A Snow Bunny's Guide to: Waterproofing
Hello again, snow bunny. Now that we’ve covered base layers, we should talk about outerwear. I would recommend that you get waterproof pants and jacket. Here in the Northwest, we’re notorious for having wet weather—even in the middle of the winter. I recommend making sure your pants and jacket are fully taped and seamed, not just critically. What does this mean?
If the seams on your outerwear are only critically taped, then this means that they are only taped where wetness will most likely contact, thereby rendering them not 100% waterproof. Fully taped seams mean just that—they’re completely taped, ensuring a fully waterproof garment.
Another feature you might want to consider is the waterproof rating of the garment. The most common ratings you’ll see are 5K, 10K and 20K. What do these represent? A 20K rating, sometimes also displayed as 20,000mm means that a jacket can withstand almost 66 feet of rain (or 20,000mm) in 24 hours before the person wearing the jacket gets wet. Though, again, make sure that the seams of that 20K jacket are fully taped. Otherwise that 20K rating makes the waterproofing of the jacket pretty much pointless.The 20K rating is a little extreme, though according to backcountry.com “A 20K jacket will keep you dry in nearly any condition. A manufacturer that bothers to make a jacket from 20K-rated fabric with a membrane is probably going to cover every seam and use waterproof zippers and storm flaps. I would feel confident in any coastal snowstorm in a 20K jacket.”
Though, remember 0K, 5K, 10K and 15K ratings also exist. So unless you plan to be pummeled by rain in a Typhoon or Hurricane, I would recommend a waterproof rating of at least 10K. 0K represents that it is able to withstand 0mm of rain, so obviously not waterproof. 5K represents water resistant or rain proof, but if there was any sort of pressure, you’d probably get wet. Additionally, a 5K jacket probably wouldn’t manage to keep you waterproof for an extended period of time. 5K is usually what you would expect for low end, cheaply manufactured ski and snowboard garments. You might also find a soft-shell jacket that has 5K waterproofing. This rating is more ideal for spring conditions. Do you research before you buy!
A 10K rating means it’s simply 5K doubled, so you might expect a more waterproof jacket. 15K + equals a garment that is totally waterproof, even under serious pressure. The Gore-Tex manufacturer usually makes garments with their product that has at least a 15K waterproof rating or higher.