Abandoned industrial buildings are characterized by a fragile image which makes them unworthy;however they maintain quality and potentiality that can be explored by new solutions and strategies of intervention. Inspired by issues related to reuse and recycling, a new paradigm can be formalized: unused and abandoned existing industrial buildings maintain a latent energy that can be reactivated by new strategies of reuse; like a bottle made of plastic, an architecture can be reused before throw it away through demolition. In this case, reuse is preferable than recycle. The question is: how can we reuse an architecture that is compromised by many factors like the pollution of the soil? We need a change of paradigm: if less changes will take place on buildings, than lower will be the energy required to produce them. Different renovative strategies can be classified according to the relation between intensity of the intervention and level of the modification pursued. At the same time, public administration should take an active role in the involvement of private actors: the real possibility of reducing the untenableness of urban development models will be realized on the development of new strategies and tools. Through the description of some european cases, the article will present different solutions constructed on a layering of materials and meanings.