The work of rehabilitation of the building of Ca l’Alier executed by Calaf Constructora and the UTE VOPI4-Elecnor wins the Catalunya Construcció prize in the category of rehabilitation patrimonial. Calaf Constructora was responsible for the formation of the basement through an engineering system so far never applied to the subsoil of the city. The building has been rated with the LEED Platinum label that certifies the building with a minimal environmental footprint and a very efficient use of future resources. The jury has valued very positively “the brilliant resolution of a complex project, with a great technical difficulty that can only be understood if the state of degradation in which the whole is considered”