REDIS: A value-based decision support tool for renovation of building portfolios

Renovation of the existing building stock is getting increased attention in many European countries. One decision to be made by the professional building owner is the prioritization of which buildings to renovate within a building portfolio. This article proposes a new, value-based decision support tool, REDIS, which can support the professional building owner in this process. REDIS provides a framework for dialogue in the pre-design stage of renovation projects, and calculates a Renovation Value Factor for each building, based on a number of criteria weights, building status data and estimated renovation costs, indicating which buildings give the building owner most value for money if renovated. The REDIS tool is demonstrated through an application example using real data from a case of selecting which school buildings to renovate within a portfolio of 56 schools. Representatives from the municipality that owns the 56 schools compared the results of the REDIS tool to the results of their original decision process, where ten out of the 56 schools were chosen for renovation. The result from the tool differed from the original decision results. The evaluation results indicated that the REDIS tool supports the building owner in choosing which buildings to renovate within a building portfolio. The contributions of this study are the proposed decision support framework and the tool prototype, with the major contribution being to encourage a structured dialogue among the decision makers.