A recent trip to Fallingwater was a red-letter day for me. This summer my daughter Elizabeth hosted a group of Japanese exchange students, here for a short course at Pitt primarily involving our relationship with the environment. The climax of their tour was a visit to Frank Lloyd Wright’s architectural masterpiece in the Laurel Highlands.
Originally it was intended that we (Beth, her daughter Rachael, and I) meet the group in Oakland and travel to Fallingwater on a chartered bus with the Japanese visitors and a handful of Beth’s Pitt students. Unfortunately, one of the girls came down with Covid, and it was decided that we should drive there separately. A minor inconvenience, but not a tragedy.
They picked me up and started into the city, intending to get on the Turnpike at Monroeville. Almost immediately, tragedy did strike; we learned by cell phone that the bus had failed to show up at the appointed time, leaving two Japanese instructors and fourteen students stranded. Strangers in a foreign city!
While navigating traffic on the Parkway East, Beth managed, with a lot of help from Rachael and a second cell phone, to contact an off-duty dispatcher from the bus company. We quickly learned that there had been a breakdown in communications. The bus had arrived much earlier and been unable to locate its potential passengers. The dispatcher immediately contacted her supervisor and the very annoyed driver; he was persuaded to return to the bus garage and follow through with the charter. He eventually found his riders and set out for Fallingwater, about ninety minutes behind schedule.
Beth then got in touch with the folks at Fallingwater, explaining her problem; they too were sympathetic and agreed to find a way to shuffle their schedule and “shoehorn” us in. By now we were well on our way, tooling down the Turnpike and grateful that so many people were going out of their way to resolve our problem.
We arrived there at about 2:00, checked in at the Visitor Center, had coffee and a scone, and then investigated the small museum area there. This was particularly instructive. The most prominent architectural feature of Fallingwater is, of course, the massive cantilevered overhangs extending out over Bear Run and its waterfalls.
It is well known that there were structural problems with the overhangs, requiring massive repair about thirty years ago.
I knew the problem was related to the amount of reinforcing steel in the concrete beams that support the overhangs and was preparing to explain this complicated technical problem to our visitors once they caught up with us. Sure enough, prominently displayed in the museum was a large specimen of reinforced concrete with the “rebar” exposed.
Much of the exhibit was dedicated to this specific problem. Overhangs (cantilevers) bend significantly at their supports, stretching (tension) at the top and shrinking (compression) at the bottom. Although concrete is inherently strong in compression, its ability to accept tension is nearly negligible. We structural engineers remedy this by inserting reinforcing steel into the concrete to accept the tension.
Frank Lloyd Wright understood this phenomenon and indeed specified that eight, one inch square, reinforcing bars be provided at the top of each support beam. At some point Edgar Kaufmann Sr. became concerned about Wright’s design and asked Metzger-Richardson Engineers, a local firm that had a history of good work for him, to review it. They promptly reported that the design was inadequate and prepared a set of drawings doubling the amount of reinforcing steel.
For some mysterious reason the contractor “split the difference”, installing twelve one inch bars instead of the sixteen Metzger-Richardson specified. This appears to have been just enough to prevent immediate collapse but insufficient to prevent long term sagging. Mr. Wright was incensed when he learned that his design had been superseded, initiating a series of vitriolic letters between him and Kaufmann. Had this partial remedy not occurred, the damage to his reputation would have been severe.
By the 1990s the cantilevers had sagged so far that unsightly temporary supports were installed. An independent structural analysis was performed, and permanent repairs made by installing tensioning tendons. We are now confident that the cantilevers have an indefinite life.
This version of the dispute was new to me. For most of my life I have heard that some uneducated concrete foreman had arbitrarily added rebar because it was obvious to him that this high-brow architect had no idea what he was doing. Somehow that is a better story than the current one.
The bus arrived at 3:00 and we were subdivided into two groups and set out to tour the masterpiece. Our guide was knowledgeable and bent over backwards to make certain that our foreign visitors clearly understood the points he was making. I think this is the fourth time I have been through the house; each time I appreciate things I had missed earlier.
I was surprised to see all the concrete painted a faded orange shade. The guide reported that Mr. Wright’s original color scheme – light ochre for the concrete and Cherokee red for the structural steel – had recently been discovered and replicated. This also provided the answer to another question. On our way in, Beth had asked why the concrete on the two Turnpike overpasses at Donegal was painted yellow – obviously this is homage to Fallingwater.
Our guide carefully highlighted the large number of Japanese woodblock prints scattered throughout the house and mentioned the influence Japanese art and architecture had on Frank Lloyd Wright. The furniture and other accessories in the house certainly enhance its architectural elegance.
All told, it was an extremely successful afternoon for our guests. In these negative times with the news dominated by the Ukraine War and the attempted assassination of Salman Rushidie, it is encouraging to realize that half a dozen complete strangers pitched in to help Beth convert a potential tragedy into a very satisfying experience.