Abstract: A form of insulation is disclosed that takes up less room and is more efficient than insulation currently available. It has several modes of use that make it more versatile than conventional insulation. The insulation is formed from a pair of surfaces that are sealed to each other at all edges to form an enclosed chamber, a honeycomb, a cellular matrix, or truss structure is inside the said chamber, separating the surfaces. Said chamber is evacuated and the surfaces that face the chamber are constructed to be of low emittance so as to provide an insulation that significantly inhibits the transference of heat in any manner. By using a material with a high absorbtion and low emittance on one surface and a material with high emittance and low absorbtion on the opposite surface, heat can be transferred easily in one direction but poorly in the other direction, thus acting as a thermal diode.