An insulated panel including first and second walls (5.004, 5.024) spaced apart by a predetermined distance, each wall including an internal peripheral channel formed by first and second bends, the second bend forming an internal peripheral flange (5.025, 5.056), the panel including an intermediate joining member (5.042) adapted to connect to the internal peripheral flanges of the first and second walls. The connection to a first flange can be via a slot (6.046), and the connection to the second flange can be by adhesive (5.044).