Historic Structural Detail: Inconsistent

by Don Friedman on October 25, 2016

The U.S. Realty Building, 115 Broadway, is the fraternal twin on the right without the cupola. The cupolaed tower is the Trinity Building, 111 Broadway, OSE’s current home.

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The practice of history is inherently simplifying.* We have to select which facts are important to us out of a potentially infinite number of facts. One side-effect of that simplification is that it’s easy to lose sight of the fact that people at the time don’t know the future. We do, because we’re living in it…but of course we don’t know our future.

To be a bit more specific, the designers and builders of early skeleton-frame buildings had no way of knowing that the future of skeleton design was to eliminate any pretense of mass in the walls. We don’t look twice now at all-glass curtain walls, but they are not necessarily part of skeleton-frame design. The walls on old frame buildings are often very thick and very solid. In addition, the design of curtain-wall supports and lintels was still in its infancy before 1910, and the mass and strength of the supposedly-non-structural curtain walls is comparable to many bearing walls. So, how did the designers of the U.S. Realty Building (1907) create large openings at the basement level** for the retail space windows? By using an old-fashioned masonry detail: an arch.


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There’s nothing to criticize here: it’s strong, stable, fire-resistant, and fits the architectural requirements. It is, however, unexpected. This is a steel-frame building with a curtain wall. It’s not supposed to have masonry details like that. But it does, and that feels like an anachronism to us, because we know the post-1907 future.


* For some discussion, try What Is History?

** Originally a bank vault, now a restaurant.

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