If you have even a passing interest in raw denim, you’ve probably heard the word Selvedge more than a few times. No, it doesn’t refer to someone who vends lettuce, selvedge refers to the way a textile has been woven.
You can spot selvedge denim by the tell-tale colored lines that often run along the outseam of a pair of jeans, but what exactly does that mean?
What is Selvedge Denim?
Selvedge outseam on a pair of Companion Denim jeans.
Selvedge goes by many spellings (selvage, self-edge, salvage) but it all equates to the same thing–the self-binding edge of a fabric woven on a shuttle loom. That definition may sound a bit jargony, but trust me, all will soon make sense.
It’s also important to note that selvedge denim is not the same as raw denim. Selvedge refers to how the fabric has been woven, whereas raw refers to the wash (or lack thereof) on the fabric itself.
How is Selvedge Denim Made?
In order to understand how manufacturers make selvedge denim, we first have to understand a little bit about textile manufacturing in general. Almost all woven fabrics are composed of two parts with two parts: warp yarns (the ones that run up and down) and weft yarns (the ones that run side to side).
To weave a fabric, the loom holds the warp yarns in place while the weft yarn passes between them. The difference between selvedge and non-selvedge fabrics is all a matter of how the weft yarn is placed into the fabric.
Up until the 1950s, almost all denim was produced on Shuttle Looms. A shuttle loom is a weaving textile loom which uses a small device called a shuttle to fill in the weft yarns by passing back and forth between both sides of the loom. This leaves one continuous yarn at all the edges so the fabric self seals without any stray yarns.
Most shuttle looms create a textile that is about 36 inches across. This size is just about perfect for placing those selvedge seams at the outside edges of a pattern for a pair of jeans. This placement isn’t just aesthetically pleasing, but practical as well as it saves whoever’s sewing the jeans a couple extra passes on the overlock machine and ensures the jeans will not fray at the outseam.
The demand for more denim after WWII, however, soon forced mills to adopt mass-production technology. A shuttle loom can place about 150 weft yarns per minute on a 36 inch wide textile. A Projectile Loom, however, can place over 1000 weft yarns per minute on a textile that’s twice as wide, thus producing nearly 15 times more fabric in the same time span.
The projectile loom achieves its speed by firing individual (and unconnected) weft yarns across the warp. This is a much more efficient way to weave fabric, what’s lost though is that cleanly sealed edge. Non-selvedge denim produced by projectile looms has an open and frayed edge denim, because all the individual weft yarns are disconnected on both sides.
Why is it Popular Today?
Selvedge denim has seen a recent resurgence alongside vintage workwear styles from the 40s and 50s. Japanese brands obsessed with recreating the perfect jeans from that era went so far as to reweave selvedge denim in new and interesting ways. Now that selvedge denim is back on the market, the small detail on the upturned cuff quickly became one of the “things to have”.
The selvedge craze has become so popular that some manufacturers have even resorted to knocking off the selvedge look and producing fake selvedge appliques to mimic the colored lines on the outseam.