Construction History: What Kind of Knowledge in the Maintenance Process?

In the operative field of Built Cultural Heritage the material authenticity value is missing, in particular in the maintenance activities.This paper investigates what is the actual knowledge of Construction History, analysing the maintenance activity: the wrong customs and the regulations show how there is an insufficient knowledge. In order to change this approach the most updated theories affirm that first of all we have to innovate the cognitive process. There is need of a different look that is able to take savoir réparer as well as savoir faire. Only with this mentality it's possible to maintain the tangible and intangible authenticity, working in a sustainable way in historic buildings. This cultural shock involves a lot of consequences: in terms of social capital it means to recognize legality of repair's craftsmen, as a resource of local development; in the “intellectual capital” it means to qualify technicians with a long life learning training.