A relatively thin flat panel of thermal insulating material is provided with an array of holes or apertures, each coaxially aligned or coextensive with a reinforcement bar emanating from a concrete slab forming an interior floor within a structure consistent with the design of a structural engineer of record. Rebar couplers (nipples) are arranged within each of the holes or apertures of the insulating panel having axial lengths greater than the thickness of the panel to extend beyond the panel on both sides thereof. The couplers are threaded both internally and externally. Nuts or threaded washers are threaded and tightened on both sides of each coupler to secure the coupler in place in relation to the panel. Alternatively, fiberglass rebars can be used extending through the insulating panel.