What is the best fabric for a waterproof hiking jacket?
With so many technical terms (2-layer, 3-layer, proprietary membranes...), it's hard to know which fabric to choose for your next hiking jacket. Here's how to see things more clearly.
The most common technical membranes
The performance of a waterproof hiking jacket depends above all on its membrane, the technical layer that blocks water while letting sweat escape. Several technologies coexist on the market, with similar principles but different names depending on the brand (Gore-Tex being the best known, but far from the only one).
They all work on a similar principle: microscopic pores, smaller than a water droplet but larger than a water vapour molecule, which stop rain getting in while letting sweat out in the form of vapour.
2, 2.5 or 3-layer membranes: what's the difference?
- 2-layer: the membrane is backed by a separate inner lining. More affordable, but generally a little heavier and less breathable than the higher versions.
- 2.5-layer: a thin protective coating replaces the traditional lining, for a lighter overall garment, often preferred for lightweight hiking jackets or waterproof windbreakers.
- 3-layer: the membrane is laminated directly between the outer fabric and an inner protective layer, for the best durability and breathability — at a generally higher price.
How to choose according to your activity
For occasional hikes on easy terrain, a 2 or 2.5-layer jacket is more than enough, with good value for money. For regular use in more demanding conditions (sustained rain, prolonged effort), a 3-layer jacket will offer better comfort over time, particularly thanks to better sweat management.
The weight of the outer fabric matters too
Regardless of the membrane, the outer fabric (the "denier") affects abrasion resistance and the final weight of the jacket. A thinner fabric makes the jacket lighter but will stand up less well to repeated rubbing from a backpack, while a thicker fabric gains in durability what it loses in lightness.
Finally, whatever membrane you choose, remember to regularly reproof your jacket with a suitable water-repellent treatment: even the best fabric loses performance if its surface treatment wears off with washing and use.