Cornicioni e sistemi di smaltimento delle acque meteoriche nell’architettura tradizionale mediterranea. Conoscenza, durabilità e recupero compatibile nella Sicilia Occidentale

The essay explores the construction aspects of cornices that, from elements of protection, they can also become elements of degradation and instability due to their shape. We would analyze formal and material values of a cornice: it presents complex characters and summarizes problems deriving from construction requirements of building envelope, due to the double value of ornamentation (crowning of building) and functional component (removal system of meteoric water from façade). This study suggests a repertoire of “rules of art”: deriving from treatises and manuals and constituting points of reference for historical construction. We would indicate the main degradations that the shape of cornice can produce on façade, supported by an experimental study conducted at the University, through an experimental model, according to the most recurrent forms of cornices founded in the historical center of Palermo, comparing the obtained data with the pathologies identified by the rule UNI11182/2006. This study wants to provide specific indications that allow the technical element to be brought back to a configuration compatible with its pre-existent characteristics.