Selvage denim is a particular type of denim fabric which features natural edges that resist unraveling. Selvage, which is also sometimes spelled selvedge, is a corruption of the term self-edge, referring to this characteristic of the fabric. This type of denim is popular among designer and premium brands, and commands a higher price than normal denim.
What makes selvage denim unique and more expensive than regular denim is the fact that it is made on traditional shuttle looms, rather than more modern projectile looms. As a shuttle loom works to weave the denim in one continuous thread, it eventually reaches the end of the fabric. In finishing this end, the loom creates the self-edge of the denim.
For decades, shuttle looms were the primary tool for making jeans in America, until the popularity of denim clothing exploded in the 1950s. To meet demand, manufacturers switched to projectile looms, which were much faster and used less fabric per pair of pants. It was not until the 1980s that Japanese designers saw a niche for selvage denim. Purchasing many of the old American shuttle looms, they began producing so-called premium denim and charging extra for it. Since that time, selvage denim, and the old shuttle loom weaving methods, have regained popularity, and enjoy high demand despite their expensive prices.
Projectile-weaved denim has frayed ends and must have separate stitching done to finish the length of fabric. A good example of this is a typical bargain pair of denim jeans. With separate threads, rather than one continuous thread, used in the weaving of the fabric, the inseams and other ends are ragged and prone to fraying. On a selvage pair this will not happen, even past the cuff. Also, projectile loom jeans are generally lighter in weight and less durable than selvage jeans.
In both modern and vintage selvage jeans, the ends of the fabric are stitched with thread contrasts in color to the denim. This is usually red, but is sometimes green, white, yellow, or another hue. The original reason for this was to signify the end of a piece of fabric. It remains a stylistic effect, used to help identify a piece of denim as selvage.
Though they are both commonly used to make premium-quality jeans, so-called raw denim and selvage denim are two different things. Raw denim uses natural indigo dye, as opposed to synthetic dye, and is not washed or distressed at the factory. It is up to the buyer to break in raw denim jeans, and appropriate special care — such as cold water washing — must be taken. Selvage denim generally requires no special care beyond that of regular denim.