Sleeping bag designs and materials have changed radically the past few years, and bags are warmer, more breathable, and lighter than ever before. But selecting a featherlight sleeping bag is a balancing act, and you’ll want to make sure you choose a bag that’s designed for the conditions of where you plan to use it. When you’re ready to shave pounds and ounces from your pack weight, here are three things that will help you dial in on the perfect overnight cocoon.
Sleeping bag ratings are estimates for how cold the air temperature can drop before you’re a bag feels like it’s not offering enough insulation, and too many people buy a bag that’s too warm. Think about the conditions where you’ll be camping and choose accordingly. Bunk down during a 50-degree night in a 20-degree bag and you’ll drip sweat by midnight. Also, consider double zippers that enable you to zip open the foot box for a bit of fresh air to cool off.
Down-filled bags are typically warmer per weight than bags filled with synthetic insulation, and they breathe better. Despite its insulative qualities, some people don’t like down because it soaks up water and loses nearly all its thermal properties when wet. But modern advances in down production have fostered much better insulation choices. If weight, breathability, and compressibility are concerns, this is a great time to consider a down bag.
A mummy bag, by design, conforms closely to the shape of your body. That’s how this bag design can be warmer than traditional sleeping bag designs, without the bulk. But not all bodies are alike. For smaller bodies, look for a bag with small dimensions so you don’t have thermally inefficient wasted space inside.