Re: Question?

Mark C. Langston (
Tue, 20 Jul 1999 16:23:51 -0700

On 20 July 1999, Joseph C Fineman <> wrote:

>On Tue, 20 Jul 1999, Ron Kean wrote:
>> A practical problem with very tall office/residential buildings is
>> that the overhead associated with servicing the upper floors takes
>> up so much space on the lower floors, and costs so much, that the
>> building becomes uneconomical. Many elevators must be provided, for
>> example, to service a very tall building, as the occupants would not
>> want to wait 40 minutes every time they want to take an elevator.
>And, N.B., every shaft needed to serve an additional floor takes up
>space on _all_ the floors below, so that the space lost to elevators
>per added floor increases with the height. Eventually a point is
>reached where the space added by going up one more floor is canceled
>by the decrease in usable space on the floors below, so that nothing
>is gained -- *assuming* that the idea is to create usable space. If
>you are just trying for a height record, no expense spared, then
>presumably you can do at least as well as the natural relief of the
>earth's surface, and if you imagine another order-of-magnitude
>increase in the strength-to-weight ratio of the materials, then of
>course the sky's the limit.

I believe you also have to take into account the pressure differential between the top and bottom of the building. Unless you want to have the entire top offices sucked into the elevator shafts every time you open a door. :)

Mark C. Langston	     			Let your voice be heard:

Systems Admin
San Jose, CA