Looking at the Damage

The damage to some of the curtainwall in South Florida is very odd because the storm, Hurricane Wilma, was not bad, as described in "Wilma Pounds Florida, Cuba with Surprising Strength" (ENR 10/31 p. 12). At this time we think it was a category one hurricane.

We have some glass buildings in Coral Gables with complete curtainwall around the four sides, and the high-rise glass had not a bit of damage. Yet right across the street was a glass high-rise with considerable damage.

I think this is evidence of poor review of the plans when they came in for permitting, or poor inspections during construction if these designs did not meet code standards.

Even the old pre-Andrew code had graduated wind loads that go up in an exponential pattern as you go up in height, and would have taken care of the high-rise buildings in this situation.

HERBERT S. SAFFIR
President
Saffir Engineering
Coral Gables, Fla.

Strictly Speaking

I was reading about the tall buildings being planned or currently under construction in the story, "Skyscraper Envy Lives On, Globally" (ENR 10/31 p. 10). I do not think that a tower or spire on top of a building should count when calculating the building height in the competition for the world’s highest building. Only those portions of the building that are habitable should count.

For example, the Eiffel Tower included an apartment at the top, whereas the Empire State Building height includes a mast [dirigible mooring tower] that should not have been included in its calculated height.

If the architect really wants to include a mast as part of the design and wants it to be included in the building height, he or she should put a habitable office or apartment at the top of the mast with some enclosed way–ladder or stairs–to get to it.

Another example is New York City’s Trump Tower, where the first habitable floor above the ground floor is numbered 20. There are no habitable floors between the ground floor and floor 20. Thus, the tower floor located 200 ft above the ground floor should have been numbered 2 and not 20.

MICHAEL L. STOIANOFF, P.E.
Anchorage, Alaska