Energy conserving building structural elements normally called window or door frames

An improved energy conserving structural element normally used in combination with other structural components in a manner such that a relatively narrow air gap that should be thermally insulated is created between elements, said element comprising a structural member having thermal insulation means secured thereon the side therefore that will define the air gap, said insulation means comprising compressed expandable thermal insulation means having enveloping means retaining same in a compressed state, said enveloping retaining means being capable of being rendered inoperative so as to allow said insulation material to expand, said insulation material in its expanded state, having thickness to substantially fill said air gap,

• wherein the improvement comprises:
• means for recessing and enveloping said compressible expandable insulation into said structural elements outer periphery surface, said recess being used to substantially provide said envelope means;
• means for maintaining said compressible expandable insulation in a compressed mode in said recess enveloping means;
• and
• until said maintaining means is rendered inoperative.