Energy Renovation of the Walloon Residential Stock: Determinants, Typologies, and Integrated Approaches for Targeted Interventions

Accelerating energy renovation of existing residential buildings is critical for Europe’s climate goals. This thesis investigates the Walloon residential stock through a multidimensional approach integrating technical building characteristics, socio-economic profiles of occupants, and awareness strategies.

Chapter 1 characterizes the Walloon building stock and identifies correlations between technical and socio-economic factors. Statistical analyses highlight key determinants, showing, for example, that a 1% increase in households earning €10,000–20,000 corresponds to 7.22 kWh/m²·y higher average energy consumption. Semi-detached houses with unfavorable technical and socio-economic conditions emerge as priority targets.

Chapter 2 clusters “building–occupant” archetypes using regression analyses and K-means, revealing typologies such as low-performance houses occupied by low-income households (17% of stock) or by high-income households (11%). These insights support targeted, scale-appropriate renovation strategies.

Chapter 3 presents a mixed-methods study in a historic Liège neighborhood, combining surveys, thermography, and focus groups. Results show socio-economic factors often outweigh technical ones in renovation decisions, and that awareness and tailored engagement are essential. Challenges in rental and co-ownership settings highlight the need for locally adapted policies.

Overall, this thesis provides an integrated framework combining statistical modeling, typology-based approaches, and participatory research to guide effective, equitable, and context-sensitive energy renovation in Wallonia.