Expanded polystyrene (EPS) concrete presents considerable promise as a sustainable construction material, providing both structural and ecological advantages. In terms of structural integrity, EPS core sandwich wall panels (SWP) demonstrate impressive mechanical properties, as evidenced by load testing on samples. The initial crack loads were recorded between 11.5 and 13.5 kN, while the ultimate failure loads ranged from 41 to 44 kN. The panels exhibited an initial stiffness of 4.00 to 4.82 kN/mm, which decreased to 1.32 to 1.72 kN/mm after cracking, indicating a stiffness reduction of 57 to 69. Furthermore, energy absorption significantly increased, achieving values between 401.00 and 430.72 kN·mm at ultimate loads, which reflects the panels� capacity for gradual deformation and resilience. The deflections at failure were noted to be between 21.0 and 23.0 mm, with ductility ratios ranging from 7.00 to 8.33, underscoring the panels� ability to absorb energy and support loads even after cracking. On the environmental front, EPS concrete contributes to lower carbon emissions through lightweight construction, which reduces the need for raw materials, enhances energy efficiency, and utilizes recycled EPS waste, thereby aligning with circular economy objectives. EPS-based products contribute to pollution reduction and sustainable building practices by enhancing insulation, reducing transportation emissions, and managing plastic waste. By reducing landfill waste and improving indoor air quality, EPS helps to mitigate environmental effects. However, further research into life cycle assessments, synergistic applications with materials like rice husk ash, and potential environmental risks is necessary to maximize its structural and environmental efficiency. © 2025 Elsevier B.V., All rights reserved.