When hiking, especially in the mountains, the weather is often unpredictable. You need to dress accordingly by choosing clothing that adapts to the elements. To face bad weather, it's important to have waterproof clothing. The choice of this type of clothing will depend on the weather, the temperature, the intensity of effort, the type of hiking and the outdoor environment. Explore more about waterproofing in hiking clothing.
The difference between water repellency and waterproofing
Water-resistant hiking clothing can be either water-repellent or waterproof. It's worth knowing the difference between these two properties before choosing your garments.
Water repellency is the ability of a fabric to cause water to bead and run off its surface. This prevents it from absorbing water and becoming heavy. However, a water-repellent garment cannot withstand prolonged heavy rain — its capabilities are limited. It also needs to be treated regularly to maintain its water-repellent properties. You can wear water-repellent clothing for short hiking trips or when there is little chance of encountering a shower.
Waterproofing is the ability of a fabric to prevent water from penetrating. It can absorb water, but won't let it pass through the garment. A waterproof jacket has millions of pores, designed to be smaller than water droplets so they cannot pass through. Waterproof hiking garments are designed to allow good breathability — an essential characteristic for the activity. It's better to choose a waterproof jacket over a rain garment such as an oilskin, which is not breathable at all.
Choosing a waterproof and durable membrane
Waterproof fabrics are achieved through the use of a membrane. Membranes today are extremely sophisticated. They are designed to contain millions of microscopic pores per cm². The pores must be large enough for water vapour from perspiration to escape, while being small enough to keep rain out. A jacket or trouser fitted with a good membrane is both waterproof and breathable.
Waterproof jackets were revolutionised by the arrival of Gore-Tex® technology in 1970. Gore-Tex® products were the first to successfully combine waterproofing, windproof protection and breathability. Today, the brand remains the benchmark for waterproof clothing. Many outdoor brands have also developed their own technologies similar to Gore-Tex®. You can choose clothing fitted with OutDry™ membranes for Columbia, FuturLight™ for The North Face, or the Ultrashell® designed by Cimalp. The latter guarantees waterproofing of 80,000 MVP and a rating of 20,000 Schmerber. It goes with you on every adventure, without compromise.
Measuring the waterproofing of hiking clothing
To measure the waterproofing of hiking clothing, various tests are carried out. The most well-known and widely used is the hydrostatic head test. It involves placing the fabric under a column of water and determining at what point droplets begin to pass through. The higher the column, the more waterproof the fabric is considered to be. The unit used to measure fabric waterproofing is the Schmerber. One Schmerber equals a water column height of 1 mm. While waterproofing is highly effective at 10,000 mm, a garment is considered fully waterproof from 20,000 mm.
The waterproofing rating can be found in the technical specifications of a hiking garment:
- 2,000 mm: The fabric is resistant to light rain. This level of protection is sufficient for a day out if you don't expect to face heavy rain.
- 10,000 mm: The garment is waterproof. It is suitable for hiking in mid-mountain terrain, coastal environments or a trekking trip of a few days.
- 20,000 mm: The fabric is fully waterproof. You can wear it to face all kinds of severe mountain weather: gusts of wind, freezing rain and snow.
- 30,000 mm: These garments are reserved for extreme conditions and are very rarely found.
When hiking, it's important to wear weather-resistant clothing. You can choose your hiking jacket or trousers and their waterproofing rating based on the type of hiking you do. Investing in waterproof and breathable clothing allows you to hike in comfort, whatever the conditions.
