The enhancement of Modern Heritage buildings is nowadays a challenging issue as they are often degraded or abandoned and their historical value is not well acknowledged by potential buyers and their owners. Moreover, they are usually energy inefficient and obsolete, but investments for energy retrofit interventions are not always convenient, especially in socio-economic contexts characterized by weak real-estate market dynamics. This paper aims to study the influence of intrinsic and extrinsic characteristics on housing prices and, in particular, to understand whether elements of building cultural connotations or some housing green features are monetized by the real estate market. The UNESCO site “Ivrea, industrial city of the 20th century”, located in the weak real-estate context of the Eporediese territorial area, was selected as an emblematic case study and two data samples of property listings were built to perform spatial regression analyses. The results showed that the green features of housing, such as the heating type and the EPC level, have a greater influence on property prices than those characteristics related to the cultural connotations of a building, such as the Olivettian context. Therefore, the current incentive-based policies for energy efficiency can represent great opportunities that can be exploited both to preserve and to improve the condition of this valuable Modern Heritage.

This review aims to provide a general framework of the literature on economic sustainability and financial feasibility for RECs, focusing on the challenges related to the building stock and architectural heritage energy retrofit with the purpose of reducing running costs. In particular, this review analysed 95 research papers, focusing on the main used economic evaluation approaches and indicators for the assessment of a new or an existing REC. Results showed that the implementation of RECs deserves to be examined with a combination of complementary approaches able to guarantee a balance between economically sustainable and renewable energy systems and the buildings’ cultural, architectural and historical values. The articles data sample of the present research highlighted the presence of numerous methodologies and approaches that need to be combined to evaluate all the aspects of the RECs. Future research could develop a comprehensive methodological approach to evaluate the RECs’ economic sustainability by considering economic, energy and social benefits and preserving the buildings’ cultural value. This review draws a state-of-the-art of economic approaches and indicators for RECs to support the future developments of a standardized evaluation procedure in the context of the currently evolving regulatory framework.