As a consumer shopping for a new piece of outdoor gear, fabric terminology can be a bit confusing. The old “apples to oranges” analogy often applies when comparing backpacks made by different companies, of varying fabrics and feature sets.
Spend a few minutes(or hours, or days) Googling and you will find more information than you likely bargained for on the molecular composition of various materials as well as peer reviewed studies measuring relative performance. Paralysis by analysis can set in quickly.
In this blog post I’ll attempt to give a quick colloquial breakdown for all the laymen out there. Disclaimer: What you’re about to read is some opinion and some fact all mixed together. Feel free to disagree in the comments.
Denier is a measure of the weight of the yarns that comprise the fabric. The higher the denier the heavier and typically burlier the fabric. The lower the denier the lighter and typically more delicate the fabric. Classic, heavy duty 90’s packs were often made of 1000D fabric. 400D-600D is kind of a standard backpack weight, probably what your school backpack was made out of growing up. Ultralight backpacking packs often range from 100D-210D. 70D and below are often tent or jacket weight fabrics.
Fabric weight is sometimes used in place of denier on spec sheets. Fabric weight is often quoted in oz/yd2. For reference, 1000D nylon is often around 11oz/yd2, 400D-600D is often about 6-8oz/yd2, 70D is often about 1.9oz/yd2 and 30d is often about 1.1ozyd2.
Cordura is a popular, industry leading fabric manufacturer. They make LOTs of different types of fabric, but many people use “Cordura” to refer to any 1000D nylon, or more specifically Cordura Brand’s 1000D nylon. It’s the same brand name vs product descriptor misuse that happens with Band-Aid and Kleenex. When you see the Cordura brand on a spec sheet, it’s an indicator of quality.
Fabric construction and weave – Most outdoor fabrics are made from synthetic(plastic) yarns woven together. Generally, the plastic is extruded into a very thin filament and multiple filaments are then spun into yarns which are then woven together to create fabric which then undergoes various finishing procedures. In a typical weave yarns run in two directions (at 90 degrees to each other) and are interlocked in an over/under pattern. A ripstop weave is common in outdoor fabrics. In ripstop fabric a heavier and tougher yarn is interspersed into the weave every so often. The purpose is to create a grid in the fabric that is tougher than the surrounding yarns and will stop tears. This is a way to create a fabric that is lightweight but still has a decent functional tear strength.
Uncoated fabric is breathable but not waterproof and is what your backpack liner, down jacket, tent side-walls, sleeping bag shell etc. is likely made from.
is waterproof, but usually not breathable. There are three popular ways to make a fabric waterproof (waterproof means highly water resistant in this case
PU or polyurethane is a spray on coating applied to the backside of the fabric at the mill and is the most popular way to waterproof a fabric. PU coatings are often tacky and have a rubbery feel. These types of coatings can eventually fail by delamination due to exposure to moisture or heat. Most PU coatings weaken the fabric, though Matador will soon be releasing products which use a UTS(Ultra Tear Strength) coating that actually increases tear strength.
Silicone is another popular way to make a fabric waterproof. “Silnylon” feels slick and almost oily to the touch. Silicone coatings are typically used on lighter weight fabrics and while they actually increase the tear strength of a fabric, some silnylons are known for “misting” through in heavy downpours. Some fabrics have both PU and Silicone coatings. To tell one from the other, pinch the fabric between your fingers and rub together... a PU coating is often so tacky that the fabric won’t slide as you move your fingers, but will instead stick to itself, a silicone coated fabric will be very slippery and feel almost frictionless.
Waterproof breathable (WP/B) fabric is another category. Gore-Tex is the most popular brand of WP/B fabric. Unlike the spray on PU or Silicone coatings, WP/B fabrics are typically constructed from a woven fabric laminated to a membrane. The membrane is basically a plastic layer with holes that are large enough for water vapor to pass though, but too small for liquid water to pass though. This fabric is often used in hardshell jackets to allow moisture from perspiration pass though without letting rainwater in.
DWR stands for durable water repellant. It is applied to the outer “face” fabric and causes water to bead up and slough off the fabric instead of getting absorbed. DWR is composed of microscopic “hairs” that stand off the fabric and create a hydrophobic effect. This coating will degrade over time with regular use as these hairs become matted down. DWR can be reapplied by the consumer at home, or often partially revived with a quick ride in the dryer at low heat. It doesn’t do the hard work of waterproofing -- that is the job of the PU, Silicone or WP/B Membrane -- but rather DWR works as a secondary mechanism that can help the face fabric from getting saturated. If your DWR fails, your garment will feel waterlogged, though the primary waterproofing mechanism(if there is one) should still keep liquid water from passing though your fabric.
Polyester vs Nylon – In general, nylon is stronger and softer than polyester. Polyester has better UV resistance than nylon. Nylon gets a stretchy, saggy feel when it gets wet, polyester doesn’t. Polyester dyes easier and produces more vibrant colors, but hold onto smells and can get stinky with body odor. In part because of its price tag, nylon is perceived as a more high end product than polyester, though both are well suited for outdoor fabrics applications.
Types of nylon – Not all nylons are created equal. Nylon can be made with slightly differing molecular compositions, which give the fabrics different properties. The most commonly used is Nylon 6, which, while still stronger than polyester, has a relatively low tear strength. Nylon 6,6 is the cream of the crop with the highest tenacity of commonly used nylons.
Robic is a proprietary formulation of Nylon which has a higher tenacity, or tear strength, than Nylon 6.
UHMWPE, Dyneema, DCF, Cuben Fiber – Recently a new kind of plastic has hit the fabric market… UHMWPE or Ultra high molecular weight polyethylene. These fibers have a strength-to-weight ratio many times greater than steel and are used in the construction of some modern bulletproof vests. Dyneema and Specta are brands that manufacture UHMPE. DCF – which used to be called Cuben Fiber -- stands for Dyneema Composite Fabric and refers to a specific family of fabrics. This is a nonwoven array of Dyneema yarns arranged at 90 degrees to each other and most often laminated to lightweight plastic film or woven polyester. Among outdoor fabrics DCF fabric has and unprecedented tensile strength to weight ratio. Many companies also make a woven nylon fabric that has a ripstop grid of (usually white in color) UHMWPE yarns.
Spandex, Lycra, Elastane – are functionally interchangeable terms and are added to yarns to make the resulting fabric stretchy. Lycra is in everything from base layers, to water bottle pockets. In outdoor fabrics, Lycra typically makes up only a small percentage of the fabric composition. As a rule of thumb the higher the percentage of Lycra in a fabric, the more stretchy the fabric.