Sleeping bag liners used to be all about hygiene and were usually made from cotton. These days, there’s a wide variety of fabrics and functions with keeping a sleeping bag clean just one of the reasons to consider rather than the key one. Of course, the cleaner your sleeping bag, the less frequently you’ll need to wash it with all the potential anxiety that can entail, especially is it’s filled with expensive down.
Any liner will add to the warmth of your bag as it will add to the insulation value of the trapped air heated by your body; they don’t weigh very much and take up little space in a rucksack. That sounds quite technical but it simply means warming up the bag filling whether it’s light fluffy down or polyester wadding.
Cotton liners are popular as they can be washed easily and are pretty cheap. Fleece is an obvious fabric to add warmth to your bag but it’s not the only way to extend the range of comfortable use. Silk comes with a higher price tag but offers a greater range of flexibility, packs down really small and is also easy to wash; it feels pretty good as well. Simple in style, liners may be rectangular, tapered or mummy shaped; zips are rarely found on them.
As all liners can be used on their own, it pays to think ahead about what you might be doing. On its own, a fleece liner might be fine as a summer bag or for use as bedding on a flying visit to family and friends. A silk liner makes a great sleeping bag for use when travelling in hot countries. As liners may have been or can be treated with insect repellents and anti-bacterial concoctions, their use on gap years, backpacking trips and camping in all seasons is proof of their versatility.