Guastavino Vaulting at the National Building Museum is the Daily Pic by Blake Gopnik

Deep under New York City Hall sits this gorgeous abandoned subway station, with vaulting by the great Guastavino firm that ruled the most ambitious American ceilings of the early 20th century. The firm is the subject of a lovely little show at the National Building Museum in Washington. Rafael, the patriarch, got his start in Spain then moved to the U.S. in 1881, bringing along a way of using specially made tiles to roof vast expanses with a thin skin of ceramic. Both the engineering and the tiling were done pretty much on the fly, by rule-of-thumb, but it seems that not one vault by the firm has ever had a loadbearing problem. When today’s masons built a 1/2 scale reproduction of a Guastavino vault for the D.C. show, they had to support it with wood framing as they went – as the Guastavinos never did. A sad factoid from the show: Not all that long ago, contemporary engineers at the Metropolitan Museum couldn’t figure out how to judge the statics of an old Guastavino vault there; baffled by their predecessors’ craft (and maybe shamed by it, too), they simply ripped the roofing out.

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