Typically, the structure of old monumental buildings differs significantly from that of contemporary ones. The massive walls, large indoor air volume and the small windows, compared to the opaque portion, drastically affect the microclimates of such constructions. In such buildings is often quite difficult to perform a detailed monitoring campaign of the main microclimatic parameters. In this regard, experimental methodologies and non-invasive equipment, able to minimize the impacts on the building and on its users, should be adopted. This research describes the methodology applied to carry out the monitoring campaign on the Milan Duomo, one of the biggest Cathedrals in Italy. The campaign was carried out by means of non-invasive measuring instruments, in order to keep the building intact and ensure the smooth running of the activities. In a second stage, sensors for the long-term monitoring were installed according to the most significant and accessible points inside the Cathedral. The data collected during one year of monitoring was used to characterize the hygrothermal behaviour of the Cathedral, in order to assess the risks for the main materials which sacred objects, artworks, organs, sculptures and furnishing are made of. The future developments of this work are oriented towards the realization of a simulation model aimed at designing and planning proper active or passive solutions to improve the microclimatic conditions for both artwork conservation and the comfort of visitors.
COVER LETTERDear Editor, historic buildings have an inestimable cultural and artistic value, and contribute to provide a sense of identity for the cities and their inhabitants. The indoor microclimate of such buildings play a significant role in the conservation of the finishing, the construction elements and the artifacts contained in such spaces. In this respect, the present paper aims to analyze the environmental behavior of the Duomo (Milan Cathedral), through an experimental monitoring using non-invasive measuring instruments, in order to keep the building intact and ensure a negligible interaction with other activities. The characterization of the indoor microclimate is fundamental to evaluate the risks and subsequently ensure the proper conservation conditions for the church's materials. The present study aims to analyze the environmental behavior of the Milan Duomo, one of the most famous masonry monument in Italy, using a methodology to characterize the internal microclimate. The selected case-study is particularly relevant due to its size (i.e. the second largest church in Italy), building typology (huge thermal mass), turnout of visitors and churchgoers (more than 4.000.000/year) and presence of different materials (e.g. marble, iron, wood, canvas, etc.). The research work represents the first comprehensive microclimate assessment in the Duomo ever carried out, with the scope to analyse in detail the possible risks for the artefacts and the building itself. The methodology adopted could be used by researchers, specialists...