I have to second Pika's experience with a liner. I tried one once (trying to extend a 32*F bag and keep it clean), I got so tangled up in the thing that it took me several minutes to get out of bed. After a couple nights of that nonsense, I got rid of it.

I usually don't have to wear my baselayers when hiking, so they stay relatively clean, and that's what I wear to bed.

Most people try to extend their sleeping bag's warmth by wearing all their insulating clothing inside (which will also take up more of the space inside. I have to do this when the temp gets down to the low 20s F. Some deliberately try to extend a lighter sleeping bag by investing in puffy (down or synthetic) pants as well as a puffy jacket with hood to use for sleeping. I personally don't approve--I want an extra allowance for really cold nights (like the time it got down to 15* in the Cascades in September). Remember that a warm cap, warm socks and a well-insulated sleeping pad are needed to keep you warm. The EU test for sleeping bag warmth for 20*F has the "dummy" wearing base layers, a knit cap and on a pad whose R value is 5.

A fleece liner will probably add at least 12 oz. to your bag. I have no idea of how much it helps the temperature rating.--you'll have to try it. Forget silk; there's no real warmth to it.

Are you sure you don't want to return the bag and exchange for a warmer one?


Edited by OregonMouse (03/12/15 01:21 PM)
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May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey