Multi-Criteria Comparison of Mivan, EPS Panel and Fly Ash Geopolymer Systems for Sustainable Lean Housing in India

The construction industry generates about 36% of global energy consumption and 40% of CO₂ emissions, while material waste exceeding 30%, schedule overruns and cost escalation underscore the relevance of lean construction principles. This study compares Mivan aluminium formwork, Expanded Polystyrene (EPS) core panel systems and fly ash geopolymer block masonry against conventional reinforced cement concrete (RCC)-clay brick masonry for a G+3 residential building in Pimpri-Chinchwad, Pune, India, using a controlled quasi-experimental design comprising material characterisation, direct and life-cycle cost analysis, thermal performance assessment (U-value, time lag, decrement factor), embodied-carbon quantification (ISO 14044:2006) and lean waste metrics via the Last Planner System (LPS). Mivan achieved the highest schedule savings (54.2%) and lowest material waste intensity (11.2 kg/m2 GFA); EPS panels achieved the best wall U-value (0.31 W/m2K) and lowest 30-year life-cycle cost (INR 148.60 lakhs, 18.5% below conventional); fly ash geopolymer blocks achieved the lowest construction-phase embodied carbon (38.6 kg CO₂-eq/m2, 65.8% below clay brick) and the highest compressive strength (31.2 MPa). Weighted multi-criteria analysis ranked EPS panels highest (3.85), followed by Mivan (3.65), fly ash geopolymer (3.50) and conventional (1.95), showing that single-phase cost analysis alone is insufficient for technology selection since a life-cycle perspective incorporating operational energy and embodied carbon systematically reverses cost rankings. These findings provide evidence-based guidance for developers, contractors and policymakers pursuing sustainable mass housing in India.