“Mechanization Takes Command”. Indoor Environmental Control in 20th-Century Historic Buildings

Before industrialization, architecture itself was designed for ensuring specific microclimatic indoor conditions. When “mechanization takes command” – citing the title of a volume by Sigfried Giedion –, this task was transferred to the Heating, Ventilation and Air Conditioning (HVAC) systems. Starting from a reflection on this pivotal passage, the present paper focuses on the indoor environmental control in 20th-century historic buildings. In so doing, it outlines an investigation concerning the building-plant system of some significant case studies: Villa Tugendhat in Brno, the Salk Institute for Biological Studies in California and the French Cité de Refuge. Attention is focused on both the plant solutions implemented during the realisation of these iconic buildings and the restoration interventions that have been carried out for their preservation. The aim is to underline the relevance of restoration interventions capable of not removing the historic plants and, at the same time, not implementing an uncritical musealisation.