Analysis of the Determining Factors for the Renovation of the Walloon Residential Building Stock

Abstract

The issue of energy retrofitting of existing building stock occupies an increasingly prominent place in energy transition strategies in Europe. Adopting models representing the building stock and accounting for occupancy influence on final housing energy use must be developed to advise new policies. In this respect, this study aims to characterize the Walloon residential building stock and to analyze the existing correlations between the stock’s technical data and its occupants’ socioeconomic data. This study uses existing databases on buildings and inhabitants in Wallonia. Several statistical analyses make it possible to highlight the preponderant criteria and existing correlations between these different criteria. This study affirms the importance of accounting for certain socioeconomic categories, such as low-income groups, in a global strategic reflection on energy renovation. Multiple linear regression shows us that each percent increase in the category of households that declare between 10,000–20.000 EUR of income per year corresponds to an increase of 7.22 kWh/m2·y in the average energy efficiency of the built stock. The results highlight the importance of focusing on renovation strategies for particular types of buildings, such as semi-detached houses, which combine unfavorable technical and socioeconomic factors. Thus, the results confirm the interest of a mixed model approach to adapt to effective renovation policy strategies.