Which invisible technology? Metadates for the ret-rofit of historic buildings

The energy recovery of historic buildings is made particularly complex by two criti-cal issues, as well as due respect for the principles of protection. The first is the lack of real data on the energy behaviour of the historic envelope, in the absence of a systemat-ic performance survey to create design guidelines. The second is linked to cultural as-pects that, as immaterial and "invisible", are difficult to quantify and govern within cur-rent management processes, characterized by huge amounts of information made avail-able in the form of numbers. The paper aims to investigate the use of the current digital tools in the retrofit interventions of historical buildings, as a solution for overcoming the two delineated criticalities.