According to his report, there are 1,000 round barns left in America. They were built up until the 1920s. Given the advantages of such a structure, it makes you wonder why farmers quit building them:
Carpenters discovered that they required less stone or wood than rectangular barns, thus saving on costs. Because their roofs are supported by the one circular wall, there are no columns needed. So there’s more room for livestock or hay. And Midwesterners learned that high winds — even tornadoes — that would pulverize an ordinary barn often glance off a round one.
And I wasn’t aware of this problem during the Round Barn’s restoration:
Slowly it began to bulge and slump to the east, until a group of citizens bought it and fixed it up. They pounded telephone poles into the ground all around the barn, wrapped heavy guy wires around them and the barn, and pulled until the old red barn was upright again. That caused the roof to collapse, but they built a new one.
I’ve seen many photos of the collapsed roof, but didn’t know about the structure leaning. That makes me appreciate the group’s restoration even more.