Regenerative Design Tools for the existing city. HBIM potentials

About 25 years ago, the so-called digital revolution came forcefully into archi-tectural domain radically changing the way architecture was designed, document-ed, represented, visualized and even built. Lines traced on paper were first con-fronted and then quickly overcome by digital mathematical entities created by Computer Aided Design (CAD) systems. Nowadays, we are witnessing a similar shift this time from CAD to the Building Information Modelling (BIM), a system that shows the ability to manage the fragmented but interconnected information needed in the building workflow in an “all-in-one” environment. However, while BIM is already a powerful option for new structures, for exist-ing ones (especially when historical) it still reveals inadequate. This issue, seriously affecting the future of the built environment, cannot be ignored in order to control the “shaping” of buildings and cities and especially when their design aims at be-coming “regenerative”. In this framework, this paper will try to outline the many difficulties connected with the application of BIM to the existing building stock: a problem that is gen-erally regarded as “sectorial” but that on the contrary will be crucial in view of a probable generalized adoption, considering that existing constructions represent about 70% of the whole European stock.