Abstract: An air supported multi-wall insulated structure formed of a flexible impermeable, impervious or imperforate wall and a permeable, pervious or perforate wall defining juxtaposed cavities or compartments between the walls, filled with insulating material such as particulate expanded polystyrene material and the process of inflating the envelope and then filling the compartments with the insulating material by blowing the same into place. In certain embodiments, the perforate wall forms the inner wall. In another embodiment it forms the outer wall. In still another embodiment the impermeable wall is the central wall and perforate walls are on both sides of the impermeable wall. In still another embodiment the central and outer walls are impermeable, forming the air space and the inner wall is perforate and contains the insulating material.