Innovative Technological Systems of Upwards Sliding Gates: From Villa Necchi Campiglio to the Late 20th-Century Architectural Heritage in Milan

Post-war architecture saw the use of technological systems for considerably complex building envelopes (windows, curtain walls, innovative claddings, ...). Milan is perhaps the Italian city where architecture best allows an analysis of the social, economic, and cultural transformations of the 20th-century. Experimental technological innovations can be found in construction systems, organization of work and businesses, and living and working spaces. If the new Montecatini headquarters can be considered a reference for the "mod-ern" office building, Villa Necchi-Campiglio represents the manifesto of the new private house. The Villa is innovative not only in its architectural language but al-so in its use of new technologies that change the way of living. This paper anal-yses how these technological systems were adopted in other architectures of the second half of the 20th-century, and how they were adapted to different contexts, patterns, materials and technologies. This analysis provides an overview of the evolution of these technologies over time, in the transition between the traditional architectural language and the contemporary lexicon. A special focus is dedicated to the upwards sliding gates manufactured and pa-tented by A.Bombelli, a company specialized in metal constructions. It was active alongside designers such as Luca Beltrami, Giuseppe Momo, Gio Ponti, Marcel-lo Piacentini, Piero Portaluppi, in relevant works now recognized as cultural her-itage. After the exceptional Vittoriano gate, A.Bombelli produced several entrance gates with the retractable upwards sliding system until the late 20th-century. This paper presents some still existing and functioning gates, through documentation and unpublished archival material of great importance for their conservation.