gore-texGore-Tex, we’ve all heard of it, but what exactly is it, and do we really need it? It has become almost a generic term for a line of advanced technology fabric systems, that when it comes to ski jackets and pants, is one reason why shells” are now so popular. Because of materials like Gore-Tex, layering, or the ability to add or shed inner layers, translates to all day comfort. Since the outer shell is your first line of defense, it only makes sense to choose something that will not only keep you warm, but also cool. Thankfully, some relatively new high-tech fabrics known as microporous membranes provide just the solution.

Gore-Tex is the original and most established brand of microporous membrane fabrics. Since its patent ran out, there are now a slew of imitators, but the term Gore-Tex has become almost a generic term for all these MMFs. So whether it’s eVent, Intuitive, H2NO, HyVent, Polartec NeoShell, or others, they all share variations of the same basic technology providing a breathable, waterproof, and windproof fabric.

Goretex schematicThe Membrane: The PTFE membrane is the heart of all Gore-Tex products. It contains over 9 billion microscopic pores per square inch. These pores are thousands of times smaller than a water droplet, yet thousands of times larger than a water vapor molecule. This makes the membrane waterproof from the outside, while allowing perspiration to escape from the inside.

These fabrics come in varying degrees of waterproofness & breathability effectiveness. This is expressed in terms of how many millimeters of water in a 1″ column a fabric can repel before it starts to leak and by how many grams of water vapor can escape over a 24-hour period. The best fabrics are generally rated around 20,000mm/20,000g which would be expressed as “20k/20k”.

The Laminate: The laminate is the membrane bonded with the main body synthetic fabric. It is laminated to either one or two surfaces, being described as two or three-ply (2L or 3L). Three-ply is warmer and more durable, while two-ply is softer and lighter.

The terms hard shell and soft shell, when referring to outerwear, are just as they sound. It is how they feel to the touch and may or may not be MMF fabrics. In the case of Gore-Tex, the softer feeling fabrics would likely be 2L (possibly 3L), while the stiffer fabrics are 3L. In a serious mountain/backcountry shop, a soft shell does not have a membrane (is not waterproof) and a Gore style soft shell is now referred to as a “stretch hardshell”.

Sealed Seams: Sealed seams are used to offer complete weatherproofing. A special tape system is used to seal off the holes created when the garment has been stitched during manufacturing.

Durable Water Repellent (DWR): Gore-Tex fabrics designed for use in the outdoors are also coated with a surface treatment at the final stage of manufacturing. This DWR treatment is used to keep the breathable pore based fabric free from beads of moisture and rain, allowing them to fall away.

The DWR typically has a shorter life span, so while the pore construction of the fabric is still working, you may notice leaks and seeping of moisture. When the face fabric eventually becomes soaked due to an absence of DWR, there is no breathability and sweat will cause condensation to form inside the jacket. This may give the appearance that a jacket is leaking when it is not. The DWR can be reinvigorated by tumble drying the garment, ironing on a low setting, or you may need to retreat the item in order to reestablish its water repellency. To retreat a Gore-Tex product, simply wash it and then apply a reproofer, which can be a wash-in or spray-on product. NikWax makes a nice line of such products.

The outdoor fabric industry is currently experiencing a surge in new product development that competes directly with GORE-TEX®.The technology of these fabrics continues to advance and not all of the waterproof breathable laminates on the market are built like GoreTex. In fact, most of them are built differently. Some share the ePTFE membane element and some go with the solid polyU membrane. Products like eVent™, Polartec® Neoshell®, Omni-Tech, Conduit, and Dri.Q Elite are all extremely waterproof and push the envelope on breathability. Use of very thin Polyurethane and Polyester membranes is also expanding, with much of the innovation coming from Asia – these fabrics have the advantage of not requiring a separate layer to protect the ePTFE membrane from contamination, and are catching up in the breathability department.

Examples of Waterproof/Breathabilty Ratings for some of the major manufacturers:

Brand Fabric Waterproofness (mm/24) Breathability (gr /24)
Columbia Sportswear Omni-Tech® 10,000 10,000
Flylow Gear Intuitive 3-Layer 20,000 20,000
Event Event 30,000 22,000
Gore-Tex® PacLite® 28,000 15,000
Gore-Tex® Pro-Shell 2-Layer 28,000 25,000
Gore-Tex® Pro-Shell 3-Layer 28,000 25,000
Lowe Alpine Triple Point 3-L 20,000 20,000
Marmot MemBrain® 20,000 25,000
Marmot PreCip® 15,000 12,000
Marmot PreCip Plus® 25,000 15,000
Mountain Hardwear Conduit 20,000 20,000
Sierra Designs Hurricane 8,000 2,000

As you can see, the technology is quite complex and there are many different variations and approaches to achieving a high performance microporous membrane fabric. Add to this the fact that testing is generally done independently and lacks any real standardization. Also many other factors involving how different materials interact in combination with one another will have a dramatic effect on the true and perceived overall performance of any given MMF garment.

Flylow Higgins Jacket

Flylow Higgins Jacket

So what should you choose? Given performance versus price, what do you really need? Generally speaking, most resort skiers would find garments with a 10k/10k, 2L fabric more than sufficient and reasonably priced, while the more serious demands of backcountry riding may warrant the additional expense of a 3L, 20k/20k offering. Unfortunately, not all manufacturers explicitly provide these specifics on the label, but any good shop should be able to provide them, and you should know what you are paying for. So stick with a reputable brand, ask questions, and check product reviews on great resources like EpicSki’s Gear Reviews.

For a complete lineup of clothing engineered specifically for the rigorous demands of backcountry riding and inbounds hard-charging, check out the stoke from Flylow Gear. If you’re in the Phoenix area, go by any one of the three SkiPro Ride Shop locations and hit them up for more expert advice.For more good stuff, please stay connected to the DSJ rider network by joining us on meetup.com/DESERTSNOWJUNKIES and “like” us on facebook.com/#!/DesertSnowJunkies.