Essential information for a restoration project it is the state of conservation of the manufacture object of intervention, which survey is made preliminary during the phase of the visual investigation and completed after the physical-chemical analysis of the samples, made in the laboratory. The state of conservation is defined by the recognition of alteration forms on the manufacture; and these forms are standardized from the Normal dictionary 1/88 that uniquely defines the types of surface degradation, the causes and the forms of expression.

As for the survey of materials, also in this case all the data is plotted with a false colour mapping, with legend and fact sheets attached: in the latter it is described the kinds of degradation, their possible causes, the location on the manufacture and the phenomenology with photographic examples.

Separately, sometimes the survey of cracks is made, to be precise the recognition of masonry lesions and discontinuity, essential for the structural analysis of the manufacture: the lesions are defined again according to the Normal lexicon and classified according to their bulk as superficial and deep. The first affecting only the surface layers and can be single or diffuse (microcracking); the second ones can also be localized and not arouse special attention or be part of a common lesion framework, index of major structural problems. Then, when the lesion is visible from both sides of the wall is defined passing and it is the manifestation of a dangerous phenomenon of instability of the whole building.