The Riding School in the Royal Palace of Naples: Transformations ...

The clear span is the same of that of Niccolini’s trusses, but the pitches slope is smaller, about 31°.
The structural elements are constituted of rough-hewed timber beams and there is a floor resting on
the tie-beams, constituted by transversal joists and a chestnut plank floor. The roof covering was
constructed using purlins, chestnut planks and tiles.
This truss typology can be found in the covering system of other buildings in the Royal Palace,
where the original timber structures are still in place; particularly in the west part, which coincides
with the oldest part of the palace, built by the architect Fontana at the beginning of the seventeenth
century, timber trusses of fir still exist (fig.7), with a clear span of about 20 metres, which have a
structural scheme perfectly corresponding with that of the demolished trusses of the riding school,
also with the same pitches slope (Bamonte 2001).
Figure 7. The trusses of the west wing of the Royal Palace of Naples
The expectation of a large load to support has induced the designer, as can be deduced from the
letter just quoted, to use structural elements with a relevant cross-section as well as to employ a
larger number of them. In fact the structure of the slopes is constituted by principal rafters (308 x
409 mm), jack-rafters (308 x 308 mm) and lower rafters (286 x 308 mm), and also the tie-beam is
made by superimposing three timber elements of identical cross-section (330 x 330 mm) near the
leaning extremities, putting a timber corbel and a lower timber corbel under the tie-beam. From the
description given in the document it can be inferred that the presence of special devises to make the
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