The invention related to an insulating, double-knit fabric having a width and a length and comprising a first knit layer and a second knit layer coupled with the first knit layer forming a plurality of rows of lofted fibers separated by rows of air spaces. The air spaces extend along the length of the insulating, double-knit fabric for the entire length of the fabric and the lofted fibers extend in a direction having an orthogonal component with respect to the at least one of the first knit layer and the second knit layer.