The Specter LT Hoodie
The Specter LT Hoodie (courtesy, Westcomb)
Gear Guy

What’s the deal with all the different kinds of waterproof/breathable jacket fabrics?

The big breathability issue is making buying a jacket confusing. eVent has thrown a cat ong the pigeons and waterproof soft shells also change my options. Is there any clear thinking on this subject? I have the new Aegis jacket and that's just a proprietary fabric but seems to work fine. In other words, what are the "real" facts and how do you choose the "best" jacket for various applications? Ian South Africa

The Specter LT Hoodie

That’s a tough question, Ian. All the big waterproof/breathable fabric makers have done reams of studies trying to show theirs is “best.” But there are so many variables, it’s tough to say what jacket will work best on a given day, let alone on a regular basis. What is the temperature? The humidity? Is it raining hard or drizzling? For how long? Are you active or sitting still? And on and on…

The Specter LT Hoodie The Specter LT Hoodie

Strictly anecdotally, eVent works very well…for me. It’s a material that is chemically similar to the PTFE in Gore-Tex, but that has a “secret sauce” that makes it more breathable (or so say the eVent folks). But it’s hard to find. British Columbia’s Westcomb makes some lovely pieces that use eVent. The Specter LT Jacket ($300) is a cleanly designed, all-purpose jacket that weighs a mere 12 ounces. Westcomb also does some innovative things like combining eVent with fabrics from Polartec and other makers, so you get a mix of hard shell and soft shell properties. The HX Flex Jacket ($350) has eVent on the shoulders and arms to shed rain, and Polartec Powershield around the torso. That’s a pretty potent mix of breathability, waterproofness, and stretchiness.

That said, Gore-Tex’s relatively new Pro Shell material is, in my experience, on par with eVent in all the important attributes. It reaches its ultimate expression in Mountain Hardwear’s Argon Jacket ($450). Yes, that IS a lot of money.

Then we have the Aegis, by which I think you mean the Marmot Aegis ($140). It uses a proprietary fabric called MemBrain that is designed to react to body heat—when you’re cool, the pores in the fabric close up, and when you’re active, they open so water vapor can escape. I haven’t used a MemBrain jacket for several years, but the stuff does seem pretty effective. The Aegis also has so-called “2.5-layer” construction, meaning it has a two-ply laminate, with an inner half-layer of tiny dots that hold the fabric a little bit away from the body and that helps reduce any clamminess.

Waterproof soft shells I don’t understand. Some makers take a waterproof/breathable shell, add a very light layer of insulation to it, and call it a “soft shell.” To me that just creates a really warm rain jacket, which maybe we don’t really want. I prefer soft shells that don’t pretend to be fully waterproof, but that breathe really well and act on their own as light insulation.

From Outside Magazine, April/May 2021
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Lead Photo: courtesy, Westcomb