Multi-criteria decision-making for energy building renovation: Comparing exterior wall structures with the AHP, ANP, utility analysis, and TOPSIS

Purpose: Improving residential building energy efficiency is crucial for reducing greenhouse gas emissions. Designing resource-efficient, nearly zero-emission renovations is complex. This study addresses the need for comprehensive frameworks to holistically evaluate building part renovation measures and to provide actionable guidance for strategic planning and implementation across the building life cycle, focusing on exterior walls. Four multi-criteria decision-making (MCDM) methods identify the most environmentally friendly alternative and are compared for rank similarities and decision-making applicability. Methods: The study follows a two-stage approach: (i) applying the Analytical Hierarchy Process (AHP), Analytical Network Process (ANP), Utility Analysis (UA), and TOPSIS to rank exterior wall alternatives regarding environmental impacts and circularity and (ii) comparing these methods using the Borda technique, based on correlation and standard deviation metrics and the Wojciech Sałabun (WS) coefficient. A qualitative assessment from a planner's perspective is also included. Results: The results show that different MCDM methods consistently rank the most environmentally friendly renovations, offering clear guidance for strategic implementation. This offers actionable guidance for strategic planning and implementation. The top five alternatives remain consistent across all methods, with slight ranking variations. AHP ranked first by Borda scores, while UA leads by WS coefficient. Curtain walls with timber cladding emerge as the most sustainable choice, outperforming metal cladding and insulated composite structures. Conclusions: The AHP, ANP, UA, and TOPSIS support selecting environmentally friendly building parts. UA and TOPSIS, being more sensitive to emphasized criteria weighting and relatively more applicable in practice, are recommended for building parts’ decision-making.