Nap

Nap, sometimes known as “pile”, is the natural direction of fibers on some fabrics. It is most

distinctive on fabrics, such as, corduroy or velvet. Stroked “in the direction of the nap” the fabric will flatten and lie smooth. Stroked “against the nap” the fibers of the fabric will feel rough and will not lie down neatly. There may also be color change when looking at napped fabrics from different angles. When laying out a pattern on such a fabric it is important to have all pattern pieces going in the same direction. When laying out pattern pieces for clothing it is best to have the nap going down the body so natural movement smooths the fabrics.

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Nap is not limited to long fiber fabrics, such as, corduroy or velvet. Some smooth fabrics will show only a color change. This fabric is also “nap fabric” and care must be taken so all pattern pieces run in the same direction. However, you can also alternate direction for an interesting effect as the color changes on the finished garment. Silk dupioni is one fabric that can have this effect because of the way it is woven.  It is important to audition this fabric in low light conditions and from a distance to be sure the color change gives the desired effect in vestments.