Abstract: A prefabricated sealed composite insulating panel for use in commercial and residential buildings. The panel has an insulating core sandwiched between an outer board layer and a skin material that is capable of radiating heat. The insulating core and the skin material are positioned so that they are offset with respect to the outer board layer such that the insulating core and the skin material extend beyond the outer board layer on one lateral side and on one transverse end. The insulating core and the skin material are recessed, with respect to the outer board by equivalent dimensions, on an opposite lateral side and on an opposite transverse end. The insulating core is completely surrounded and encapsulated by a plastic channel that protects the insulating core during transportation and installation. The composite panel, according to the present invention, provides a completely sealed panel that can be easily and efficiently installed on-site.