Off-Site Construction. The Economic Analyses for the Energy Requalification of the Existing Buildings

The issue of energy efficiency in buildings is now of prime importance, both in terms of financial and environmental impacts. In this sense, the broad literature is expressed in agreement. The theme, which is certainly important for the entire construction sector, is analyzed here taking as a reference the off-site construction, sometimes little investigated in sector studies, both with regard to new buildings and with regard to existing prefabricated buildings. In the first case, in fact, new buildings must comply with the increasingly stringent energy standards that national and international regulations prescribe; in the second case, prefabricated constructions with low energy performance are widespread in many countries, for which efficiency measures are required. In both circumstances, however, the market is increasingly tempted to the problem, for reasons not only of housing comfort but also purely monetary, also attributable to the greater appreciation that a high energy performance has on the market. In this perspective, the paper first articulates the phases of an investigation protocol to be re-purposed in the definition of the interventions to be implemented for the energy efficiency of buildings. Subsequently, with specific reference to existing prefabricated buildings, it aims to select alternative processes capable of increasing the energy efficiency of vertical opaque structures. The preliminary technical selection of possible actions is followed by the necessary financial analysis. This, by comparing the investment and operating costs with the revenues generated by the savings on consumption, makes it possible to establish the best intervention option.