Waterproof Rating and Breathability Explained

If you’re heading to the mountains then having waterproof gear is essential. Whether crushing it on the powder, hiking in the hills, or climbing the crag, the weather is always unpredictable, especially in the mountains. That's where our gear comes in.

Waterproof and breathable, our elite range of waterproof coats, ski jackets, and trousers will help keep you dry and comfortable wherever you choose to adventure in the outdoors. So, what is waterproofing, and what do the numbers really mean? Our experts give you the lowdown on everything you want and need to know about waterproofing and breathability in waterproof coats and trousers...

Waterproof fabrics are resistant to water penetration, achieved using a membrane or a coating that acts as a barrier, preventing moisture from permeating the fabric.

Breathable fabrics allow sweat in the form of water vapour to escape from the inside of the fabric to the outside. Breathable materials help keep you cool and dry, especially during high-exertion activities like snowsports, hiking, and climbing.

Whilst it is common for a fabric to be waterproof and breathable, some items may prioritise particular properties over others. Some materials may be more waterproof, and some fabrics may be more breathable. These variations in the fabrics help cater to the kind of activity you are embarking on.

There's no question. A waterproof and breathable snow jacket is essential gear for the slopes. But finding the right one for you isn't always so simple. Ensuring you get the right levels of waterproofness and breathability will make sure you stay comfortable during long days of intense shredding.

For more help buying the right ski jacket, check out our guide here.

Waterproof Ratings:

• 5,000mm: The minimum rating for a jacket to be called rainproof. However, it won’t stand up to much more than a light shower.

• 10,000mm – 15,000mm: Withstands most downpours and heavy snow, but will soak through over time if subjected to pressure, such as crashing in wet snow, kneeling, sitting down, or carrying a heavy pack.

• 20,000mm and Up: The rating you should look for if you're planning to be out in all conditions carrying a heavy load.

Breathability Ratings:

• 5,000 – 10,000g/m²: This level of breathability is fine for resort skiing, urban travel, or camping, but will get a bit clammy during high-intensity hiking or climbing.

• 10,000 – 15,000g/m²: Ideal for adventurous travel or backcountry skiing, but breaking trail through snow or straight uphill might prove too much.

• 15,000 – 20,000g/m² & above: An extended trip to the hills, trekking in warm climates or otherwise working hard and perspiring heavily.

No. The waterproof and breathability ratings you need will depend on the conditions and the activity that you are doing. For instance, if you are mainly a piste skier in dry conditions you can get away with a lower waterproof rating. If you are a back-country skier in wet conditions, you will need a high waterproof rating so you’re not soaked from snow, and a high breathability rating so you are not drenched in sweat.

Generally, a minimum of 5,000mm is good for skiing and snowboarding in cold but clear conditions, especially if you enjoy taking regular breaks. 5-10,000mm is ideal for those who spend long days on the mountain, in all weather conditions. 10-20,000mm is best for those in wetter climates or skiers and snowboarders who prefer backcountry.  

Although fabrics such as rubber and wax can be fully waterproof, outwear for active sports will usually be varying degrees of water-resistant, as with enough water, wear, and pressure - it will eventually leak. 

Your activewear must retain an element of breathability to allow wicked moisture to escape. As a result, most active sport clothing balances protection with breathability.  

•  Seam sealing: When clothes are sewn together the needle makes tiny holes, which water could leak through. To stop this from happening the seams are “taped over” with waterproof tape. They can be fully or critically taped, which means all the seams are taped or just the most exposed areas.
  
  
• DWR: Durable Water Repellent is usually applied to exterior fabrics for extra waterproofing. It may become less effective over time but remains still a useful feature to look for as it provides an additional layer of protection.
  
  
• Fabric care: Different membranes have different care instructions. Some membranes like GORE-TEX have easier care instructions, whereas others have more complicated procedures to maintain the waterproofing.
  
  
• Brand: There are many membranes, from GORE-TEX and eVent to brand-specific membranes by The North Face, and Helly Hansen. These membranes will be better for various activity types and have different testing standards. Generally, whilst both are waterproof and breathable GORE-TEX is warmer and easier to care for, whilst eVent is more breathable but will require more reproofing/maintenance. 

Depending on the weather conditions, activities you're pursuing, and personal preference - the right waterproof jacket for you will vary.

If you are doing a high aerobic activity, like climbing or running, you will want something more lightweight and breathable. Pertex Shield technology jackets are highly recommended for those looking for higher breathability ratings at a fraction of the weight.

If you need a good all-season all-rounder for activities like walking then a softshell will serve you well. Bridging the gap between fleeces and waterproof jackets, softshells offer water resistance, breathability, and warmth at a fraction of the weight. Whether you need a lightweight outer layer or a breathable mid-layer softshells are the perfect in-between for your outdoor adventures.

If you're outside in more extreme conditions, for instance, longer and more exposed hikes, then a hardshell with increased waterproof capabilities is your best bet. This will use a 3-layer construction with a durable face fabric able to withstand bad weather.