Today I’ll review my winter backpacking sleep system. Your daytime shelter system consists of your clothes. Your nighttime system is a bit more complicated. It is important to think of both as “shelter systems.” A system isn’t just one thing, it is several components working together. A winter backpacking sleep system is a layered set of defenses designed to protect you from the environment.

Layers in a Winter Backpacking Sleep System

We’ll start off by review the standard layering system. Everyone has heard “dress in layers.” Dressing in a lot of thin layers allows you to add and subtract clothing as needed to maintain the desired warmth. If you’re just wearing one thick layer and you get too hot, your only option is to take it off and be naked – but then you’re too cold. Thin layers work better.

But not every layer is the same. Each type of layer has a specific function. The layer(s) closest to your skin are your base layer. Their function is moisture management. They help transport moisture away from your skin, and they also add a little warmth. The next set of layers outward are your insulating layers. As the name implies, this layer provides most of your warmth. Your outer-most layer is your shell. It blocks wind and rain.

In some cases you may also add a vapor barrier layer between your base and insulating layers. The VBL prevents body moisture from saturating your insulation.

Base Layer for Winter Backpacking Sleep System

My sleeping base layer isn’t much different from my hiking base layer. In fact, if I’m on a one night trip, my sleeping base layer is simply the base layer I plan to wear on day 2. The most effective base layers are either merino wool or a thin synthetic wicking material. Synthetic base layers are lighter, cheaper, and more durable while wool base layers are less smelly and softer on your skin. Some people find synthetic layers to be softer.

My winter backpacking sleep system base layer consists of a pair (or two) of wool socks, a pair of Hot Chilli brand top and bottom synthetic tights, merino wool or fleece gloves, and wool or fleece hat. This system doesn’t vary that much from trip to trip.

It is very important to put on a fresh dry base layer before going to bed. Any moisture against your skin is going to make you feel cold. On a multi-night trip, I will have one full base layer for sleeping and another for hiking. I switch to the night set as soon as I’m done hiking for the day. My day set goes into my footbox of my sleeping bag or quilt to keep warm overnight. I’ll usually change back into the day set as soon I wake up in the morning to get it back up to body temperature while still wearing my insulating layers.

Insulating Layer for Winter Backpacking Sleep System

The next layer out is your insulating layer. Depending on the temperature, this may be the most complicated layer of your winter backpacking sleep system. Mine consists of several components, which may be mixed and matched.

On my Feet

The first components of my insulating layer are the clothes that I put on when I get to camp. As mentioned above, I always change into a dry base layer when I reach camp. I also change into a dry insulating layer. On my feet, I keep the liners from my Baffin Borealis boots. Sleeping with them helps to dry them and keep from freezing. I also have a pair of Western Mountaineering booties that I can wear out of the tent or sleep in for extra warmth.

Pants

I then switch out my daytime soft-shell pants for a pair of Enlightened Equipment Torid Apex Pants. These puffy pants provide high loft insulation. Loft refers to their thickness: the thicker a layer, the better it insulates. Apex is a synthetic fill material. While synthetic fills are heavier and less compressible than down (feathers) they stand up better to moisture and I think they make a better pant.

Torso

On my torso I pull on a hooded fleece and my Mountain Hardware Phantom Hooded Down Parka. This parka is filled with 800 fill down that provides a high loft to weight ratio. I only wear my down parka in camp and for short breaks on the trail. Down becomes a lot less effective when wet, so you want to be careful.

Quilt or Sleeping Bag

I use a quilt instead of a sleeping bag. A quilt is like a sleeping bag that only closes around the feet and the neck. The bottom side is open. The reasoning for this is that when you lie on high-loft insulation, you compress it and it becomes useless. I find a quilt to be a lot more comfortable and less restrictive to sleep under, but some people think they’re drafty. My go-to quilt for the winter is an Enlightened Equipment Enigma 0.

Sleeping Pad

As mentioned above, a sleeping bag or quilt can’t keep your bottom side warm against the ground because you would compress the loft out of it. You need a sleeping pad to trap a cushion of air underneath you. I have two components. Most of my ground insulation comes from my inflatable Therm-A-Rest NeoAir Xtherm. This space aged pad uses reflective baffles to provide tremendous insulation for its weight.

Relying solely on an inflatable pad can be risky. If it pops, it becomes useless. I always carry around a section of Therm-A-Rest Zlite. The Zlite is a close cell foam pad that provides fair insulation but is highly reliable. A foam pad also makes a nice seat in camp or on breaks. I usually carry 6 panels in the winter.

Your Shell Layer is your Tent

Your outermost layer, your shell, is responsible for protecting you from the wind or rain. In the case of sleeping, it is your tent, tarp, bivy, or lean-to. My favorite winter backpacking tent is the Black Diamond Firstlight. It is fairly light for a winter tent and sets up extremely easily. I can set it up in less than 2 minutes and crawl inside out of the weather.

Full Winter Backpacking Gear List

Review of my Full Sleep System:

• Base Layer
  • Merino Wool Socks
  • Merino Wool top and bottom
  • Wool or fleece Gloves
  • Wool or fleece hat
• Insulating Layer
  • Baffin Borealis Boot Liners
  • Enlightened Equipment Apex Pants
  • Hooded Grid Fleece
  • Mountain Hardware Hooded Phantom Down Parka
  • Therm-A-Rest NeoAir XTherm
  • Enlightened Equipment Enigma 0 Degree Quilt
• Pillow
  • Hyperlight Mountain Gear Large Pillow Stuff Sack
• Shell Layer
  • Black Diamond Fistfight Tent