Historic Structural Detail: Inside

by Don Friedman on March 9, 2016

A problem that we face again and again at OSE is that so much of the structure we deal with is not visible. People have to take our word for what’s hidden behind plaster and carpet, and a lot of the old structural systems are difficult to visualize if you’re not familiar with them. Probes are not helpful, as it only helps to see the small portion of a structural element exposed by a probe if you already have an idea what you’re looking for. Sometimes the early stages of demolition help:

TC Flat Arch

That’s one of the clearest pictures of a terra-cotta flat tile arch I’ve seen. The changing slope of the joints, the “skewback” blocks that sit on the steel beams at each end, the fill layer above, and the internal webs inside the blocks are all visible. Again, I doubt that someone who had never heard of a tile arch could make sense of all of it, but at least a picture like this gives us a fighting chance to explain what the floor is and how it works.


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