Stretch-woven soft shell fabrics are the best choice for all-purpose cold weather shells.
This is the sixth in a series of articles outlining a simple clothing system for outdoor recreation. An overview of the system is offered here. Topics covered include baselayers, lightweight fleece insulation, midweight insulating jackets and wind shells.
When I started working in the outdoor biz back in 1991, there was an idea going around that you could have one waterproof/breathable shell jacket that would work for all conditions. After years of development, Gore-Tex fabric had become breathable enough and waterproof enough that it seemed like it might be possible to use a single Gore-Tex shell instead of carrying both a mountaineering parka and a waterproof shell on backcountry trips.
Up until this time, waterproof clothing had generally been considered a specialty item in a layering system–a last resort if it was pouring down rain. The lack of vapor transmission through traditional waterproof jackets meant that under high exertion perspiration would build up inside the shell and soak insulation layers. Waterproof/breathable fabrics promised to eliminate this problem and reduce pack weight for outdoor enthusiasts.
Most of us who came up in the outdoor industry at the time fully adopted the Gore-Tex shell fabric concept and did our winter adventuring in waterproof/breathable shells. Looking back, they never did seem to work as well as advertised. Under ideal conditions with the correct temperature, humidity and exertion level, waterproof/breathable fabrics can effectively pass water vapor from inside to outside the shell fabric. Unfortunately, conditions are seldom ideal in the outdoors.
The biggest problem for most folks is that waterproof/breathable fabrics simply don’t breathe well enough to keep up with perspiration during high exertion activities. Anyone who has taken a rainy, warm weather hike in a waterproof/breathable raincoat knows this well enough. Anyone who has sweltered away in Gore-Tex bibs on a ski tour knows it too. In the cold, waterproof/breathable shells frost up. In the warm, they sweat up. In reality, waterproof/breathable shells don’t breathe well enough to function as a single, multipurpose shell layer.
Twenty five years later this seems like common sense. Back then it didn’t. Our clothing systems consisted of a polyester baselayer, Polartec fleece insulation and a Gore-Tex shell, and we figured that was the best system available. The US Army developed its Extended Cold Weather Clothing System (ECWCS) around this time and fielded something very similar, with Gore-Tex shells as an outer layer to be used in all conditions. It wasn’t until soldiers deployed to the mountains of Afghanistan following the 9-11 attacks that the limitations of this system were demonstrated. Special operations personnel were struggling to stay warm in their issued gear and put in a request to the US Army R&D center to come up with a better solution. This kicked off the development of the Protective Combat Uniform (PCU) in the early 2000’s.
The development of the PCU is discussed in the opening article of this series. In summary, the PCU replaced the waterproof/breathable Gore-Tex outer shell of ECWCS Gen II with a fully breathable, air-permeable soft shell top and bottom. These soft shells were to be used in all cold weather conditions except for sedentary activities in prolonged rain.
Soft shell technology came into the public eye in the US toward the end of the 1990s. Stretch woven fabrics had been in use in Europe before then, but they really came onto the scene in the US when Patagonia rolled out its Regulator layering system in the early 2000’s I first saw the label “soft shell” used in a Patagonia catalog around that time. The term referred to the stretchy, soft fabric used in these garments and served to differentiate them from waterproof/breathable shells, which were subsequently labeled as “hard shells”. Soft shells are stretchy, air permeable and water resistant. Hard shells are windproof, waterproof and minimally breathable.
The idea behind a layering system topped with a soft shell is simple. If you are exerting yourself in inclement weather you are going to be wet one way or the other. If you’re going to be wet you may as well be as comfortable as possible. Breathable hard shells trap moisture inside the layering system and make it much more difficult to dry your insulating layers with your body heat. Soft shells don’t provide much protection from the rain but they breathe so well that you can walk yourself dry once the precipitation stops. In the vast majority of cold weather conditions a person will be much more comfortable in a soft shell than a hard shell.
How it Works
As mentioned above, soft shell fabrics are air permeable. They are wind resistant because of their tight weave but lack a semi-permeable membrane that would make them wind PROOF. The wind will penetrate a soft shell a little bit. This is a feature not a bug.
Soft shells offer plenty of wind resistance. The small amount of air that does pass through them in windy conditions helps to dry your insulating layers. As your body heat drives perspiration away from your baselayer and into your insulating layers, a small amount of airflow helps to evaporate this moisture and keep it moving out of the system. Under these conditions you baselayer dries more quickly. With a dry baselayer you are warmer and feel more comfortable.
Soft shells also avoid the problems of condensation and icing that plague waterproof/breathable fabrics. Waterproof/breathable membranes seal off air flow so effectively that the dew point inside your clothing system shifts all the way to the outer shell. It’s warm inside your layers but the temperature abruptly drops at the thin fabric of your shell jacket. This sharp temperature shift causes moisture to condense on the inside of the shell fabric. Anyone who has experienced frosting up on the inside of a breathable shell knows what this is like. All that frost is moisture waiting to soak your insulating layers.
Since soft shells lack a semi-permeable membrane they don’t develop a sharp temperature gradient at the outer layer of the system. Instead, temperature tends to vary gradually from baselayer to shell. Moisture passes through the system and doesn’t condense on the outer shell. This keeps the wearer drier and more comfortable.
What about Wind Shells?
The main difference between soft shells and wind shells is durability. Soft shell fabrics are heavier that the ultralight fabrics used in wind shells. This means they hold up better for rock climbing, tele skiing and bushwhacking cross country on a backcountry hunt. If you are a three-season backpacker or canoeist you can likely get by without this heavier shell layer. If you enjoy winter adventures you’ll appreciate the added toughness, warmth and stretch that soft shells offer.
Soft Shell or Not
If you start looking for soft shell garments at your local outdoor store you’ll run across a lot of clothes that are called soft shells even though they incorporate some kind of semi-permeable windproof and water resistant membrane. The term “soft shell” has expanded to include everything that is isn’t a fully waterproof hard shell. In fact, one manufacturer I used to work for sold a range of clothing that were billed as waterproof soft shells. They were waterproof, and stretchy and had a fleece lining–a real category bender.
Current offerings from many brands include shells that feature windproof membranes like Windstopper or similar proprietary fabrics. As I suggested in the article on wind shells, and midweight jackets, these membranes are less than ideal. In cold weather any windproof membrane, regardless of how breathable it is, will create the same kind of condensation problems found in fully waterproof/breathable hard shells. For the most functional and versatile cold weather shell, avoid shells with membranes. Stick with air-permeable, stretch-woven fabrics.
Fabrics without stretch can fill the role of soft shells, they just don’t offer as much freedom of motion as their stretch-woven counterparts. Military issue soft shells don’t have as much lycra in their fabric as commercial soft shells, mostly to boost durability in the hands of soldiers. They still function perfectly well as tough, versatile outer layers.
Years ago I experimented with a fully breathable winter shell made from two layers of Versatech polyester microfiber. It was a knee-length anorak sewn from a pattern at the back of Garret and Alexandra Connover’s book: A Snow Walker’s Companion. The anorak blocked the wind, turned away snow and dried quickly. It was a big performance upgrade over waterproof/breathable shells. Wintergreen Northern Wear in Ely, MN manufactures a far more refined version of an arctic anorak that is popular with mushers and winter explorers. Arctic anoraks are fully breathable and air permeable, so they tick the boxes for a proper winter shell. However, their specialized design features make them a little less versatile for a full range of outdoor activities.
Like wind shells, soft shells come from the manufacturer with a durable water repellent treatment on the fabric. This DWR helps to repel light precipitation and prevents the outer shell from soaking through. My experience with DWRs is that they all wear out fairly quickly in the field. Once your shell has been soaked a few times, the DWR won’t be as effective as it was when brand new. DWR can be reactivated by tumble drying your clothes on low (be sure to check care instructions so that you don’t shrink your gear!) or with spray-on or wash-in treatments. I’ve more or less given up on this sort of thing. To me it seems like chasing your tail. Stretch woven fabrics work just fine once the DWR has aged a bit and it isn’t worth my time an effort to constantly try to renew them. I almost always use these fabrics in snowy and cold conditions rather than rainy weather, so the DWR isn’t as critical. That said, if you are concerned about keeping the DWR on your jacket fresh there are plenty of products available to help.
Soft shells offer more features than wind shells. They are intended to be tougher and more functional than the minimalist shells suggested in Layer 4 of this system. Fabrics are heavier for durability and typically feature a bit of lycra for stretch and freedom of movement.
Soft shell jackets will have chest pockets, velcro adjustments at the wrist, drawcord hems and a hood. they may have additional pockets on the chest or sleeve. Jackets should be longer than wind shells–hip length is right. I’m a big fan of hoods on soft shell jackets. Tucking your head into a hood makes a big difference if you’re starting to feel chilled, and a hood keeps snow from dropping off trees and down your collar.
Soft shell pants come in a range of features, often with reinforced cuffs, side zips and ankle zips. Ankle zips on bottoms make it easier to get them on and off over bulky winter footwear and zippers on the upper leg can help with ventilation if you start to overheat. Cargo pockets or flat thigh pockets are helpful spots to tuck a map and compass, bandana or pair of liner gloves. Reinforced cuffs reduce wear from skis, boots or snowshoes.
Stretch woven fabrics come in a range of weights. Heavier woven fabrics are warmer and more wind resistant. Lighter fabrics dry more quickly and are lighter in your pack. Something middle of the road will get the job done. Steer clear of ultralight fabrics that aimed at trail running, these won’t be durable enough for many winter activities and don’t offer the features you’ll want in a winter shell. Also avoid the heaviest fabrics that feature an inner fleece layer. You’re looking for a versatile shell that you can use in conjunction with your other insulating layers and a fleece-lined soft shell will be too specialized. Keep it simple.
Color in soft shells isn’t as critical as it is in wind shells. We won’t be using these shells as sun or bug protection in hot weather, so it isn’t as important to choose a light color that won’t bake you in the bright sun. In fact, in cold weather it can be nice to have your shell soak up a little extra heat if the sun pokes out through the clouds. Choose whatever color makes you happy. Bright colors look good in photos. Drab colors or camo blend in for nature watching or hunting.
Your soft shell layers should be sized to fit comfortably over all the other layers in the system up until now. This means for the top you’ll need to be able to layer over baselayer, lightweight fleece, midweight jacket and windbreaker. For bottoms you’ll need to fit over baselayer and lightweight fleece. For some people this will mean going up a size from what you normally wear. Some companies size their soft shells with layering in mind. Others size them for a trim, athletic fit. It’s important to make sure that whatever you choose will fit over all your other layers without limiting your comfort or range of motion.
Buy This, Not This
You’re looking for a hip-length, hooded jacket in a stretch woven fabric. Pants should be a similar fabric and feature ankle zips for easy on-off. At time of writing good options are available from Outdoor Research, Patagonia and Arcteryx among others. Pick your favorite color.
If you’re looking for an affordable option and don’t mind camo, search the surplus stores for an ECWCS Level 5 jacket and pants. They cost about half as much as commercial soft shell optons. Make sure you look for the non-fire resistant versions. These are lighter and more breathable than the fireproof alternatives.
Don’t by a soft shell with a windproof membrane. Don’t buy a soft shell with an ultralight fabric. Don’t buy a soft shell with a fleece lining.
The PCU Protective Clothing Uniform: A Buyer’s Guide and Clothing System History
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15 thoughts on “A Simple Outdoor Clothing System Layer 5: Soft Shells for Cold Weather”
Thanks for an interesting take on softshell for winter. About 2 decades ago I replaced my ice climbing waterproof/breathable shell with a Patagonia Krushell; that and the next-gen Ready Mix are my go-to shells for cold and snow. These are microfiber-based rather than stretch-woven, but the principle is the same: improved breathability, full features, surprisingly sturdy. Also, lighter than stretch-woven, though not as breathable. But your point is well made – no Gore-Tex, eVent, NeoShell will work as well in the cold as will a softshell…
It appears that Patagonia has given up on stretch-woven for upper body. Where would you look for a stretch-woven jacket today? Arc’teryx still make one it appears (Gamma LT?). Black Diamond has a couple. I have one of the Alpine Start hoodies; minimal features, heavy for a windshirt but light for a stretch-woven jacket, and made from a surprisingly tough Schoeller fabric. I tried an OR Ferrosi jacket, but seemed to lack wind resistance and got beat up quickly. Any other players I should be aware of?
I love some Patagonia clothes but sometimes I think they’re innovative to a fault. Maybe it’s true innovation. Maybe its a new designer trying to make a mark. Who knows? They’ve ditched a lot of products that I think are absolutely key including stretch woven jackets and silkweight bottoms.
Other than Arcteryx, BD and OR I’m not sure where to look. Likely some European brands as softshell always had a firmer foundation over there. RAB might have something. And of course there’s always eBay. That’s where I picked up my used Hooded Guide Lite jacket. I got a good deal a few years ago. These days prices on used Patagonia are through the roof.
The BD Alpine Start hoody is my wind shell of choice. I don’t mind the extra few ounces given its durability and breathability. I’m thinking of getting the Gamma LT for the softshell layer. I’ve heard that the BD Dawn Patrol is also quite good. Other than these, I’ve seen some offerings from Beyond Clothing, Rab and Kuhl.
I read in a forum about the formation of frost on the inside of Gore-Tex shells when being active in very cold conditions. Thanks for the explanation about the dew point. It all makes sense to me now.
I was wondering whether this would still be an issue with the newer air-permeable membranes. They allow some passage of air, so this would let them breath a little like a soft shell. Some examples are – Polartec Neoshell, The North Face Futurelight and Outdoor Research Ascentshell.
I don’t have personal experience with any of these membranes so I have to make an educated guess. I suspect that these membranes will also frost up in cold weather because they are not truly air permeable. Anything that is fully windproof will push the dew point of the layering system to the outer shell.
Some years ago I used a Rab NeoShell jacket on a hike of Scotland’s West Highland Way. Despite having no pit zips the jacket breathed well for a waterproof/breathable materialI thought, and it got used a LOT because Scotland. I also have a Patagonia Knifeblade jacket, made from Polartec Powershield Pro (sort of a predecessor to NeoShell. This also breathes better than any Gore-Tex jacket I’ve used. I’ll wear it for ice climbing if conditions are warmer and drippy. But for winter I think it’s still not breathable enough to avoid condensation in the cold, or frost if it’s cold enough. True softshell materials have much more breathability, avoiding the trapped moisture.
Thanks for sharing your experience with these fabrics, Dennis. I suspected they would perform like this. My experience with Activent/Windstopper was similar. That stuff is really breathable but I sweat it up and frost it up badly in winter conditions.
Thanks for your thoughts on this Brian and Dennis. I was trying to see if a WPB air-permeable shell could replace both a hardshell and a softshell in this layering system.
Would be nice if we could do that but in practice it doesn’t really work. We were all convinced back in the 90’s that we could use Gore-Tex for this, but it seems like anything with any kind of membrane will sweat up/frost up, even the really thin membranes with crazy high rates of evaporative transmission. I suspect that air permeability is the critical element. Truly windproof layers all seem to suffer from the condensation/frosting problem.
First, thanks so much for this great series. IMO the best I’ve found on the topic of layering, and the competition is fierce 🙂
This is layer i’m struggling the most with, in particular I’m wondering what the value is of layering a softshell over an active insulation layer in a cold situation, since it seems to me that the latter already provides decent wind / snow protection.
Would a more direct route to additional warmth not be to layer some more insulation under the active insulation jacket?
Thanks for the kind words. Glad you’re enjoying the series.
How you run the system is definitely going to depend on circumstances. You might find yourself wearing active insulation over a grid fleece top without the soft shell. Or with a wind shell layered in between. Just comes down to what works and what’s easiest to adjust for different activity levels and temperatures.
In practice I rarely use L3 when on the move. Whether active insulation or fleece. It’s more of a semi-sedentary layer. If I’m active I’m typically good with baselayer, grid and some combination of windbreaker and soft shell.
I think the question you’re asking is, “if we have active insulation, why do we need a soft shell at all?”
Here are a few reasons:
1. Durability. The shell fabrics on active insulation pieces are very fragile. They’re thin to allow for breathability and air permeability. If you know someone who’s used a Nano Air or similar jacket hard in the field you know that they get absolutely shredded. Running a soft shell over the top helps protect these expensive and delicate garments from wear.
2. Wind Resistance. Adding a soft shell over L3 active insulation reduces the air permeability of the insulation layer, making it warmer. It’s another dial you can twist to fine tune the system when its cold and the wind is really howling.
3. Fit. If you size your active shell to fit more than a grid fleece under it it will be too large to wear within the rest of the clothing system. You would have to size up your soft shell and high loft layers to make it work, and that would limit their versatility when used with the rest of the system.
4. Fit. Soft shells are typically longer than active insulation jackets which gives them more overlap with bottoms and better protection from wind and blowing snow.
5. Versatility. If you’re wearing baselayer or grid fleece and the wind picks up you can throw on a soft shell to reduce evaporative cooling. You don’t necessarily need the L3 insulation layer, you just need to cut the wind. To accomplish the same thing with active insulation you’ll probably need to shed the grid. Sometimes you just need to cut the wind, not increase insulation.
I see active insulation as an upgrade to fleece in the mid-layer. Not an effective outer layer. It lacks the versatility and durability that you need in a shell.
There are lots of different ways to put together a layering system, and outdoor clothing companies are constantly developing new products to drive sales. The idea behind the Simple Clothing System is to come up with something that’s as universally effective and versatile as possible. Skipping the soft shell reduces the effectiveness and versatility of the system for winter travel.
Yep, that is exactly what I was asking. Thanks so much for this comprehensive answer.
You bet! Thanks for participating in the conversation.
One more thought, Ben. If I were looking to add more warmth to the system without adding a lot of bulk I would consider adding a tech fleece or active insulation vest sized to fit within the full system.
I’ve looked at these for a while and considered adding one to my closet. Just haven’t pulled the trigger. I’ve also rarely encountered winter conditions that require more insulation than the current system provides. As noted in this post, I was severely overheated skiing at 25 below wearing the L3 jacket inside the system, particularly my arms.
Based on this experience I might consider dropping the L3 jacket and replacing it with a vest.
That said, sticking to the original idea of a single system for all conditions, the jacket probably makes the most sense.
The rabbit hole keeps getting deeper :-). The winter experiments was a super interesting read, in any case.
To give you a bit of context, I am replacing the kit I’ve been using for the last 15 years, which consists of a fleece + hardshell, which in hindsight had much more room for improvement than I realised … Primary use case is 4 season hiking in Bavaria, so 15F is as low as it typically gets, so nothing like the -25F (!) you mention in your article.
Since our last exchange I’ve ordered a grid fleece from Rab and the Borealis soft shell. The latter departs a bit from your recommendation to avoid light soft shells, but i’m hoping that between that and the insulation layer it will cut enough wind for winter use (as mentioned, I’m not exactly in arctic conditions) while being really versatile for the other seasons or applications (eg jogging). Since my activities are not particularly abusive, it should check the durability box nicely.