A second story setback is common in houses designed with “prairie school” elements.
By second story setback I mean this: the second floor plan is smaller than the first, and exterior wall lines for second floor are set back from those of the first floor below. Take a 40×40 main floor, a square, and set a 32×32 square second floor on top. Like a square-cornered version of a wedding cake.
Here is a view of a house with a second floor setback. Ignore the wingouts on the main floor.
If you want to do a dramatic room on the main floor, one with ceiling volume clear up to the roof, you need to figure a way to support those upper walls. That is what is attempted here.
In this xray view, you can sort of see the structure inside.
The windows in the second story work the same way, architecturally, as clerestory windows. In fact, they are clerestory windows, the clerestory being those second floor walls which rise atop the lower roofs. You can see if you look closely at the xray view, how the wall under those windows is shortened, and some posts are going down to something.
Here is a view from inside the “tall” room, which takes up about one quarter of the basic footprint of the house. Now those posts are quite visible, and as can be seen, they bear on beams that intersect, and then bear on outside walls so as to transfer the roof load down through slender columns between firstfloor windows. Ignore the view through the windows, as the software does not tilt the background when it tilts the house for the view.
This crossed-beam-with-posts-above structure was used by architect Sarah Susanka in at least two different houses she designed. I know this because the look is seen in photos in one of her books, and the houses are distinctly different otherwise in finish and form.
A study of architecture and building through the ages would probably turn up this structural solution having been used by gothic cathedral builders, and timber framers building large public buildings in the middle ages, and even today in private homes.
Think about it. If you sat with paper and pencil to figure a structural scheme for a two story vault under a setback corner, you would probably arrive at this crossed-beams-with-posts arrangement, as one of the few means of doing this without columns below.
The question now is this. Is it copyright infringement to use this design feature in a house you design?
Edited 7/23/2009 5:44 pm ET by Gene_Davis
Edited 7/23/2009 5:53 pm ET by Gene_Davis
Replies
It may occur in Susan Susanka's designs but it is very similar to the post and beam structure used by Osburn and Clarke years earlier. So yeah, she is in for years of litigation once I tell on her - and from now on I'll keep an eye on you too!
Why cross beam? What is the logic of carrying two of the beams to the exterior when they are interrupted by the other two?
Why cross beam? What is the logic of carrying two of the beams to the exterior when they are interrupted by the other two?
Can you explain? What other two?
They don't have to cross, but at least one needs to go to the exterior wall to pick up a bearing. One homeruns into the wall, the other heads off into it and is clipped there with a heck of a big custom hanger.
View Image
"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
I thought you were referring to them as cross beams because in your interior view they are shown crossing with what must be a dummy beam beyond the "heck of a big custom hanger" put in for looks?
That doesn't look right to my eye. I'd go ahead and put a column under that crossing. 40'x40' room? Jeebus!
So the entire second floor is supported by two big beams and 4 columns ?
Is it copyright infringement to use this design feature in a house you design?
I would say no, not any more than it would be copyright infringement to use floor joists as a design feature to hold up a floor.
There are several ways to hold up a floor, but joists are the most common way to do that. As you point out, this crossed beam arrangement is probably one of only a very few ways to hold up a clerestory wall without using full-length posts.
That being the case, it seems to me that it kind of falls into the public domain.
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
Is it copyright infringement to use this design feature in a house you design?
Probably not, as the engineering is likely to be individual.
Now, if you copy somebody else's construction details for that verbatim, then you might be standing into danger.
You could probably use the FLW Usonian clerestories, outright, they'll be public domain by now--more of a trick in specifying very complex engineering in wood with little or no insulation mor etan anything else.