Preservation of the large timber roof of the Porta Nuova railway station in Torino

Torino, in 1861, was the first capital of the just unified Reign of Italy. In the same year, Eng. A. Mazzucchetti was charged for the design of the railway station of Porta Nuova in Torino, in correspondence of the arrival of the railway connecting Genova. The original conception resembles the bilateral scheme of the King Cross station in London, which is few years older. The design and construction of the station deserved contributions from the most outstanding scientists of that time, including R. Sephenson who provided the details of the lateral roof structures of the station, and the young Eng. A. Castigliano who defended his thesis on the design of the great steel vault above the rails. The two main branches were conceived with masonry bearing structure and a wide span timber roof covered with stone plates. The station, during the years, was object of several interventions, including restorations, dismantling of parts, and changes in the destination of use. Nowadays, the roof structure needs for important maintenance interventions due to the water leaking which caused the deterioration of the beneath timber structure. The present holders are considering the replacement of the entire roof. This solution is not respectful for conservation criteria, nor is affordable from an economical point of view. The present study describes the correct and sustainable approach for the structural assessment, restoration and maintenance program for the preservation of this important structure belonging to cultural heritage.