Comparative Performance of Bio-Based Construction Materials in Europe: A Multi-Criteria Decision Analysis

The European construction sector accounts for approximately 40% of EU final energy consumption and around 36% of lifecycle CO2 emissions, creating structural demand for low-carbon alternatives consistent with the European Green Deal and the revised Energy Performance of Buildings Directive. This article presents a structured multi-criteria assessment of seven bio-based construction material categories producible within the EU—wood fibre/cellulose insulation, expanded cork agglomerates (insulation corkboard), mass timber (CLT and Glulam), hemp–lime composites (hempcrete), straw bale systems, mycelium-based composites, and cellulose aerogels—evaluated across twelve sub-criteria organised under three equally weighted pillars: environmental impact, economic opportunity, and social value. The analysis integrates durability maturity as a primary market-access variable, fire performance under Wildland–Urban Interface (WUI) exposure conditions, seismic risk compatibility, and EU regional demand heterogeneity. Composite scores are calculated by summing individual criterion scores, with pillar sub-totals shown explicitly. A sensitivity analysis under three alternative pillar-weighting scenarios, a single-criterion perturbation analysis, a Monte Carlo simulation, and a TOPSIS method comparison collectively test the robustness of rankings. Results indicate that wood fibre/cellulose insulation, expanded cork agglomerates, and hemp–lime composites constitute the highest-impact portfolio under baseline and environmental priority weighting; under economic priority weighting, mass timber displaces hemp–lime in the top 3. Under environmental priority weighting, cork achieves the highest composite score of any material, driven by its perfect environmental pillar sub-score and the regenerative carbon sequestration of the cork oak. All four robustness tests confirm that wood fibre, cork, and hemp–lime occupy the top 3 positions across all weighting scenarios—with cork rising to first and wood fibre dropping to third under environmental priority weighting—and that the additive scoring method produces rankings identical to those generated by the TOPSIS method.