I'm sorry if I'm chiming in too late, but Wright designed these shallow cold weather foundations in places like Wisconsin with Taliesin (North). I have a book that he wrote toward the end of his life called "The Natural House" where he describes how it works and clearly these buildings are still standing. Reading Wright's writing can be painful, but this book has a lot on interesting info in it. Unfortunately, it's been out of print since the 60s.
Wright said he got the idea from the old Welsh masons. Instead of digging 3 1/2 to 4 feet to get below the frost line, he would only dig about 16" deep and pitch the bottom of the trench to drain. He would then use broken stone (not gravel) the size of your fist, which he claimed would not get clogged with soil. Because the trench allows water to drain under the foundation it doesn't need to be dug below the frost line, thus saving thousands of dollars in digging and concrete.
Like much of his inventive foresight, the book talks a lot about designing houses for the masses (Usonian period) as he saw the surge of the mass produced cookie cutter homes of the 1950s as a threat to our profession and boy was he Wright. It also discussed sustainability issues, hence the title, "The Natural House". In part he was disgusted by all these unnatural materials that were being developed at that time. Of course back then, he didn't call it green design or sustainable design. It was just plain old Good Design. The "Glass Box Boys" of Europe were fascinated with all these new, unnatural, modern materials and he was mocked for being the has been.
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Eric Rawlings AIA
Owner
Rawlings Design, Inc.
Decatur GA
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Original Message:
Sent: 08-30-2013 22:31
From: Jean Terwilliger
Subject: Pole Barn Construction for Commercial Buildings
This sounds like a good place for following the principles of "frost protected shallow foundation". Lots of info out there- here's one place to start: http://www.huduser.org/publications/pdf/fpsfguide.pdf. I was looking at doing something like this for a client who wanted to turn a pole barn into a residence- many passive houses are being built using similar foundations.
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Jean Terwilliger AIA
Principal
Jean Terwilliger, AIA, Architect
Cornwall VT
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Original Message:
Sent: 08-29-2013 17:39
From: Joel Niemi
Subject: Pole Barn Construction for Commercial Buildings
The "Post Frame Advantage" group is actively promoting this construction approach for commercial buildings.
"Perimeter insulation" as a search phrase brings back no results. I'd suggest treating the edge of the slab-on-grade like any other slab on grade -- R-10, or whatever your local code requires, as far down as the slab edge turns, at least.
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Joel Niemi AIA
Principal
Snohomish WA
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