TIMBER REINFORCEMENTS: LOCAL COSTRUCTION TECHNIQUES IN ITALIAN HISTORICAL BUILDINGS

The role of timber connections as reinforcement for vertical masonry walls is well known but still requiring a systematic study. Considering the main sources coming from the architectonic treatises, a real identification of the use of wooden poles as binding elements between walls is not recognized. Several important authors belonging to the 15th and 16th century recommended avoiding the use of timbering elements into the section of the walls, arguing that the perishability of this material cannot provide a long durable solution. Nevertheless, since the 17th century also some indications from the so called "high knowledge" seem to identify a reliable technique in the timber reinforcements for masonry walls. This work explores the contraposition between theoretical approaches and the building site practice, focusing on the mechanical function of orthostatic timbers inserted into masonry structures. Recent contributions based on archive studies indicated that the use of wooden reinforcements was widely diffused in Italy, but rarely documented by the architectural theorists. The technical documentation discovered into archives is instead a rich source of information concerning the persistence of timbers inside walls as a solution against the vulnerability of masonry structures to shear forces. The case of the building site documentation for the realization of Volpi Palace in Como offers an important occasion for improving the studies on a building practice that did not meet official credits by the theoretical experts in architecture.