Architettura e costruzione. L’organizzazione dei finestrati negli edifici religiosi all’inizio del IX secolo

The study of the upper windows in the Roman churches during the Carolingian age has generally considered the inner spatial effects, helping also to find significant chrono logical markers. At the same time, some specific analyses have concerned the high medieval building techniques, focusing the characteristics of irregularity and the systematic presence of re used material in the structures of that period. The essay wants to examine in deep the building techniques of these serial windows, giving a special attention to the technique of the arch with double row of bricks. This technique is common in the churches built between the end of the 8th century and the middle of the 9th century. It appeared in the late Roman period mainly to connect pillars and has been used again within the Papal town over continuous and slender structures. This interpretation of the building system is totally new, it persisted in the religious architecture for about fifty years and then completely disappeared. The compared observation of the dimensions and the mutual relationship of the building components allows to recognize the rules and the reasons that justified this technical choice: they were probably connected to a precise structural intention, due to the exigence to improve the reaction of the construction to the earthquakes.