Dal progetto di conoscenza al disegno del costruito: l‘esperienza dell’ospedale vecchio di Enna

New building processes into the already built environment cannot be planned without a complete understanding of the reality on which they are supposed to be undertaken. It is necessary for the architect to found his work on a perfect knowledge of the "place", capturing its soul and character, retracing all the changes that have accompanied it over time. Therefore, this knowledge process cannot be limited to documentary investigations (albeit necessary), because the analyzed sources often provide only partial answers on the origins, transformations and changing processes of the pre-existing architectural environment. Furthermore, the collection of metric, chromatic and material data and of any other relevant information has to take into account the essential need to formulate a survey project preliminary to the intervention that, based on a critical process and in close connection with the project purposes, makes use of all opportunities offered by today's modern acquisition and restitution technologies. Starting from the assumption that to truly understand a building it is indispensable to do its practical experience, living, traveling and finally redesigning it, it appears useful to create virtual models whose exploration can provide a better understanding and an objective representation of the "reality". In particular, the most advanced laser scanning methodologies offer the possibility to create, according to the criteria of cost and time saving, a rich database of information to document, with remarkable accuracy, the complex geometry of the considered buildings; points clouds from which to obtain orthophotos and perspective representations useful to highlight features in itself difficult to recover using traditional methods. The present work, based on these principles, focuses on a wide built-up area in search of new functions, located at the hinge between the historic fabric and the 20th century expansion of a town, Enna, rich in history and culture and intensely committed to renewal.