What is Layering? 

Layering is a critical skill that helps us stay comfortable and safe in the backcountry.  The backcountry is a dynamic environment that can change from ideal to inclement in a matter of hours. Our bodies undergo rapid changes as well, going from cold to hot and vice versa in a matter of minutes as we exert ourselves, slow down or stop moving. 

A layering system is the group of layers we bring with us each day that allow us to adjust to our environment and our level of heat generation.  Layering systems are composed of base layers, insulation layers, shells (jackets and pants) and puffy jackets (aka parkas) as well as socks and gloves.  We'll discuss the function of each of these layers and provide recommendations on our favorite pieces in each category and the features that make them shine.

Ski touring on a cold day on Mt Shasta.  Proper layering is critical in cold, stormy conditions!  Photo: Zeb Blais.

Functional layering systems help us moderate our temperature in a variety of situations. The goal is to prevent ourselves from being too cold or too hot.  If we can prevent shivering or sweating, we'll be more comfortable, perform better and be safer in a hostile winter environment.

Choose your layering system based on the activity you're going to do and the environment you'll be doing it in.  Backcountry skiing is a cardio-based activity, with moderate to high output on the ascent, short to medium breaks for transitions and low cardio output during the descents. The environment is generally cold in the winter and can range from sunny and calm to blizzard conditions. Our layering system needs to be capable of managing these scenarios, through adding and subtracting layers throughout the day, to keep us warm and dry.

Warm, breathable layers like synthetic puffy jackets, pictured here, are perfect for aerobic movement in arctic temperatures, like the ones we experienced on this unseasonably cold tour in January 2024 on Mt Baker. 

Layering Systems for Backcountry Skiing and Riding

The following layering system works well for most backcountry skiing & splitboarding adventures.  We can easily add layers if we're going to a colder zone like interior British Columbia or remove layers if we're doing a late spring tour in Tahoe, but this system is a good starting point:

⬇️  Backcountry Skiing & Splitboarding Layering System

The Layers

Lets Dive into the Layers of a Backcountry Skiing Layering System

• Base Layers
• Insulation Layers
• Shell Jackets and Pants
• Puffy Jackets (Parkas)
• Socks
• Gloves and Mittens

We'll finish up with a discussion on How to Layer in the Field.

Base Layers

Base layers help regulate our body temperature by keeping us dry.  They do this by wicking sweat away from the body into the air or into insulation layers.  Wicking is a complex process and the range of performance between different materials is huge.  If your base layers don't perform, your layering system won't perform well either, so these layers are critical to our layering system. 

You've maybe heard the old adage "Cotton Kills."  This stems from cotton's inability to wick water away from the skin.  Instead, cotton absorbs water and holds it close to your body where it increases heat loss through conduction.  This mechanism of heat loss increases the potential for hypothermia.

Synthetic materials, and to some extent wool blends, pull sweat away from your body and draw it to the surface of the garment (wicking), keeping your skin drier, and preventing heat from being conducted away from your body. Inevitably, all layers get soaked through when we're working hard in the mountains, but synthetics and wool blends will dry much quicker as the wicking action pulls moisture from the body to the air (or into the next layer in our layering system).

A Rab Synchrino Wool Blend Base Layer(left) and a synthetic sun hoody base layer, the Rab Sonic (right).

Wool vs Synthetic Base Layers

The biggest benefit of wool is its natural odor fighting qualities.  Wool is typically more expensive and not as durable as a similar garment made of synthetic material.  Despite these drawbacks, wool advocates turn to the material for its natural bacteria resistance (and therefore smell resistance) and comfort.  It makes a big difference, especially if you're on a multi-day backcountry trip!

Synthetics are durable, less expensive and have excellent wicking properties.  The major drawback to polyester and nylon is that they quickly build up bacteria that cause body odor. Synthetics have a way of building up bacteria and retaining smell that is difficult to get rid of and often reappears shortly after washing!

Base layers come in a variety of weights for the upper body and lower body. Weights range from thin "silk weight" layers to heavy "expedition weight" fleece. When choosing a base layer weight, it's important to think of what climate you're backcountry skiing and riding in and what layers you'll be pairing it with.  For me, the decision to wear long johns (base layer pants) or not and what weight to choose is a major one for my layering system.  Once long johns go on for the day, they don't come off until you're back at the car!  For the West Coast ranges like the Sierra Nevada and Cascades, the temperatures are generally moderate, and you might not need more than a silk weight legging under your hardshell or softshell pants. You may opt to go without base layer pants if you have comfortable soft-shell pants. In the Rockies, interior British Columbia, or on the East Coast your go-to base layer pant might be mid-weight and you might need to pull out the expedition weight from time to time.

Insulation Layers 

Insulation layers have become much more technical over the years and are critical pieces for inclement winter weather. Depending on the climate (cold, continental climate, warm coastal climate, high-altitude climates or others) and your objective (fast and light, slow and steady, extremely remote, etc) you will want to put some serious thought into which insulation layers to bring.  

A Rab Graviton Fleece Hoody (left) and a Rab Xenair Alpine Jacket (right).

Generally, you'll want to have layering for what you think you'll need for the day PLUS a puffy jacket for breaks and emergencies. In cold climates this means I'll usually take two midweight layers that complement each other plus puffy parka. Complimenting each other means that these layers have different features so that the layers can be used separately or paired together to keep you warm and comfortable in a huge range of conditions.

For example, my go-to midweight insulation layers for cold weather backcountry skiing are a mid-weight fleece and a breathable synthetic puffy.  If there is no wind and no precipitation, the fleece breathes well and helps my base-layer wick away moisture from my skin. In windier and colder conditions, where I don't need as much breathability, a breathable synthetic puffy jacket will provide more wind resistance and insulation.  There are lots of options for these layers, such as the Patagonia NanoAir (the revolutionary piece that put this category on the map).  The Rab Xenair has become my all-time favorite layer due to its warmth and comfort in a wide variety of conditions. In cold climates, I often find myself wearing it on the skin track and in warmer temps it serves as my puffy. In very cold conditions (e.g. Japan, Interior British Columbia, or the Cordillera Blanca in Peru), I often pair the fleece and light synthetic puffy to add insulation and manage the moisture pulled away from my body by my base layers to keep me dry.  

Shell Jackets and Pants

Hardshell 

Shell layers, often called Hard-Shells, are layers with the primary function of keeping water off of us.  While shell jackets look like simple fabric, they are actually laminates consisting of a "face fabric" that faces the elements, a membrane (Gore-Tex or other waterproof breathable membrane) and a knit backer that faces the wearer.

Gore-Tex and other "waterproof-breathable" fabrics are neither! Gore-Tex is an ultra-thin membrane of ePE (expanded polyethylene) material that is sandwiched with a layer of external nylon "face fabric" and a knit backing layer that faces the body. The membrane contains micropores that allow small molecules (water vapor) to pass through the membrane, while preventing larger molecules (liquid water) from passing through.  When we sweat, the vapor produced by our bodies is allowed to escape through the Gore-Tex membrane, keeping us drier and more comfortable. At the same time, when it's raining, the Gore-Tex membrane prevents the larger water molecules from passing through the jacket and drenching us. Additionally, Gore-Tex & others are also treated with a Durable Water Repellent (DWR) finish that causes water to bead up and shed off the jacket.

A heavy-duty Gore-Tex Shell, the Rab Khroma Diffuse Gore-Tex Jacket (left) weighs in at 624g/22oz (Size M).  The lighter and less featured Rab Namche Gore-Tex Paclite Jacket (right) weighs much less at 364g/12.8oz in size M.

Unfortunately, neither the breathable or waterproof features play out at 100% efficiency. In torrential downpours, it's nearly impossible to stay completely dry as there is always some imbalance between the waterproofness or breathability of the hardshell.  In other words, water will wither penetrate the membrane and get you wet from the outside, or it won't breathe effectively enough, and you'll get wet from your sweat not being able to escape the membrane.

Once the DWR finish can't keep up with the outside moisture, the nylon fabric becomes wetted and it's a matter of time before you'll start to get wet. From that point, the wearer gets wet from water working its way through the Gore-Tex membrane or if membrane continues to function then the user's sweat condenses inside the jacket creating the same problem. Similarly, the breathability of Gore-Tex style fabrics doesn't allow for a high enough release rate of water vapor through the membrane to keep up with sweating for most people, resulting in moisture build up and a clammy feeling inside the jacket.  

You might be thinking: So why would I ever want to use a Gore-Tex layer?  Gore-Tex is an incredibly valuable layer in the backcountry for certain people and certain conditions.  

I use Gore-Tex all the time when:

1. It's raining or snowing. Gore-Tex is generally the best option for any type of precipitation, especially when it's cold and you're not planning to sweat as much.
2. It's windy. Hard shell layers like Gore-Tex are excellent for blocking wind. A day with moderate wind can create severe wind chills and a Gore-Tex jacket and pants goes a long way toward preventing heat loss from convection.
3. It's Cold. Gore-Tex is another layer that helps us trap heat. Trapped air is the best insulator, so the air inside your jacket will always be slightly warmer than the outside air. Even though it is not renowned for its insulating properties, Gore-Tex layers help keep heat in by trapping warm air and preventing radiation and convection loss.

Softshells vs Hardshells

Softshell has a much looser definition than hardshell.  Softshell is a material that prioritizes breathability but also tries to provide moderate protection from wind and precipitation.  Some softshell fabrics use a membrane laminate while others rely on tightly knitted fabric and DWR to provide weather resistance.  There's a wide range of weights, performance and weather protection within the softshell category, so make sure you choose what works best for how much heat you generate and where you're planning on using these pieces.  Folks who experience rain and wet snow don't tend to own as many softshell pieces as their counterparts in colder or drier climates!

For most people, softshell pants are better than hardshells, offering better performance and lower cost. Gore-Tex is a great material for specific use cases, but in most environments, other than extreme cold and extreme wet, softshell pants will be more comfortable and help you perform better by reducing sweating. 

What is a softshell? Softshell is a loose term that refers to synthetic garments with no waterproof membrane or a membrane that highly prioritizes breathability over waterproofness. These garments have a Durable Water Repellent (DWR) finish that provides a modest level of weather protection for light precipitation and wind. The highly breathable nature of softshell material means that it's much better at keeping up with expelling the moisture you create when sweating.

The Rab Tour Softshell Pants offer great breathability and freedom of movement. 

Puffy Jackets

Puffies are essential. The idea behind puffy jackets is that they are designed to be incredibly warm while also being light and packable.  Puffies create their high warmth to weight ratio and packability using high loft insulation and very thin, lightweight face fabrics.    

The Rab Neutrino Pro is an 800 fill power belay parka that earns its keep in cold backcountry climates or climbing 4,000m peaks in the alps. 

If you've ever taken time for an extended break on a ski tour, you know the value of a good puffy jacket.  Puffy jackets help to prevent your body from cooling down rapidly when you need to stop for a long period of time.  Whether you're taking a break, digging a pit or managing a gear malfunction or an injury, a puffy can be a layer that keeps you comfortable or a lifesaving piece of emergency gear.

Puffies come in two varieties: Down and Synthetic. Down has proven to be a hard material to imitate and while synthetic insulations have come a long way in recent years, they still cannot compete with the loft of high quality down. We explore both types of insulation and discuss the pros and cons of each below.

Down Insulation

Down is the undisputed champion of warmth to weight ratio and packability. Sometimes you can't beat nature when it comes to engineering! The best down comes from European Geese and has the most loft per gram. Down is tested and given a fill power rating, which describes how many cubic inches volume the down has per ounce of down. The highest fill ratings that can be achieved are 1000 fill power, which is only available for the highest caliber down garments.  Generally, I shoot for 800 fill power for most performance layers I use for backcountry skiing and alpine climbing. 800 quality down provides great packability and warmth to weight ratio. 650 fill power is common for less technical pieces, but these pieces are bulkier and less performance oriented and it's often worth paying the extra money for higher warmth, lighter weight and better packability. 

Fill Power is not the only number to think about!  Just because a jacket says it's 800 fill power down doesn't mean that it will be warm! It also depends on HOW MUCH down is in the jacket. This is the fill weight of the garment, which is just given as ounces in the US.  For a mid to heavy weight parka jacket that one might use on cold days in British Columbia or transitioning on a skin track in Hokkaido, Japan the fill weight would be around 12 ounces. 

To recap, the warmth of a down garment is based on the quality (fill power) and quantity (fill weight) of the piece. A very light garment with high fill power doesn't mean it will provide the warmth you're after for your day in the backcountry and neither does a low fill power jacket with a lot of down. So make sure you look at both fill powder AND fill weight!

One problem with down (surprisingly enough since it comes from waterfowl) is that it is not waterproof. When down gets wet, it clumps together and loses its loft, and therefore its insulating properties. This can make down a pretty big liability in wet environments, especially ones that quickly change from warm and wet to cold and wet. To solve this problem, companies created a process to waterproof down by coating the tufts of feathers with a chemical called PFTE. This prevents clumping and allows the down to retain some of its loft.

Synthetic Insulation

Synthetic Insulation is humankind's attempt to imitate down. Despite not being able to compete with high quality down in terms of warmth to weight ratio or packability, synthetic insulation maintains its loft even when wet, allowing it to function better in wet and continuously damp environments. While it's a personal choice, I prefer the feel and performance of light to mid weight synthetic insulation pieces like the Patagonia NanoAir/Rab Xenair to their down counterparts like the Patagonia AlpLight/Rab MicroLight Down as they seem to move moisture better and provide improved comfort in a wider range of conditions.

The Patagonia Nano Air (the piece that revolutionized insulation and created an entire category of insulation layers) is a synthetic insulated puffy jacket.  It functions as a parka in warmer environments like California and Washington, or as a mid-layer on colder tours.

Socks

Socks should be wool or synthetic. You might even consider footbed heaters if you live in colder areas.  In general, I stick with lightweight socks regardless of temperatures since my boots are snug.  Adding a thicker sock can reduce circulation and makes your feet colder!  In very cold temperatures heated socks or heated footbeds can provide a heat boost to keep your toes comfortable all day.

High quality synthetic and wool blend socks make a massive difference during long days in the backcountry - don't skimp on socks!

Gloves & Mittens

Gloves are a critical part of our layering system for backcountry skiing. Gloves protect our hands from cold and wind, abrasive snow surfaces and from being pinched in bindings or boot buckles. For run of the mill ski tours, I carry two pairs of gloves - a lightweight, dexterous pair with little to no insulation like the Mammut Astro or Rab Khroma Tour, and a mid-weight, insulated pair like the Rab Guide GTX 2. It's important to note that these gloves are independent of one-another and that the midweight glove is not just a shell that slides over the lightweight glove. This provides redundancy in the event that you lose one glove, or even worse, two!

The light pair of gloves allows hands to shed heat while skinning uphill and provides dexterity for operating your gear. I rarely skin without gloves and with two independent gloves systems I don't have to worry about getting my gloves damp with sweat or snow. I look for gloves that allow me to operate zippers, bindings, remove skins, assemble splitboards, operate my transceiver, shovel and probe. I consider my lightweight gloves to be part of my avalanche rescue system - trying to perform an avalanche rescue without gloves is a recipe for disaster.

Midweight gloves are kept dry in my pack and are reserved for descents and skinning in extreme cold. If it really is that cold, I usually add a mitten or a heavyweight glove like the Rab Khroma Pro GTX to my kit to make sure I can always keep my hands warm. If you know you're in for a cold day, a good trick is to activate a set of chemical hand warmers and drop them into your big gloves at the beginning of the day. By the time you need them, the warmers will have pre-warmed your mitts and you'll instantly boost your hand heat!  Mittens are a good option if your fingers run cold, but they are also much less functional for dealing with gear, especially in rescue situations.

The Mammut Astro lightweight glove and the Rab Guide 2 GTX Midweight Glove makes a great glove system for mild, snowy climates like the Sierra Nevada and North Cascades ranges. 

How to layer in the field

We've covered a lot about layer technology, but which layers should we bring and wear? Each day I go backcountry skiing, I check the weather and tweak my layering system. Here are a few tips to get your layering system for backcountry skiing and splitboarding dialed:

1. Plan your layers for where you're headed, not where you are. It can be difficult to anticipate what layers you'll need when the weather outside your house is beautiful (or much worse) than the weather where you're going backcountry skiing or splitboarding. Altitude, terrain features and microclimates have a big effect on the weather, so try to get an accurate forecast for the zone you're headed to (Bookmark our weather pages if you haven't already) and throw extra layers in your car - you might be glad you did at the trailhead!
2. Don't be silly, start chilly! You may have heard the adage "Be bold, start cold" or "Don't be silly, start chilly"! This just means that if you're perfectly warm and comfortable at the trailhead and don't strip a few layers before launching, you'll be sweating 10 minutes into the skin track! A good way to determine the layers you should be wearing is to think about what you'd choose to wear if you were going for a light jog in that weather. You should be cold to the point of shivering slightly when you start. Ten minutes in, you'll be warm and dry and won't have to stop to remove layers!
3. Don't Sweat.  Do what you can to avoid sweating, especially when getting wet could be dangerous. If you anticipate you'll continue to generate too much heat and sweat, take the time to pause and remove layers. You might also consider moving slower if you're concerned with sweating too much.  Sweating not only makes you wet in an environment where that can be dangerous, it also causes dehydration. The more you sweat, the more you'll have to drink to replenish the lost water, so doing what you can to limit sweating allows you to carry less water. Some folks just sweat more than others and it's difficult to prevent sweat even in extreme cold. If that's you, be aware of it, and take steps to try to minimize your sweating.
4. Plan your layer changes and layer for the terrain ahead. Often in backcountry skiing, we have spots we know we're going to stop for a transition, maintenance break or feel like the weather will change (treeline to alpine, gaining a ridge, entering a couloir, etc). Try to plan what layers you'll want for that section of skinning or riding. As you're approaching the transition point, think about the ideal layers you'd like to be wearing in that section of the ski or climb. Do you want to add bigger gloves for the steep booter because your hands will be in the snow? Should you drop your fleece layer to keep yourself cool as you generate more heat? Will you need a fleece or shell layer for the windy ridge coming up?

Layering for backcountry skiing and riding makes a huge difference for both comfort and safety.  Investing in high quality layers will make your trips more comfortable, more rewarding and more fun!  Experiment with layer choices based on where you ride and how you move and notice which layers you feel help keep you warm and dry!

What Questions Do You Have About Layering?

Let us know what questions you have about layering for backcountry skiing and splitboarding!  Email us at info@blackbirdguides.com - we'll get back to you and update our blog to help others learn to layer effectively for backcountry skiing!

About the Author

Zeb Blais is an IFMGA Mountain Guide and AIARE Avalanche Course Leader based in Truckee California. He loves all the disciplines of mountain guiding - ski, rock and alpine climbing - but skiing is his first love.  In the winter he enjoys backcountry skiing, guiding local and international ski trips, and teaching avalanche courses across the west coast, from Bishop, California to Mt Baker, Washington.