Mensiochronological techniques for timber elements: limits and specificities through a case study

In Italy, studies on wooden structural elements in masonry buildings, from the Middle Ages throughout the Modern Age to the twentieth century, are few in number compared to other European countries and present a less systematic approach. It is necessary to carry out progressively, but systematically, highly-detailed surveys and to correlate them with the existing discontinuous documentation. Diachronic comparisons – referring to significant geographical areas in which evident constructive constants are recognizable – would highlight the variation over time of the models and their diffusion, while the comparison, especially synchronic, between solutions evidently different or apparently similar, would allow to better understand both the constructive choices and their static behaviour. The application of mensiochronological techniques to the analysis of timber structures, especially floors, is an interesting and promising field of research. The significant measures for dating are various: dimensions and centre distances of beams and joists, width and thickness of the boards, dimension of the accessory elements (e.g. joint laths), but the variety of construction techniques often makes it difficult to identify comparable measures. In addition the working processes and tree species have a decisive impact on the measures of the artefacts. Mensiochronological techniques usually detect slow but evident variations; however, a centuries’ old constancy is equally significant. More general information about the context is useful, in particular which choices are not determined by mere technical reasons. A better historical knowledge serves to understand the qualities and limitations of existing structures, and the features – including decay – in which they appear. The floors of Palazzo Magio in Cremona, dating from the fifteenth century to the end of the eighteenth century, allow to reflect on how and what to examine.