Valentino Castle, since 1906 it was the first seat of Politecnico di Torino, On 2nd August 2024, Turin and in particular the western area along the Po river was affected by an extraordinary atmospheric event with the fall of hailstones that reached a diameter of 10 cm. The Valentino Castel slate roof, especially on the slope towards the river, suffered considerable damage with thousands of slates breaking and moving out of place, falling to the ground or getting stuck in the gutters and downpipes. The main focus of this thesis is to assess the roof slate durability, testing slate from the actual Valentino Castel roof from Welsh slate and Spain slate under thermal cycling and freeze–thaw cycling conditions.