Abstract: In a preferred embodiment, a composite structural member having a pair of spaced apart longitudinally extending parallel flanges and a plurality of thermally insulative conductive web connectors intermittently disposed between the flanges, the web connectors having a pair of opposing ends, each end being attached to a respective flange, wherein at least two of the web connectors are longitudinally spaced apart from each other, thereby forming at least one open cavity defined by at least some portion of the flanges and the at least two web connectors, whereby the web connectors and the open cavity minimize thermal conductance between the flanges. The present invention includes a method of producing the composite structural member.