or the world.

Answer 3

It is not a part of the structure.  

Do you measure your height from how high you have managed to spike your hair?