The timber truss dome of the Bellini Theatre in Catania: its history and construction

The Teatro Massimo Bellini in Catania was begun around 1812 and finally opened in 1890. The decorated saucer dome that covers the hall of the theatre is a complex timber truss structure combining decorative and structural functions to form a coherent architectural whole. It seems to blend perfectly with the other parts of the great building, but the long and troubled history of its construction cannot be perceived through the perfection and harmony of the assembly. This history turns out to be anything but irrelevant for our understanding of the constructional features of the dome, to the point that some particulars cannot be grasped without taking into account the complex designing and building process, of which the last step was the construction of the dome. The various changes made over the years, because of the countless afterthoughts about the type of theatre it was meant to be, gave rise to construction problems for the whole building and even for the truss dome, forcing the last architect of the theatre to introduce modifications which would otherwise seem incomprehensible. The independence of the timber truss dome from the overlying roof is probably one such modification and introduces a significant difference with respect to the decorated ceilings commonly used in nineteenth-century Italian theatres, which were generally suspended from timber roof structures. The paper analyses the dome by interrelating different knowledge tools, from documentary and archival research to direct surveys of the building: a deep understanding of the structure gained in this way enabled us to compensate for a number of gaps in the surviving documentation.