Polystyrene can be used as part of a concrete slab foundation system. Usually the polystyrene comes in the form of expanded interlocking pods which fit into each other. The polystyrene adds to the thermal performance of the building and helps improve SAP performance which is vital to achieve in accordance with part L of the building regulations. The insulab system (BBA certified) only requires 450mm overall structural depth of combined beam and slab do there’s less concrete, less tonnage of steel, less site traffic and reduced carbon emissions. These polystyrene pods can be used with modular construction design as well as traditional methods of building. It can be used with piles & re -bar or engineered ground fill and unstable ground conditions. It can be used as a replacement to independent beam and block floor slabs found on deep trench fill foundations.