Gear Made Clear: Outerwear

A lot of people think they need to buy the warmest outerwear possible, but the key to comfort is actually temperature regulation. If you overheat, you sweat, and when that sweat gets trapped inside your jacket, it will eventually make you cold.

Your primary focus should be waterproofing and breathability, and you should think of your outerwear not as the only apparel choice you need to make but as the outermost part of your entire layering setup—a modular system, with pieces that can be added and removed as the weather fluctuates. With that said, let’s break down some of the technical info that will help you choose the outerwear that’s best for you.

Fun fact: Overheating from poor apparel choices is also what leads to foggy goggles.

Waterproof Membranes
Modern ski outerwear is built using highly technical fabrics. At the heart of them is a waterproof membrane. The magic in these membranes is that they have tiny pores that are too small for water droplets to get inside the shell (waterproof), but large enough for water vapor (sweat) to escape from inside the garment (breathable).

Waterproof & Breathability Ratings
When you see ratings associated with a technical piece of outerwear, the numbers are referring specifically to the membrane. The waterproof rating is derived from a test in which a column is placed on top of the membrane and water is gradually added inside until it leaks through. The measurement will be something like 5,000 mm, 10,000 mm, or 20,000 mm.

Breathability is tested by creating a humid environment on one side of the membrane and measuring how many grams of water vapor pass through the fabric over 24 hours—usually 5,000 g, 10,000 g, or 20,000 g. Ratings are typically presented with waterproofing first, followed by breathability (20k/20k). The higher the numbers, the better the performance. For these membranes to work efficiently, they must stay clean and dry, and to this end, they are protected by face fabrics and liners on both sides.

Image: Andrew Maguire

Insulation Types and Performance
If you're purchasing an insulated jacket, be sure to check the type and amount of insulation used. Generally, there are two types of insulation: down and synthetic. The amount of each is measured by a “fill” rating—the higher the number, the warmer the jacket is designed to be.

Down is known for its incredible warmth-to-weight ratio and comes from animals like geese and ducks, which makes it more expensive. It’s worth noting that down does not perform well when it gets wet—it compacts and loses all of its warmth. Synthetic insulation is cheaper and more versatile but requires more volume to replace the warming power of down loft. It will, however, retain its warmth when things get soggy.

Two-Layer (2L) vs. Three-Layer (3L) Construction
When choosing a new jacket and pant, the first decision you’ll want to make is between two-layer and three-layer construction.

A two-layer garment features a face fabric bonded to the outside of the membrane, along with a simple liner that protects the inside. This liner can also hold insulation. These pieces work great for resort skiing but aren’t as high-performance as three-layer shells.

Three-layer construction starts with a face fabric bonded to the outside of the membrane, but instead of a sewn liner, they have an inner layer bonded behind the membrane. These jackets are highly breathable, very low profile, and never insulated. While some people prefer insulated jackets for warmth, three-layer garments offer more versatility in any temperature and will keep you just as warm when combined with the right mid- and baselayers. This construction is ideal for backcountry pursuits, environments with large temperature fluctuations, or for skiers who easily overheat.

Durable Water Repellent (DWR)
Durable Water Repellent (DWR) is integral to the performance of your outerwear for two reasons. First, it repels water from the outer layer of your jacket or pant. Second, it keeps this layer dry so that the membrane underneath can perform as it needs to. If the face fabric soaks through, the membrane loses its breathability and crushes the performance you paid for.

Your outerwear should come with DWR on the face fabric, but these coatings break down over time and need to be reapplied. Regular washing and maintenance of your DWR will keep your jacket performing at its best.