Doing "Fallingwater" type cantilever balconies

[Gene]

I am a builder, with a degree in structural engineering from long ago. I've never practiced engineering.

I have a client interested in achieving the FLW Fallingwater look in a new house, and the idea comes from the one shown in the attachments. One is my Sketchup model, the others are photos from an architect's website.

How do you think the cantilevers are accomplished, structurally? There are some clues in the photos.

[Gene]

I am new here and cannot figure out how to do attached .jpgs. Can someone give me a tutorial?

[mx2]

when you are writing a new post...before you "submit" there's a button below says "add attachment"...click it and follow the directions. Simple enough I think...

...anyway, one thing I don't understand is why do they want a large cantilever? Is it over a waterfall as well? It sound more like a gimmick then an architectural necessity. Regardless, cantilevers need to be engineered very carefully. This is not you typical DIY job and could be dangerous...even years down the road. Liability comes to mind, not to mention lives....

mx2.5

[nanrehvasconez]

can't comment without attachements, cantilevers can be fun and dramatic, to be used in conjunction with the neighborhood, landscape, topography.

[Gene]

I have gone that route, trying to do an attachment, but apparently this forum will not permit any unless they are from a public website.

Other forums I frequent that have this same format for posting attachments, let me do them from folders in my PC.

The house can be seen here. http://www.salaarc.com/projects/kdcof001.html

The cantilevering, as it was for Wright and his client, was all about vanity. It's like, "anybody can do post-supported terraces, but it takes GENIUS to do them like this." Kelly Davis of SALA, who did the "Marshside" house, was doing the same.

I know full well that it is not a DIY job, but it is something we want to explore.

The Marshside house is a feature of Sarah Susanka's first book, "the Not So Big House," and its section includes some good photographs. Those, plus the photos at the website, give some clues as to how Davis did it.

I am sure steel was used. The clues are in the pictures that show views looking both ways in the great room, and note when looking through the glass doors, how you can see what look like Cor-Ten steel columns, against the outside walls, between doors.

The firm of Harrison and Abramovitz did an all Cor-Ten skin when they designed Pittsburgh's USX tower, and massive columns climb the exterior of the curtainwall. It looks as if Davis is emulating this detail in the Marshside house. If you take the photos from the website, blow them up with some photo software, and study carefully, you can get an idea of the scale of the "columns." My guess is that what you see is not the real thing, but a fabrication in either wood or sheet metal.

Steel members that big would be total overkill, structurally, in this house. I am guessing (and will pursue this further) that square tubular steel members run inside the faux columns, outside the walls, and for the upstairs cantilevered balcony (8' x 8'), there are steel trusses buried in the 3' tall sidewalls, welded to the columns, or bolted. The columns are sufficiently tied into the second floor frame, and in fact the second floor frame might have two 8W10 beams cantilevering out to help share the balcony load. They can reach inside 17'-4 before they dead end in a bearing wall adjacent a staircase.

I sure wish I could post some pics of my Sketchup model, in which I am trying to work out this structure.

[csintexas]

Use an image hosting site like photo bucket of Flicker

[nanrehvasconez]

"The space within becomes the reality of the building"

Frank Lloyd Wright, Architect





Frank Lloyd Wright (1867 - 1959), Fallingwater, Kaufmann House,
Bear Run, Pennsylvania, 1936.
What is Architecture?
Architecture is the art of building. It satisfies a basic, universal human need for shelter.
An architect is an artist who designs structures to enclose residential, commercial, or public space. Architects work with construction technologies, building materials, topography, contractors, and governmental regulations within a project budget to satisfy their clients' wants and needs.


fALLING WATERS IS A BRIDGE CROSSING THE CREEK, THE CANTILEVER AREAS ARE REINFORCED CONCRETE AND DETAIL OF THE CONSTRUCTION CAN BE OBSERVED IN ANY OF FLW MANY BOOK

[mx2]

Okay then...firstly, that is correct: Fallingwater was done with reinforced concrete. However, most importantly, the image you showed us, Gene, is not much of a cantilever, especially in contrast to what FLW did and what made his particular feat rather spectacular.

See picture:

[phansford]

Fallingwater is unique to Wright's late career. By 1914, the cantilever in Wright's work went from an expression of "exploding the box" to decorative fodder. Midway Gardens is the best example of the cantilever as decoration.



At Fallingwater, the house takes it forms and ques from the limestone rock of the site. The idea is the house is an expression of living in a cave or under a rock outcropping.



There are only a few works after 1914 that added to Wright's importance and impact on the whole of architectural history. The Oak Park period is considered the high water mark by most historians, with unique masterworks to filter in after that date. (Fallingwater, Johnson Wax, The Guggenhiem) - otherwise he was mostly running in place. The star system kept him in vogue. As an architect you either copied Wright, Corbu, or Mies......or (ugh) TAC (Gropius at his worst) those were the three "Schools". Guys like Louis Kahn were a breath of fresh air. (Don't get me wrong - I love Wright's later work..... but very little of it rises to the level of his Prairie Houses. )

What you have to understand is the cantilever was an essential part of the horizontal expression of the prairie in Wright's early work. Many midwest architects still practice in the "Prairie" style and the cantiliver or over-sized roof eaves is a mark of the style. (Remember there were many others working in the Prairie style during the early part of the 20th C). In other words...... these early Prairie houses of Wright's were nearly all built on flat city or suburban lots. The Robie House nearly covers the entire site - there is little or no yard. (it sits on a corner lot)



I see no problem with you wanting to design/build in a style that provides you the opportunity to incorporate a cantilever. You might want to study Wright's early work and stay away from discussing Fallingwater. You might get more out of looking at these examples......

The Westcott (Springfield, Ohio) - note the cantilever is used to capture space for two sleeping porches.



Any of the lesser known Oak Park houses...... can be found here

[ExperiencingArchitecture]

It sounds like the client is not hiring an architect but coming up with his own ideas, and we have a builder/ engineer seeking to study FLW type structures to see how they work structurally. This is fine. But at some point some professional consultation should be done, as the house and structure should be designed in totality at once, together with expert knowledge. And simply studying photos of structures may not reveal all the details that went into designing the same - but makes certainly for an interesting exercise in structural analysis.

[Micke]

Sorry, but no help with any engineering advice on cantilevered structures, but I will say that I think they're quite unique. Was FLW the most successful at this design or were (are) there many architects doing this? The SALA site sure does have some unique designs.