In this phase mix for the construction of sandwich panel is selected. The experimental investigation involves in the preparation of light weight foam using expanded polystyrene (EPS) as core material. Two mixes were selected 1:3 & 1:4 with water cement rat io of 0.4. In this mix part ial replacement of cement by fly ash at the level of 50% and fine aggregate is partially replaced at the level of 25%, 35%, 45% and 50% by expanded polystyrene. Mechanical properties of the above mixes have been found and compared. As for face material partial replacement of cement is done using silica fume at the rate of 5%, 10% and 50% in order to improve the compressive strength of the mortar. The flexural strength of the mortar is increased by us ing steel meshes. Based on the mechanical properties of the mixes the mix suitable for sandwich panel is selected.Polystyrene (EPS) is one such material generally used for packaging or insulation. EPS is non-biodegradable and hence if released into the nature after its use, it may not decay through natural means. Hence, reuse of EPS is beneficial in terms of environmental protection. The reuse could be in its natural form consisting of beads or in a modified form obtained with heat treatment or it could be various other forms of polystyrene waste.