Patent ID: 8667995

Claim:
An HVAC duct for use in an HVAC system, the duct comprising: an outer tube having a fully continuous external perimeter; an inner tube capable of conveying forced air, the inner tube extending within the outer tube and along the outer tube; a plurality of support elements spanning between the outer tube and the inner tube, the elements extending along the inner tube and the outer tube lengthwise, the elements defining a plurality of channels between the outer tube and the inner tube, wherein the outer tube, the inner tube and the elements are fully unitary, wherein the channels containing a plurality of thermally insulating layers, wherein the outer tube, the inner tube, and at least one of the layers having a combined R-value between about 8 and about 12, wherein the outer tube having an R-value greater than the inner tube, the at least one of the layers having an R-value between about 7 and about 10, the outer tube having an external surface with a white reflective area.