Though ‘waterproofing’ is a popular term to describe the level of performance of technical outerwear, only non-breathable membranes will provide true ‘waterproofing.’ All other outerwear is highly water ‘resistant.’ Water resistance is measured on a scale of mm. Standard outwear ratings range from 5,000mm to 20,000mm.
In the case of a 10K rated fabric, it would take 10,000mm of water within a 1 sq. inch cylinder over a piece of fabric for water to penetrate that fabric. The higher the number, the more water resistant the fabric. We start at 10K/5K across our line.
20K/10K – Wet Snow, Heavy Rain
10K/5K – Above Average Snowfall, Constant Rain
5K/5K – Dry Snow, Light Rain
600mm/600mm – Minimum to pass rain test
20K/10K+ -- Ultimate
20K/10K -- Premium
10K/5K -- Performance
(waterproof, waterproofing, rain, wet, snow, mm)