Rosenbaum letter

SDR · Post by **SDR** » Sun Mar 20, 2016 10:07 am

I wonder what the seven dotted vertical rectangles are, in the section drawing. How about a second photo of that sheet, showing the notes which are off-camera to the right ?

Note the very slight camber of the roof-top plane. Flashing is shown at the edges of the roof. These drawings presumably contain as-found information as well as the work done by the restoration architect -- differentiated only by the notes. Are the drawings dated ?

SDR

JimM · Post by **JimM** » Sun Mar 20, 2016 10:35 am

I wondered about those dotted rectangles too. Not called out on the plan, so it's hard to tell whether of significant structural relevance. But they do appear to be placed at strategic members. Perhaps they're simply vertical blocking stiffening the stacked horizontal members?

Tom · Post by **Tom** » Sun Mar 20, 2016 1:52 pm

I have assumed that they are nailers that tie the 2x's together. But it's not called out on the drawings.

Tom · Post by **Tom** » Sun Mar 20, 2016 3:13 pm

This set of plans is dated 7 Jan. 2000.

The set contains roof framing plans, building sections, a few building details, and some site work drawings. No overall elevations or overall dimensioned plan drawings.

There are two framing plans of each condition: existing and restored.
The plan we've posted so far is the existing carport plan. All framing plans are drawn at 3/8" scale.

The building sections are only drawn in the restored condition, there are no existing building sections in the set. They are drawn at 3/4" scale.

It might make sense to post the restored framing plan of the carport next. Yet this raises the question of what to post? We'll take requests.

( You would never know by looking but they essentially put a hipped roof on this building of 1/8" per foot slope.)

SDR · Post by **SDR** » Sun Mar 20, 2016 6:22 pm

So, the original roofs were flat -- as recounted in Stanley's letter ? That brings up the issue of what appears in the Taliesin drawings of these flat-roofed houses: the sections never show any pitch-to-drain at all ?

SDR

Tom · Post by **Tom** » Sun Mar 20, 2016 6:32 pm

Yes, I believe they were flat and not pitched in order to drain. I also think most were finished with three or four ply tar and paper with a little gravel sprinkled on top, at least that's how John Christian's roof was done and he said it never leaked once and exceeded it's lifetime expectancy about a decade.

The new roof on Rosenbaum is a single ply membrane. We'll get to that with the drawings.

SDR · Post by **SDR** » Sun Mar 20, 2016 6:46 pm

Here are Tom's additional and improved drawing photos.

original

improved

SDR · Post by **SDR** » Sun Mar 20, 2016 6:49 pm

Is it no accident that a C7 fits nicely into a W8 like that ? I suppose not . . .

Sweet. SDR

JChoate · Post by **JChoate** » Mon Mar 21, 2016 11:18 am

It's exciting to 'look under the hood' as these framing plans allow us to do.

I'm interested in the scale of the steel employed in Rosenbaum's carports. It's doing a lot of work to cantilever that far with only 8" depth, and way less than the 2/3 back span that we're always told we need. But, I can comprehend the possibility of that cantilever working.

Another cantilever that has left me amazed/confused is the amazing carport at Goetsch/Winckler, which appears to have no fulcrum support opportunity at the outermost face of the carport cantilever. I can see how one beam would be supported extending out from the work space area, however, the outer edge of the cantilever remains mysterious to me.

There is a current day configuration that does a similar thing -- the carport at the new Usonian House at Florida Southern. It, too, has an opportunity for back span on one side, but the other side extends way back before it hits the house.

Since they've documented their building process, here are some photos of one of the big beams they used. It appears to be very deep coming off the truck -- looks over 2 ft. deep. I don't think this is the carport beam, because there's a photo of it installed elsewhere. So, the carport beam remains a mystery to me.

https://www.flickr.com/photos/140080283 ... 6037953992

See the photo of the carport roof framed. The steel visible from underneath appears to be intersected with cross members, (a detail I've used but it requires field welding rather than bolting). Even though I see the photograph of the carport roof working, it's still hard to fathom that the steel on the long side can be that thin and extend that far. I wonder what the allowable deflection was in the engineering calculations.

Roderick Grant · Post by **Roderick Grant** » Mon Mar 21, 2016 11:44 am

There was an article about restoring G/W many years ago, 80s I think, in Fine Homebuilding. The principal thing being addressed was the roof. There were drawings of it for that article. SDR, you have that issue, don't you?

DavidC · Post by **DavidC** » Mon Mar 21, 2016 1:22 pm

Roderick:

I've an online archive of Fine Homebuilding that runs from 1981 - 2009. After doing a search, there is no article on G/W listed (though, there is one on Hollyhock from 2002).

David

Roderick Grant · Post by **Roderick Grant** » Mon Mar 21, 2016 1:28 pm

Well, it's in one of those periodicals. I know I have it, but I cannot find it. I'll look around the mess that is my library.

DRN · Post by **DRN** » Mon Mar 21, 2016 1:47 pm

G/W was featured in an article in "Old House Journal" in the '90's. The article was titled "Cantilever Tales". In it is photo of the carport framing with the roof sheathing removed, as well as a framing plan. I donated my copy to SDR's library when I was downsizing my collections to move into Sweeton...he may have pics.

SDR · Post by **SDR** » Mon Mar 21, 2016 3:11 pm

Here is that article from the Old-House Journal:

SDR · Post by **SDR** » Mon Mar 21, 2016 3:24 pm

I'm afraid the article misses the opportunity to illustrate clearly what changes and additions were made to the original steel framing.

Here's a better look at that original framing plan:

As I see it, there was an opportunity to pass a W8 the full width of the roof, from the carport, over the kitchen and through the chimney masonry, into the living-room alcove roof. This wasn't done, however. Even the earliest photos of the house show a slight deflection of the carport roof; see this view through the kitchen windows: