PRECAST CONCRETE MAJOR STRUCTURAL BUILDING COMPONENTS, NAMELY, HOLLOW CORE SLABS, BALCONY SLABS, ARCHITECTURAL CLADDING PANELS, INSULATED LOADBEARING AND NON-LOADBEARING ARCHITECTURAL PANELS, INSULATED LOADBEARING AND NON-LOADBEARING GREY WALLS, SOLID ARCHITECTURAL OR GREY LOADBEARING AND NON-LOAD BEARING WALL PANELS, BEAMS AND COLUMNS