Sleeping bag liners are designed with a few different purposes in mind. Many are designed just to keep the interior of the sleeping bag clean, so that you don’t have to go cleaning the entire bag in the washing machine every time you go camping or backpacking. Others are designed for warmth, and if you know what to look for, it’s not too difficult to find the warmest sleeping bag liner. Really, it all comes down to picking the right material for your sleeping bag liner.
Warmest Sleeping Bag LinerWhat to look for when looking for the warmest sleeping bag liner.
- Thermolite – There are a couple of possible choices for a warm sleeping bag liner, but thermolite is the best. It adds a whole bunch of warmth with as little bulk and weight as possible. Something like fleece will also add a lot of warmth, but will take up a lot of room and weigh a lot too.
- Shape – This depends on what shape of sleeping bag you have, but it’s worth mentioning that a mummy shaped sleeping bag, and thus a mummy shaped sleeping bag liner, will be warmer than the rectangular variety. Put simply, there’s less room inside a mummy shaped sleeping bag to heat at night.
Best Warmest Sleeping Bag LinerSome of the best choices when it comes to the warmest sleeping bag liners.
- Sea to Summit Reactor Thermolite Sleeping Bag Liner - Thermolite is one of the better sleeping bag liner materials when it comes to adding a lot of warmth to a sleeping bag without carrying around a big, heavy sleeping bag liner. This particular liner will add about 15 degrees of warmth, is mummy shaped and weighs 9 ounces, or 255 grams, which is a very good warmth to weight ratio.
- Sea to Summit Toaster Microfleece Mummy Liner - The other obvious choice when it comes to sleeping bag liner materials that will keep you warm is fleece. This particular microfleece liner weighs 1 pound 4 ounces, or 560 grams, and there's no word on just how much warmth it adds, though it will definitely be in the double digits. So a good, if heavy option if you prefer a fleece sleeping bag liner.
- Sea to Summit Thermolite Reactor Extreme Mummy Liner - The Reactor Extreme is one of, if not the warmest sleeping bag liner on the market. It's the kind of thing you want if you're trying to use a summer sleeping bag in winter. It weighs 14 ounces, or 396 grams, and adds an impressive 25 degrees of warmth to a sleeping bag. It's mummy shaped, as the name suggests, and is about the warmest sleeping bag liner you're likely to find.