... Then constructe steel joist with metal pendants,put into thermal insulation meterials,decorative stone meterials be fixed at the end. ... just needs fix hardware based on architecture drawing,put thermal insulation adhesive mortar and fix HEIFS Composite Panel . We leave out ... Pre-cast the steel plate , steel joist , Putting into thermal insulation . We need thickness of stone 10--15mm , not 25--30mm ...