In the next set of steel, we should see the true roof of the tower. Then the parapet will be constructed, then will be officially topped out!
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OK I found an example. If this has made my point, great - if not, maybe I will try again some day… 
Here is an example where the ‘structural steel beams’ serve a dual purpose: an aesthetic (or decorative) feature of the building AND actual structural support for the building. I think this building is ONE LIBERTY Plaza, but the same architectural feature also holds true for the SEAGRAMS building, and many others.
I think the only term I can think of “FAUX BEAMS” may not be the best (or most accurate) term to use in this type of architectural application as used here a 270 Park Ave.
When we only had renderings to view of 270; I had assumed those diamond shapes on the facade were ‘actual’ steel beams.
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Are you sure the diamonds aren’t structural inside the glass and expressed on the surface in a decorative way?
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Yeah, the diamonds are definitely structural in the sense that there are steel beams underneath the facade panels (as captured beautifully in photographs throughout this thread). But do we know whether they’re actually load bearing?
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It’s a good distinction to make – as I understand it, the actual structural diamond elements are contained entirely within the curtain wall. As TKDV mentioned in a previous post, the diamonds we see are mounted onto a backing as part of the curtain wall.
This photo by 5BFilms illustrates the distinction very clearly:
Here in Sydney, we have a Foster+Partners building which uses the same principle to create an expressed structure effect – except they did not use a separate backing panel and instead attached the beam cladding directly onto glass, presumably for cost reasons:
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The Thornton Thomasetti structural peer review mentions the diamond braces in passing, suggesting they are to provide stiffness against wind loads:
As previously indicated the steel braced core has one-story deep outriggers at levels 11, 18,
29, and 38. Supplemental diamond shaped wind bracing is also provided on the west and
east sides of the tower.
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The diamond steel members are not acting in a vertical loading capacity as the columns are though they are acting in a manner more closely associated with a column than a beam (the two of which are not interchangable), they are more so there acting in a lateral capacity to reduce lateral loads from wind. But generally, all members in a building are load bearing, whether vertical or lateral bearing, its very infrequent that you see redundant structure that is not doing anything because thats not normally something thats done.
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Right. I’m thinking more bracing as opposed to load bearing.
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I thoroughly enjoyed this! So many nice details.
It’s a great time to be a skyscraper fan—we have the tech to intimately document skyscraper construction over 1000 feet in the air and in high-resolution.
I’m in awe by those building NYC every day. After the job is done, it must feel great for those that erect these monuments to engineering (and art) to step back and see the contribution they’ve made to the ever-changing skyline.
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Subway tracks below the building site necessitated a two-story-high arrangement of steel transfer girders called the Tabletop
Setting the first column
Tabletop-construction
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Love this. I particularly like sequence where they pass the ropes up around 02:20!
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The Seagram building does not have exposed structure.
There are 4 types of buildings trying to be defined here,
1. A building that exposes its structure through the architecture (we see the actual structure).
The most well known example of this is the HSBC Building in Hong Kong. But One Liberty Plaza is also a good example even though what we see is also not the structural member, it is still encased in tight form cladding.
2. A building that does not show its structure.
10 and 30 Hudson Yards for example
3. A building that does not show its structure but replicates structural geometries on its facade.
This building as the example and the Salesforce Tower Sydney example that @ThreeWentDown shared.
4. A building that uses structural members in its facade that are not structural.
The Seagram building and a number of other LMVDR projects as well as a number of international style buildings.
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Love the sentiment in that tweet. It’s a beautiful fortress of evil.
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Am I the only one who wishes the Hemsley Building was a little taller? It’s such a great design
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Yes, but at the same time, because is not that high you get to appreciate all the amazing details from the street level.
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It was massive for its time.
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Speaking of “Helmsley” - that family fortune ended up going to the the dogs. Literally, the dog - talk about “trouble”… 
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