NEW YORK | One World Trade Center | 1,776' Pinnacle / 1,373' Roof | 108 FLOORS

[SkyscrapersOfNewYork]

that last image fails to place the 2nd tower in a practical place. really all it does is disrupt the pedestrian flow in the memorial.

[SteveD]

I follow this thread pretty religiously so if the octagon question has been asked before, sorry. If it has, I hadn't noticed it.

I concur a FAQ on the first page would be great.

[Zapatan]

Originally Posted by Traynor

Your logic is impeccable but in practice it doesn't work because the floors are arbitrarily numbered.

The first 20 floors are actually more equal to 14 floors of 13'4" each, like most of the other floors.

I am not exactly sure of the math (Here is where Zen would step in and fill us all in) but trust me, 72 is the Octagon floor.

Yup, bingo, 72nd floor is 880 feet up and is the perfect octogon,

remember, it's not half way up the tower since the tapering begins 186 feet up.

[bunky]

Short preview of the 1WTC time-lapse movie i'm making:

• Video Link

[Stu]

Originally Posted by uaarkson

The twin Freedom Tower discussion is getting god damned ridiculous. Please stop.

Agreed.

This thread is about the construction of One World Trade Center. Keep it on topic. Thank you.

[MadGnome]

Originally Posted by Zapatan

Yup, bingo, 72nd floor is 880 feet up and is the perfect octogon,

remember, it's not half way up the tower since the tapering begins 186 feet up.

It's more complicated than that. The triangles on the corners aren't the same as the ones on the sides since the bases at the top are 141 feet and the bases at the bottom are 200 feet, so the midpoints of the triangles aren't the point where you have the perfect octagon. It will be higher up than that.

[jthornton17]

Originally Posted by Stu

Agreed.

This thread is about the construction of One World Trade Center. Keep it on topic. Thank you.

Agreed, we know what's getting built. Lets talk about it. This was all debated 8 years ago about what to build. It is what it is. I haven't seen any pictures today. Anybody have any to post?

[uakoops]

Originally Posted by MadGnome

It's more complicated than that. The triangles on the corners aren't the same as the ones on the sides since the bases at the top are 141 feet and the bases at the bottom are 200 feet, so the midpoints of the triangles aren't the point where you have the perfect octagon. It will be higher up than that.

There's also the fact that they are skipping a bunch of floor numbers up near the top (92-98?)so there are not really 105 floors.

[toren1776]

-Let this be the last post on this issue-

Traynor:

Your logic is impeccable but in practice it doesn't work because the floors are arbitrarily numbered.

The first 20 floors are actually more equal to 14 floors of 13'4" each, like most of the other floors.

I am not exactly sure of the math (Here is where Zen would step in and fill us all in) but trust me, 72 is the Octagon floor.

No, his logic was NOT impeccable. Don't make that assumption especially when it comes to this kind of issue. This really has nothing to do with floor height or building plans; it all boils down to the math:

Today I did a little mathematical exercise and was able to prove that the "octagon" is indeed on the 72nd floor. It took me some time to come up with, but in the end I figured out the height of the tower at which this "octagon" is found, which was 878 feet, and just about on the 72nd floor. To actually get the 878 figure, I used some pretty difficult triangle ratio methods and eventually mashed out this formula:

o=(ah/(a+b))+185

o=the height at which the octagon is found (the variable)
h=height of any one of 1WTC's triangular facades=1,183 feet
a=half of the base of any of the four larger triangle facades=100 feet
b=half of the base of any of the four smaller triangle facades=70.7107 feet
height of base=185 feet

Proving this formula would be impossible on this forum given that it is largely a geometrical proof and requires multiple diagrams to be drawn. The most important thing to know is that the facade triangles don't all have the same area (4 are larger, 4 are smaller) and therefore the octagon is a little higher up than just at the midpoint of the facade triangle height.

Also, does anyone know who first came up with the 72nd floor as the "octagon floor" that everyone keeps mentioning?

[meh_cd]

Zen, who just passed away. He had the plans for the building.

[MadGnome]

Zen didn't get fancy. He just broke out the prints and measured the floors.

[uaarkson]

Originally Posted by bunky

Short preview of the 1WTC time-lapse movie i'm making:

• Video Link

Awesome. I'm excited.

I managed to nab a sweet screenshot from the video too, hope you don't mind if I post it here.

[Kanto]

Originally Posted by uakoops

There's also the fact that they are skipping a bunch of floor numbers up near the top (92-98?)so there are not really 105 floors.

Skipping floors? Why would they do that?

[SkyscrapersOfNewYork]

Originally Posted by MadGnome

Zen didn't get fancy. He just broke out the prints and measured the floors.

this thread has become a shell of its former self since Zen left us....lately im not learning anything.

[bunky]

Originally Posted by uaarkson

Awesome. I'm excited.

I managed to nab a sweet screenshot from the video too, hope you don't mind if I post it here.

Of course, thanks for looking.

Here is a better resolution for you.

[RKOwens44]

Bit of sad news... if you check the weather report for NYC, it's supposed to rain all this week.

[davidinasia]

Originally Posted by SteveD

I follow this thread pretty religiously so if the octagon question has been asked before, sorry. If it has, I hadn't noticed it.

I concur a FAQ on the first page would be great.

It has been asked before, by me, back in November 2010.

http://forum.skyscraperpage.com/showthread.php?p=5042648#post5042648

It's quite possible that someone else had asked it before then; after all, the octagon floor is one of the obvious milestones in the construction of this building. Back then, people seemed to think the octagon would be reached a lot sooner. But, we're getting there.

[JayPro]

Not to split hairs, but 1WTCs shape, save the first and last handful of of floors, are octagonal.
That said, I am assuming the next milestone to be that point in the building's development when takes a perfect (or as near to it as possible) octagonal shape, i.e. all sides equidistant.
Frankly, I'm shocked to see her as high as she is now. I'm guessing parapet level and prelim work on the antenna/telecom apparatus by Christmas......maybe sooner????

[toren1776]

davidinasia:

It's quite possible that someone else had asked it before then; after all, the octagon floor is one of the obvious milestones in the construction of this building. Back then, people seemed to think the octagon would be reached a lot sooner. But, we're getting there.

These people probably assumed that the regular octagon would be located halfway up the tower (around the 55th floor or so) when in fact it was 17 stories higher (and some 6 months of construction later ).

[Tom In Chicago]

Moved some of the discussion of the alternative WTC plans here:

http://forum.skyscraperpage.com/showthread.php?t=190774

. . .