A few things to look for when selecting a new sleeping bag include temperature rating, insulation, shape, size and weight, construction and materials, and features.
Temperature rating is a key factor for the winter as you’ll want a sleeping bag with a temperature rating lower than the coldest temperature that you think you’ll be in. It is often listed by the EN 13537 standard, which is decided through four parameters: upper limit, comfort, lower limit, and extreme. Some manufacturers conduct their own tests and have their own standards for setting a temperature rating. The temperature rating should match your activity and type of camping you’ll be doing, such as backpacking through the woods, mountain climbing, and car camping.
Insulation, typically down or synthetic, is what keeps you warm at night. Both materials have pros and cons. Down insulation has a better warmth-to-weight ratio and packs lighter and smaller, but it is typically more expensive and loses its properties in wet weather. The synthetic insulation traps your body heat inside the sleeping bag; with winter options, they only let a very minimal amount of heat escape.
The preferred shape for cold weather is the mummy, which is tailored to the shape of your body to increase heating efficiency. It is narrower toward your feet and widens near your head, it but wraps around your head to keep even the top of your head warm while resting inside. The traditional rectangular and semi-rectangular shape is typically used for milder seasons.
Size and Weight
Sleeping bag design has come a long way. They’re often available in regular and long for taller users, and options are even available for both male and female users. The goal is to select a sleeping bag that is closest to your body type to ensure a comfortable experience. Additionally, you’ll want to consider the activities taking place; for hiking or mountaineering, smaller and lightweight sleeping bags are more ideal, while car camping allows for larger and bulkier sleeping bags.
Construction and Materials
The quality of your sleeping bag also depends on what it’s made of and how it’s made. Specific materials work better than others depending on the conditions you’re in. The exterior is typically constructed from ripstop nylon or polyester and often waterproof and treated with a durable water-repellant (DWR) finish. The inner lining material is often polyester or nylon taffeta, as both materials are soft, comfortable, and breathable. You’ll want to look at how the sleeping bag is constructed to ensure a warm and comfortable night’s sleep.
Features of the bag differentiate one from another. This may include the addition of a hood to cinch up tight around the face to trap body heat, keeping the face as protected as possible. A draft collar fits around the top opening, near the hood, and limits the amount of cold air that enters the sleeping bag. A draft tube prevents air from entering through the zipper and a good sleeping bag design will cover the zipper. Additional features may include pockets for storage, a sack or bag to store and compress the bag when not in use, and the allowance for extra pads such as pillow pads and full-body sleeping pads. Most of the bags tested came with both a compression sack and mesh sack—you’ll want to store in the mesh sack as to not lose its loft.
You may still want to test how you fit in each sleeping bag prior to purchasing. Here are a few winter sleeping bags we selected for cold nights.
Editor’s Note: A version of this article first appeared in the January/February 2020 print issue of Tread Magazine.