Le coperture del Palazzo centrale dell’Università di Pavia: conoscenza per la conservazione programmata

Over last decades in building industry there has been a tendency to pass from interventions done after decay occurred to planned and preventive maintenance. Acquired the importance of preserving even the most perishable elements, in the field of historical heritage, planned maintenance has been renamed planned preservation: repair and conservation replaced the substitution of decayed elements. Such interventions cannot disregard the knowledge of technical elements and of their composition in the technology system. For drawing up a planned preservation plan, we need investigations sufficient to provide data for estimating their deterioration risk, and therefore to set periodicity and type of controls and of maintenance activities. The paper will discuss the historical and technological study of the roofing system of the central Palace of the University of Pavia. The palace undergone radical renovations and expansions during centuries, and it reached current configuration after the annexation (mid 20th century) of the former site of San Matteo Hospital. The stratification of construction phases makes morphology and structure of the roofs particularly complex, however a systematic documentation of them was lacking. The study made it possible to detect expeditiously, but in a sufficiently reliable manner: geometry of slopes and load bearing structures, layers supporting the roofing, points and routes for accessing to the various parts of the attic. The information collected and systematized constitute the basic documents for the evaluation of risks associated with the infiltration of water from roofs and for the definition of intervention and maintenance strategies, the subject of the subsequent phase of the research.