Value-based decision making in the pre-design stage of sustainable building renovation projects–exploring two methods for weighting criteria

Renovating our existing building stock holds a great potential. However, as the complexity of renovation projects is high, multi-criteria decision-making methods can support the decision makers throughout the renovation process. This study explores two value-based decision-making methods: the analytic hierarchy process (AHP) and weighting, rating and calculating (WRC), in how they support decision makers in weighting criteria in the pre-design stage of building renovation projects. Participants from a Danish municipality were given the task of applying AHP and WRC to prioritize a set of renovation criteria. Four themes were analyzed: (1) practical applicability and decision transparency, (2) reflection and learning, (3) satisfaction with the final decision and (4) comparison to the original decision process. The results indicate that applying a formal weighting method in the pre-design stage of renovation projects increases the reflection, learning, transparency and satisfaction with the group decision outcome among the participants.