As they allow to read and recognize the characteristics of an architecture, the surfaces have often been subject to analysis on: execution methods, human and natural transformations and conservation techniques. In the past, authors have argued that the surface must be preserved as a register of transformations, which are important aspects for the project of intervention also considered an opportunity for knowledge. For these reasons, innovating the tools of knowledge is still important even if there are firm points shared by the scientific and professional community in the field of Restoration. In this contribution, the Harris matrix method for historic timber structures has been updated, considering the long debate that this application has fueled in the past and recently. The methodological proposal on the architectural complex of San Nicolò in Ferrara was tested, in order to verify the effectiveness of the matrix for the representation of structural members and nodes and its potential in directing the intervention. The latter must always ensure compliance with the minimum intervention, effectiveness, sustainability, recognisability and the necessary balance between Conservation and security issues, also in reference to Consolidation.
