Alpine Touring Last Chance Sale | AT Skis w Bindings | AT Bindings | AT Boots | Climbing Skins

Powder7 Logo

Waterproof Ratings and Breathability for Ski Jackets and Pants

Shop our selection of outerwear.

When you're out in the mountains, nothing can ruin your day faster than getting cold and wet. That's where proper outerwear proves essential. But what's the deal with all the different specifications? One jacket is rated 10k/10k, another 20,, ummm, what does that even mean?

For a full waterproof and breathability rating breakdown, take it from Powder7's apparel expert:

Waterproof/Breathability Ratings

Waterproof Ratings: Standard laboratory testing for waterproofing measures how much liquid (water, snow, rain, sleet, beer) in mm, that can be suspended in a 1-inch square tube before liquid starts to seep through the fabric. This tests both general water repellency as well as performance under pressure. Higher numbers mean more water resistant fabric. A fabric rated 20k for waterproofness resists approximately 66 feet of liquid stacked up in that 1-inch square tube before any seepage begins. Burly.

Breathability Ratings: Standard laboratory testing for breathability measures the amount of water vapor (your sweat from vigorously enjoying your time spent outdoors) in grams, that will pass through one square meter of the fabric in 24 hours. Higher numbers indicate a more breathable fabric. For example, a solid rubber or vinyl suit may be completely waterproof, but it will have zero breathability, so you'll end up soaked from your own sweat and, when you stop exerting yourself, you'll start to get cold. Bummer.

Let's Break It Down
Waterproof/Breathability RatingSo...what is that good for?Performs in what conditions?
0 to 5,000 mmNot much in terms of inclement weather.Light drizzle, dry snow, bluebird days.
10,000 mmPlaying outdoors in places that usually see drier snow--Colorado, Utah, etc. Light aerobic activities like lift-accessed skiing.Average rain and snow. Lower pressure.
20,000 mm and upPlaying outdoors in more extreme conditions and in places that see heavy rain or heavier, wet snow--Pacific Northwest, New England, etc. Strenuous aerobic activities like touring/hiking.Heavy, prolonged rain or heavy, wet snow. Higher pressure.

DWR, 2-Layer, and 3-Layer Fabrics

DWR: Garments treated with a DWR coating have a Durable Water Repellent coating that helps water bead up on the fabric's surface. This coating will eventually wear out. You can re-treat garments with specialty products to help restore the DWR coating, but true waterproof breathability comes from a technical fabric's membrane, not the DWR coating. DWR coatings are great, but garments with waterproof breathable membranes are typically superior.

2-Layer Fabric: 2-Layer garments have a waterproof/breathable membrane laminated to the face fabric (the fabric you see on the outside of the jacket). 2-Layer fabrics typically have a mesh liner hanging on the inside of the garment to keep your skin away from the membrane. These fabrics are usually more waterproof and breathable than garments only treated with DWR, but are not as waterproof and breathable as 3-Layer fabrics.

3-Layer Fabric: 3-Layer garments have a waterproof breathable membrane laminated between the face fabric (what you see on the outside of the jacket) and the backing fabric (what you see on the inside of the jacket). The backing fabric on a 3-Layer shell does not hang loosely like you will see in a 2-Layer garment. 3-Layer construction is the most durable and best-performing construction for waterproof breathability.

Waterproof Zippers and Seams

When making performance outerwear, sewing machines make a lot of small holes in the fabric, holes through which moisture can potentially get in to ruin your day. Another area for potential water penetration is the zipper. Manufacturers solve these potential problems in a number of ways.

Seam Taping/Seam Sealing: Waterproof tape is applied along every seam that fully seals any holes made during the garment's production, maintaining waterproof breathability. A "critically taped" garment is only taped on high-exposure seams like the shoulders, hood, neck, and chest. A "fully taped" garment is taped on every single seam.

Welded Seams: To avoid the problem of putting holes in the garments in the first place, some manufacturers weld their garments' seams using glue, also maintaining waterproof breathability. Many welded seams are also seam taped.

Waterproof Zippers: Standard zippers are not waterproof. Be sure your outerwear zippers are waterproof if you plan to explore the outdoors in heavy rain or snow. Most garments rated at 20k feature waterproof zippers. Other garments offer a "storm flap" to cover the zipper and, in effect, making them waterproof.

Pretty simple, right? You can see our full selection of outerwear here. If you have any questions about clothing you see on our website, just give us a call at 303-237-7547.

This content is copyright of Powder7 and cannot be reproduced.