The researchers focus on the IRT procedure of heat diffusion in ceramic finishing materials of contemporary architecture. The aim of the research is the development of a method for the thermal characterization of clinkers, a very common ceramic finishing material of buildings. The first experimental phase was performed in laboratory on clinkers of different shapes, thickness, colors, and glazing surface. The researchers determined two characteristic parameters related to thickness and thermal conductivity, by the interpolation of the heating curve in function of time with an analytical curve (resulted from a particular solution of Fourier’s equation). This curve allows to obtain a parameter characteristic of the material of the specimens under investigation. At present time, the researchers have been studying the correlation between this parameter and the damage level in the specimens; they will be testing the model on real-scale study cases in the second experimental phase. 1. Introduction The use of clinker tiles for finishing the facades of contemporary architecture has been a common practice since the 50–60s. The durability of the ceramic materials, their low cost, their stainless and apparently low sensitivity to pollution effects, and finally the low requirement for maintenance are some of the reasons of their diffused application in the Middle-Southern region of Europe, as an effective alternative to brick-faced masonry, timber cladding, and stucco. After more than 50 years from its first use, most of the ceramic finishing shows damage due to weathering/pollution in the mortar joints and the mortar underneath the tiles [1–3] that cause the tiles detachment. Since 2010, an articulate and widespread research has been developed at Politecnico of Milano and State University of Milan, entitled “Sustainable Campus Leonardo.” The focus of the research is to involve scientists on the study, analysis, survey, assessment, management, repair, and enhancement of the universities’ campus in the Eastern area of Milano. Among these research lines, the authors developed a methodology to asses the state of conservation of the facades, especially ceramic finishing. In the present paper, the authors show the improvement of the preliminary tests based on the solution of the mathematical model of heat transfer in the ceramic medium. The preliminary test had its validation by softly hammering both the sound zone and the delaminated areas of the finishing. The different sounds revealed the detachment of the finishing. The method has been applied on historical
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