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Posted: Mon Mar 21, 2016 3:45 pm
by Tom
First time I've noticed a difference in the G/W carport framing plan from Affordable Dreams and the 'Cantilever Tales' article. I wonder which version was the built one?

I think the big suspended beam of the FSC house carport must be held up along it's length by the cross cantilever beams, at least one coming out near the entry door I think.[/u]

I'll send SDR shots of drawings thru the Rosenbaum Livingroom next.

Posted: Mon Mar 21, 2016 4:03 pm
by SDR
Tom, I assume that the Goetsch-Winckler carport roof framing illustration in the article is the as-found condition.




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Likewise, all is not completely well at the FSC house. The carport cantilever seems to be performing as expected -- but at the opposite side of the house, a lesser two-way cantilevered roof appears to sag, as revealed in this photo:

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The carport framing puzzles me; how could that slender member extending from the heftier one possibly take any weight ? Is it a tension member ?

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Posted: Mon Mar 21, 2016 4:18 pm
by JChoate
These are great construction photos of the framing.
They are obviously going to have to splice a beam to the left side of the cantilever, tying it back into the continuing beam (not visible behind the one running left to right). Or add some masonry to the left to do that tiny back span trick again.

It's doable to step down the beam size toward the end of the cantilever, especially where the solid roof transitions to an open trellis kind of thing.

I've tried that sort of thing on a project, where there were cantilevers holding up cantilevers. The danger is cumulative deflection where each incremental deflection adds to each resulting in the total amount at the outer edge. It is very helpful to omit roof mass at the outer extents which lightens the load on the moment arm of the cantilever.

https://www.flickr.com/photos/140080283 ... 653629520/

Posted: Mon Mar 21, 2016 4:55 pm
by SDR
Right. What I don't get is the sudden transition, in the first photo, from large beam to small, with what appears to be a welded connection. The thing looks like a hinge point,
to me. Or does the small beam continue into the large one, with the lower flange hidden in shadow ?

Wright loved these two-way cantilevers -- the real demonstration of anti-gravity architecture. Rosenbaum is one thing, G-W another.


This may be the perfect G-W photo, comparable to our favorite of Rosenbaum ? Anyone who won't admit that Wright was a consummate stylist, has "issues," if you ask me !


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Posted: Mon Mar 21, 2016 5:30 pm
by SDR
Tom sends further images from the 2000 Rosenbaum restoration CDs:


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Posted: Mon Mar 21, 2016 5:48 pm
by SDR
Section drawings of Wright's work by others, always seem to give new insights into the work. One sees a Japanese object in the building section above. The clarity and structural logic, the sense of shelter, the intimate human scale, and the materiality, all echo an ancient building tradition.

How does Wright achieve structural continuity in the the three-ply wall, at the junction of the opaque wall and the window band ? What material continues unbroken, presumably from the central ply, into the mullions between the windows ? Even if this wall didn't support the roof above, wouldn't it need to be kept soundly planar for its own sake ?

This particular condition doesn't appear on the Standard Detail Sheet of 1940:


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Posted: Mon Mar 21, 2016 7:29 pm
by Tom
SDR:
If I understand your last question correctly,
I think it's done (in this Rosenbaum section at least) mainly by the tapered interior supports called out in the section as: "Existing Cypress Wood Trim to Remain."
I think also between window sections there must be a solid mullion that connects the lower 3-ply solid wall to the roof framing above the row of "Existing Transom Windows."

Is this what you were talking about?

Oh, this Rosenbaum LR section reminds me of our last conversation about the same section through the Auldbrass LR. I'm noticing the small asymmetries AND the return air duct in the Rosenbaum House. That kills me. Strange to me that metal grill somehow got a pass. It may be painted brick at Auldbrass, but it could have been open like Sturges.

Posted: Mon Mar 21, 2016 7:53 pm
by SDR
Ah -- yes, that's what those stepped tapered "trim" pieces are for, surely. But no such pieces are present in, for instance, the Jacobs drawings and photos.
Nor is there a (visible) vent in the masonry above the fireplace . . .

SDR

Posted: Mon Mar 21, 2016 7:56 pm
by Tom
Yeah, so I think at Jacobs there just must be a solid piece between the transom windows that connects the roof framing to the 3-ply wall. (...And I bet at Jacob there's no duct work at all.)

This is the issue of Wright's, in my judgement, remarkable "headerless" wall sections. ...because there is always a structural roof framing member that crosses at 90 degrees directly over the middle of a 1/4" framed glass plate transom window with no header at all. That piece of roof framing cannot bear on the center of the window. So how is that piece of roof framing supported? It's supported by the exterior running fascia which is in turn held by every other roof rafter which is in turn supported by the "invisible" solid piece that must exist between every individual window transom.
It's a remarkable system. I never tire of being charmed by it.

Posted: Mon Mar 21, 2016 8:16 pm
by SDR
I hope so. Here's the M M Smith living room, the only other example of that reinforcement I've found so far. It shows up in no drawings I've seen yet.
Pope, Euchtman, Goetsch-Winckler and others are candidates lacking them.


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Nice boarded ceilings. Firebrick lines up with red brick. Coffee table aligned with grid. Smiths living bravely and nobly without rugs.


On the Rosenbaum section there's a note about removing the bottom two bookshelves (why ?) and above that a note about the shelf supports. Can you read that note ?

SDR

Posted: Mon Mar 21, 2016 8:25 pm
by Tom
Yes, I can read the note. Curious. Wonder why?

Posted: Mon Mar 21, 2016 8:45 pm
by SDR
I can't. What does it say ?

SDR

Posted: Mon Mar 21, 2016 8:58 pm
by JChoate
SDR,
That is a handsome G/W photo, but I don't think it's in the same league as our Rosenbaum photo (THE Rosenbaum photo). The house isn't as sublimely abstract, the landscape not nearly so reductive, and G/W doesn't look like it could fly nearly as fast as Rosenbaum.

The rear elevation is my least favorite aspects of the G/W house. My 2nd fav is the view from inside the lanai looking down the line of the roof overhang at the overlapping trellises. But far and away, I like most the front elevation showing the implausible carport cantilever. There is one G/W photo in particular that floats my boat. It's the one with the 60's era Jaguar E type coupe in the carport. It's high on my list of favorite pics of all time.

Regarding that Florida Southern steel beam, it looks like the top flange on the smaller extension overlaps the top of the larger beam to function as a splice plate. There's some sophisticated steel detailing (and lots of it) in that house that I doubt would've been present in a 1940's era original.

There're some squirrelly junctures in those new Rosenbaum sections. Of course, the original design details were full of naïveté (hence the letter that started this post). Wasn't the story that the roof was built first, the the walls raised underneath to enclose it. This suggests post & beam rather that platform framing, but in that one section it looks like they've diaphragmmed that upper short wall on the inside face.

Posted: Mon Mar 21, 2016 9:15 pm
by SDR
The "roof first, walls second" prescription was uttered by Mr Wright somewhere early on, though I don't know if it preceded the construction of Jacobs. A ridiculous idea, of course, and not worthy of someone who knows how building are built, and why -- but leave it to The Poet and Prophet !

Our friend DRN, owner of the Sweeton house, is a car nut like me and loves the E-type photo, as I do. (It's a 2+2 ?) If I had my way, every house built after 1936 would be shown with a Cord sedan under the carport; I may yet do some low-tech collage-shopping to get the desired effect.

The entry elevation of G-W, uniquely among the Usonians, looks disturbingly like a Bauhaus creation in some of those photos; it could be metal and glass instead of wood and brick. Too streamlined for its own good ?

Where in the FSC house does that giant pierced beam go, do you think ? Is it pierced on top to make it disappear within a clerestory ? Print out the floor plan and mark it up, if you feel like it . . .

SDR

Posted: Mon Mar 21, 2016 9:33 pm
by JChoate
I think that big perforated beam spans the living room where the upper roof steps down to the lower one towards the front of the house. On most usonians that gap between the upper and lower roofs would be filled with clerestory windows, frequently with perforated board motifs. But on the elevation drawings, the FS house has the cast concrete blocks in that place. A little of it shows up in that first photo you posted. That seems a little at odds with the 'nature of materials' -- to visually appear to support masonry on top of a wood plane, but hey, he's the Master. Nuthin' a little 2 ft deep steel beam can't handle.