Twentieth-Century Architecture/Interventions. Microclimate, conservation and sustainable design

In the global scenario, increasingly marked by international challenges related to sustainable development and climate change, it is necessary to look at cultural heritage buildings also from a “climatic” point of view. This would lead to the adoption of useful strategies to ensure their preservation and improve the consumption of energy resources. With reference to the relationship between energy and people’s comfort, twentieth-century architecture is emblematic of the transition from traditional to innovative solutions: beginning in this construction era, HVAC (Heating, Ventilation and Air Conditioning) systems became an integral part of the architecture itself and, consequently, nowadays require special attention in conservation strategies. This paper furthermore investigates the technological systems used in iconic renovation interventions carried out in Portugal in the second half of the twentieth century and the first decade of the new millennium, analysing the dichotomy between traditional and innovative technologies in the built heritage. The aim is to reflect on energy efficiency in historical building contexts, by focusing attention on the issues of microclimate and conservation, and highlighting the multiple facets of sustainable design, also in aesthetic and cultural terms.