Nervi was commissioned to design the ceiling of a ballroom at the Acqua Santa mineral spa in 1952. It was the third of his ceilings to feature a construction technique of diamond ferrocemento pans, each with the same shape, but in concentric rings of different sizes. The result, apparently unintentional, was a series of interlocking logarithmic spirals, a visual effect that gained a great deal of attention. (I’ve written about the geometry of these roofs here). The two previous iterations of this technique came at the Turin Exposition Hall B (1947) and the Kurssal at Ostia (1950). At Chianciano, my guess is that Nervi had a client who knew what he wanted, but didn’t want much else. Nervi had nothing to do with the rest of the building:
Which is certainly not bad as a piece of postwar international style modernism, but also isn’t exactly structurally expressive–or legible.
The ceiling is stunning, though, and from what I can tell it has a far higher level of finish and detail than the earlier two instances, an example of Nervi learning from doing a similar thing over and over again. The Palazetto dello Sport came a few years later, and obviously learned a great deal from this project, too. One thing that is unique about this instance, and that shows up a little bit in the eyebrows of the Palazetto, is that the roof itself peels up from the concrete net toward the edges, letting in light around the perimeter of the ceiling and making the structure seem particularly lacy:
It’s in remarkably good shape, and still used as a ballroom–a number of elderly couples were ballroom dancing to lounge music in it when I snuck in. The vibe at the spa–which was also the setting for Fellini’s great film 8-1/2, was decidedly in the ballroom dance mode. The managing director gave me a tour, and pointed out that the room’s acoustics are lamentable–a predictable shortcoming in an elliptical room with travertine wall paneling. I’m going to guess that Nervi had little to do with either the shape or the finishes–the former looks like it came out of a larger response to a master plan for the park, and the latter, well, let’s just say there was probably a reason Nervi’s office always published carefully cropped photos of the ceiling alone. Sort of “from the waist up.”
It was a good day trip, too. The ‘Sala Nervi’ itself probably isn’t enough to draw architectural tourists from Rome or Florence–it’s about halfway between the two–but as requested by my gracious host, I will point out that the Spa’s waters have a reputation for curing all sorts of digestive ailments. And the taxi ride from Chiusi, the nearest train station, is 20 minutes of dramatic scenery and death-defying curves that are, in the local style, taken in both lanes at once.