How To Buy a Shell

Your ski shell is your skin when you’re out­side in the win­ter. It’s cru­cial for tem­per­a­ture reg­u­la­tion, weath­er pro­tec­tion, com­fort, and gen­er­al hap­pi­ness. And just like your skin, it should shed water, breathe, and fit you just right.

Types/Best Use: Ski shells, the weath­er-resis­tant out­er lay­er that will be your best friend in the win­ter, come in two types: hard and soft, which suit dif­fer­ent cli­mates and dif­fer­ent types of skiers.

Hard Shell: Hard shells are water­proof, breath­able jack­ets with lam­i­nat­ed mem­branes built inside the fab­ric. They’re prob­a­bly what comes to mind when you pic­ture a ski coat, but fab­ric tech­nol­o­gy, and how hard shells are built, has changed a lot in recent years. Hard shells work well in a range of weath­er con­di­tions, but they shine when it’s stormy.  They’re typ­i­cal­ly more expen­sive than soft shells.

Soft Shell: Stretchy, breath­able soft shells are built using a tight­ly woven face fab­ric and a wick­ing inner fab­ric. They’re wind resis­tant and high­ly breath­able, but often not water­proof. They’re good for ski­ing in cli­mates like Col­orado, where it’s pre­dom­i­nant­ly dry, or if you’re some­one who is high­ly aer­o­bic (or just plain sweaty). Com­mon soft shell mate­ri­als include Polartec Pow­er Shield® Pro and Schoeller Dryskin.


Con­struc­tion: Shells are built using 2‑, 2.5‑, or 3‑layer con­struc­tion, all of which involve a face fab­ric, a mem­brane, and some sort of lin­er. Some brands, like Patag­o­nia or Moun­tain Hard­wear have pro­pri­etary fab­ric like H2No® or DryQ Elite, while oth­ers con­struct their shells out of mate­r­i­al made by a fab­ric com­pa­ny, like eVent or GORE-TEX®.

2‑Layer Shells: 2‑layer shells have a water­proof, breath­able mem­brane bond­ed to the out­er face fab­ric. Inside of that they have a detached, hang­ing inner lin­er, often made of mesh, that pro­tects the mem­brane from oils from your skin, and from wear. Even though there are three parts, they’re con­sid­ered 2‑layer, because the lin­ing isn’t bond­ed to the face fab­ric. They’re typ­i­cal­ly cheap­er than 3‑layer shells, but they’re bulki­er, less breath­able, and heav­ier, too.

2.5‑Layer Shells: Your light­est option for a shell, 2.5‑layer shells are made of a face fab­ric, with a bond­ed mem­brane, and an inner coat­ing (the .5 lat­er) that helps pro­tect the mem­brane from abra­sion and the oils and gunk from your body. That inner lay­er, which often just looks like a raised pat­tern on the inside of the jack­et, pro­vides a light­weight bar­ri­er, but it’s often not as durable as a 3‑layer shell

3‑Layer Shells: The burli­est of the shells, 3‑layer jack­ets con­sist of a mem­brane bond­ed between a face fab­ric and a lin­er fab­ric. The lin­er is sealed to the inside of the mem­brane, pro­tect­ing it, and also cut­ting down on bulk and weight. The lin­ing dis­pers­es mois­ture, which is why 3‑layer shells tend to feel less clam­my, and guards the mem­brane from any­thing that might dam­age its func­tion­al­i­ty. 3‑layer shells are usu­al­ly the most expen­sive.


Face Fab­ric: The face fab­ric, which is usu­al­ly a vari­a­tion of tight­ly woven nylon or poly­ester, is there to pro­tect the del­i­cate mem­brane from out­side abra­sion and weath­er. The face fab­ric can have a big impact on the weight of the gar­ment.

Mem­brane: Mem­branes are the shell’s pores. They dif­fuse inter­nal mois­ture, and keep exter­nal mois­ture out. The holes in the mem­brane have to be big enough to let water vapor out, but small enough to pre­vent liq­uid water from seep­ing in. They’re typ­i­cal­ly made of Teflon, or polyurethane, which form a micro­scop­ic web with vapor sized holes.

Lin­ing Fab­ric: This is where most of your price and weight vari­abil­i­ty are going to come from. They range from cheap, brushed mesh in a 2‑layer shell, to soft, knit poly­ester back­ing in the 3‑layer shell.

Waterproof/Breathability: A water­proof, breath­able jack­et is the holy grail of ski shells, and fab­ric com­pa­nies like GORE-Tex and Polartec have invest­ed a lot of time and mon­ey mak­ing fab­ric that has both of those prop­er­ties.

Water­proof­ing comes from the mem­brane in the fab­ric, and/or from a coat­ing that’s applied to the out­side of the fab­ric, both of which inhib­it breatha­bil­i­ty. A fabric’s water resis­tance is mea­sured in mil­lime­ters of water it will hold before it leaks, so a jack­et that’s rat­ed 20k water­proof was test­ed to hold 20,000 mm of water over one square inch of fab­ric with­out leak­ing. Breatha­bil­i­ty, or how much water is evap­o­rat­ed from the inside of the jack­et to the out­side, is mea­sured by how many grams of water get pulled through the fab­ric in 24 hours. For instance fab­rics rat­ed as 20k water­proof, evap­o­rat­ed 20,000 grams. Fab­rics will be labeled based on their waterproof/breathability ratio, so a jack­et that says it’s 20K/20K is water­proof to 20,000mm and breath­able at 20,000 grams

DWR Coat­ing: Most shells are treat­ed with an exter­nal Durable Water Repel­lent (DWR) coat­ing to up their water­proof fac­tor. It will wear off with use and wash­ings, but you can re-treat you jack­et with a DWR prod­uct like Nikwax to give it new life.

Insu­la­tion: Soft shell jack­ets are rarely insu­lat­ed, but hard shell jack­ets some­times have an added inner lay­er for insu­la­tion. That lay­er will be made of down, syn­thet­ic insu­la­tion, like Pri­maloft or fleece. Insu­la­tion ups the warmth, but increas­es the weight, and decreas­es the ver­sa­til­i­ty of a jack­et.

Hood: there are three main styles of hoods: built in, detach­able, and roll­away, which fold up in the col­lar of your jack­et. Detach­able and roll­away hoods, which give you the option to go hood­less, also add bulk and weight around the neck, and add a poten­tial­ly leaky seam in an area that gets a lot of expo­sure.

Pock­ets: What you need to access quick­ly will define what you should look for in terms of pock­ets. Some shells have media and pass pock­ets, which are con­ve­nient for resort days, but unnec­es­sary for back­coun­try ski­ing. In a jack­et that you’re wear­ing in the back­coun­try, look for pock­ets that you can access with your pack on, and ones that are big enough to stash skins or acces­sories like gog­gles and gloves on the fly.

Seams: In a water­proof shell, the seams and zip­pers have the biggest poten­tial to leak, because they’re essen­tial­ly a bunch of tiny holes in the fab­ric. There are three ways that seams are made water­proof: they’re sealed, either ful­ly or crit­i­cal­ly, by seal­ing water­proof fab­ric over the edges of the seams. Ful­ly taped shells have all of the seams sealed, which crit­i­cal­ly taped ones only have it on the seams that are most exposed to mois­ture.  The third option is weld­ed seams, where instead of being sewn togeth­er, the seams are heat bond­ed. Weld­ed seams are lighter and more ful­ly water­proof, but a jack­et with weld­ed seams will be more expen­sive.

Weight: The weight of the shell depends on the con­struc­tion, the fab­ric, and the added details, like Lost weight often comes from the details: weld­ed seams, min­i­mal­ist zip­pers, and sewn-in hoods all cut weight, but can make a jack­et more expen­sive.

Back Length: Your jack­et should be a lit­tle longer in back, so it doesn’t gap when you crunch up into an ath­let­ic stance. The extra length will keep snow and rain out, too.

Pow­der Skirt: Pow­der skirts keep snow from get­ting up your jack­et and down your pants. They’re often detach­able, so if you don’t like the con­stric­tion of an attached pow­der skirt you can zip it out.