Dendrochronological dating of the timber roof of the Basilica di Santa Croce in Florence

The Basilica di Santa Croce (Basilica of the Holy Cross) is one of Florence's most iconic buildings with its simple and at the same time monumental architecture, as well as the numerous works of art it contains. The roof's timber structure was dendrochronologically analysed, determining the tree species used, dating the timber and, thereby, identifying the building's principal restoration phases and maintenance work. The church roof is mainly made of silver fir, although other species like oak, sweet chestnut and ash are present, which were mostly used for cantilevers or as replacement timber. With regard to the timber's date, the various elements would appear to separate into groups. The most numerous group has high correlation values with several reference chronologies for the year 1288 (terminus post quem). These timbers probably form part of the Basilica's original construction. A second group of structural elements, with a terminus post quem of 1729, would indicate an intense phase of restoration in the mid-18th century.