Abstract: An insulating panel for inhibiting the passage of radiant and conductive heat into or out of an enclosed structure through the attic, foundation, windows, doors, and skylights where the panel is laminated. The core of the panel is of extruded polystyrene or expanded polystyrene having a thickness of between 1/16 of an inch to 1½ inches. The core of the panel is coated with a fire retarding material which can be an adhesive and which is used to attach a metalized film such as aluminum to each side of the core. Apertures are located in the core and metalized films to allow air to pass through the panel, and the panel is scored to allow it to be folded.