Assessment of the Suitability of Non-Air-Conditioned Historical Buildings for Artwork Conservation: Comparing the Microclimate Monitoring in Vasari Corridor and La Specola Museum in Florence

The current energy crisis and the necessity to minimize energy waste suggest the need to assess non-air-conditioned buildings in terms of the need to install an air-conditioning system and to size and control it efficiently. This applies to historical museum buildings hosting artworks that require specific microclimate conditions for their preservation. With this view, this work analyzes the suitability of non-air-conditioned historical museum buildings to properly preserve exhibits. Therefore, two non-air-conditioned museums located in the historical city center of Florence, Italy, are considered as case studies, i.e., Vasari Corridor and La Specola. One year of indoor microclimate data monitored in representative rooms of the museums are analyzed according to the standard for artworks preservation and in terms of historical climate. Results of monitored indoor air temperature and relative humidity show that all monitored rooms are not suitable for the preservation of the exhibits without the installation of an air-conditioning system. However, to minimize the energy consumption, the hygrothermal control can be based on the observed historical climate that characterizes the environments, which presents acceptable preservation ranges much wider that the reference technical standard. In this way, the energy needs for the environmental control necessary to ensure the good conservation of the artworks can be significantly reduced.