Diagnosis of the Wooden Roof Structures of the Cathedral of Santa Maria del Fiore in Florence, Italy

The construction of the Cathedral of Florence, one of the largest churches in the world, demarks the typical skyline of the city with its huge dome. The construction began in 1296, and the church was consecrated in 1436. The considerable size of the church implies the usage of wooden structural elements that are dimensionally unique and originated from a forest in Italy that hardly finds similar examples. The importance of historical wooden structures, considered an integral part of the cultural heritage and memory, is also to be found in the safe use of the architectural asset. In 2020, a two-year project was launched, dedicated to the development of a protocol for the investigation of the wooden structure of the Cathedral roof, so as to establish its state of conservation. The final aim is to proceed with a plan for suitable restoration interventions and allow a correct restoration of the structures, thus guaranteeing a long-lasting service life of the building. The complete diagnostic followed the procedures described in the EN 17121:2019 standard. The results of the survey were elaborated and returned in tabular and graphical form to have a complete database, containing the information for each structural member and joint. On the basis of the results obtained, it was possible to carry out structural evaluations: structural analysis and verification, finite element models of the stresses, and structural assessment. The described results allow the managing body to estimate how and where to carry out any necessary intervention, fundamental for the maintenance and safety of the wooden structure and therefore of the whole building.