Waterproof and Breathability Explained
One of the most common technical features you will hear (or read) when shopping for ski and snowboard gear is waterproofing and breathability. In this guide we will explain what each are, how you measure them, and what these numbers mean for your gear’s performance.
Waterproof ratings are determined by the amount of water pressure that a product can withstand and is normally the first number quoted in a waterproof and breathability rating. E.g. 20K/10K means that the garment is 20K waterproof. But what does this mean?
You might wondering why garments aren't 100% waterproof? Well the truth is if it was completely waterproof, we would be sweating bullets because your garment won’t be able to breathe. This is why the membrane is so important as it’s designed to stop water entering from the outside but still allow body vapour and perspiration to pass through the fabric, kind of like a one-way door.
Breathability basically refers to "moisture wicking" in which the body vapour and perspiration passes through the fabric and is normally the second number quoted in a waterproof and breathability rating. E.g. 20K/10K means that the garment is 10K breathable. But what does this mean?
There are many different tests to determine how breathable a garment is, and these tests measure how much vapour and perspiration can be released from inside a garment to outside. The number the test produces e.g. 10k breathability, means that during a typical 24-hour period 10,000grams of vapour and/or perspiration will be transferred through the fabric. Like waterproof ratings the higher the breathability number the more breathable a garment is.
Hopefully we've helped you better understand two of the most common rating systems you will find on snow gear. See you on the slopes!