Knit fabric is constructed from intermeshing yarn loops. Those loops can move, so knits often stretch more readily than woven fabric. Jersey names a particular knitted structure, not a fibre: it may be made from cotton, wool, polyester, viscose, or blends.
Jersey construction
On single jersey, the face mainly shows small V-shaped knit stitches and the reverse shows horizontal loops. Cut edges often curl, and crosswise stretch is commonly greater than lengthwise stretch. Interlock and other double knits use different structures and tend to be thicker and more stable. Rib knit has pronounced vertical ribs, while French terry has characteristic loops on its reverse.
Stretch and recovery
The word jersey is not enough to determine whether a fabric suits a sewing pattern. Required direction of stretch, stretch percentage, and recovery must match the fit. Elastane can improve recovery, but knit structure, fibre blend, and weight all contribute. A fabric may stretch easily yet fail to return to its original dimensions.
Cutting and sewing knits
Visible wales or rows help align the grainline. During cutting, support the fabric so it does not hang off the table or stretch beneath the pattern.
A suitable ballpoint or stretch needle is designed to work between the loops rather than damage them unnecessarily. Seams must retain the stretch the garment needs; options include a narrow zigzag, a machine stretch stitch, or an overlocker. Excessive presser-foot pressure or unsuitable feeding can make seams wave. Twin-needle or coverstitch hems provide stretch when correctly adjusted.