A multicriteria approach to identify the Highest and Best Use for historical buildings

Abstract

Abstract The cultural heritage conservation is essential to preserve the memory of monuments, places and territories and to ensure their transmission to the future. This can be pursued through continuous and careful maintenance, which, however, is lost when a place loses its function and becomes prey of neglect and decay. It is easy to understand how fundamental is to assign compatible intended use to safeguard the historical goods. From this perspective, the research proposes an innovative and economic evaluation model in order to identify the Highest and the Best Use (HBU) for the historical buildings that would take into account both their social, cultural and economic identity and the preservation of their integrity and original image. The choice of HBU requires a rational study approach that can employ the Multicriteria Decisional Methods (MCDM). These Methods could allow us to consider not only the financial performance of the restoration and enhancement intervention, but also the wide variety of the effects that it will generate on the territory, by involving the community in the new functions, the employment opportunities and the project's aptitude to encourage the cultural growth, by respecting the historical and architectural values. According to this framework, the research outlines an economic evaluation protocol that implements the Analytic Hierarchy Process (AHP), a hierarchical multicriteria technique consisting in breaking down the complex decision issues into fundamental constituent elements based on multiple criteria and sub-criteria. The protocol consists in a sequence of logical and operational steps that starts from the preliminary selection of possible functional destinations among those technically feasible, urbanistically permissible, economically viable and historical-architecturally compatible; the next definition of evaluation criteria and sub-criteria; the assignment of the weights to the criteria and the scores to the use options; then the implementation of hierarchical analysis algorithms, which return the final ranking of alternatives and thus outline the Highest and the Best Use for the building. Novelty elements concern the rationalization of the phases, the selection of the criteria evaluation according to the international references for the disciplines of the conservation of cultural heritage and the economic evaluation of projects, and finally the formalization of calculation schemes. The model is validated on a real case study: the monumental Palazzo Genovese in Salerno (Italy). Here the goal of researching HBU meets the need to remove the historic building from the current state of abandonment or underuse and to give it back to the citizens, by ensuring the use and the constant care and maintenance. The application demonstrates the practical usefulness of the protocol in decision-making processes for the re-use of architecture in order to maximize the economic benefits and, at the same time, to safeguard its historical and architectural values.