By now, it is clear the built environment could play an important role in fighting climate change, since it accounts for around 39% of global energy-related carbon emissions. Generally speaking, Italian residential stock is over 50 years old and around 16% of that needs large interventions due to its poor maintenance condition. So, the maintenance in this context can play a pivotal role in acheiving both energy efficiency and asset valorization. Introduced by a reference framework for the question in the title, this paper presents the case study: a portion of a working-class neighborhoods near the metropolitan city of Turin, marked by very recurrent typologies for the period (early seventies). The local real estate market is discussed to investigate the extraordinary maintenance impact on the property values: the paper considers the market value increase due to the energy class upgrade and the external look improvement. Individual owners putting money on this group of works get a very cost-effective investment and take advantage of Italian legislation supporting these kinds of interventions: the whole is greater than the sum of its parts and in turn greater than the cost assumed for the renovation work.

A significant portion of postwar buildings, typically concentrated in suburban areas, are now difficult assets to manage due to their poor sustainability and limited replacement feasibilities. This paper focuses on strategies to improve their metabolism using energy-saving measures based on optimizing energy needs and integrating internal and external energy sources: a new organizational model for energy management should focus first on saving energy, and then on the possibility of integration into a local energy network. This positively affects the anthropogenic impact and becomes a role model for aggregating buildings not only into a district system, but also into a wider, large-scale energy network. The paper shows a significant case study of actual retrofitting intervention that is examined in order to confirm the theoretical guidelines proposed in the first part of the paper. Moreover, another significant case study, taken from common practice, is illustrated, in which different levels of retrofitting are tested. While taking into account the complexity and fragmentation of private property both in a single building and in the city, some strategies are finally described with the aim of reducing the anthropic impact of the postwar building stock.