Multi-criteria evaluation of wall system alternatives using a hybrid fuzzy decision framework

The selection of building materials is a critical decision in construction projects, significantly influencing structural performance, energy efficiency, environmental impact, and long-term cost. Wall systems, in particular, play a fundamental role in thermal regulation, resource use, and occupant comfort. This study presents a hybrid fuzzy multi-criteria decision-making (MCDM) model for evaluating and selecting external wall systems in residential buildings. The model integrates fuzzy set theory to manage subjective expert judgments expressed in linguistic terms and combines them with quantitative performance data. The proposed methodology applies a systematic aggregation of expert ratings, normalization of quantitative values, and Chen’s maximizing-minimizing set approach for defuzzification and ranking. A case study involving three alternative wall systems—sandcrete block wall, compressed stabilized earth blocks, and precast concrete panels—demonstrates the model’s practical application. The results highlight the model’s capability to guide decision-making under uncertainty and to support sustainable material selection. The study contributes to the growing need for structured, transparent, and reproducible tools in construction material decision-making.