Abstract: An overhead bi-fold door is provided having an upper section and a lower section which are hinged for movement relative to one another between a closed flat position and an open folded position. Each section includes side beams and a frame spanning the side beams which is recessed in relation to an outer surface of the side beams. Sheeted insulation is received within the recess on an outer side of the door so that cladding may be supported across an outer side of both the sheeted insulation and the side beams. The sheeted insulation being supported on an outer side of the frames provides an uninterrupted layer of insulation of constant thickness to prevent thermal leakage which otherwise occurs when insulation would normally be supported on an inner side of the frame in sections mounted between the frame members.