Adding warmth – more clothes vs bag liner

I tried one of those liners you mention and they are not good at all, clothing would be better once its not constricting the down.

I do use a silk liner in summer to keep my bag clean.

Liner is a bit unwieldy and single-use. Extra clothing is probably preferred as long as it's dry (i.e., not the stuff you hiked in) and doesn't compress your bag's insulation.

fwiw, my friend really likes her silk liner, and says it makes a difference in warmth for her.

I know what you mean about clothes and bulk. My inclination would be to bring the 20 degree bag more often, instead of the 40 degree one.

Though that only answers half of your question!

If you toss n' turn, a liner will tangle you up like a mummy! I hate 'em for this reason, although they do keep the bag clean as Stephen mentioned.

They, since thinner, added less warmth for me then my thin base layer. If you get one, go with the silk as mentioned above for "slipperiness".

Bring the warmer bag or add a puffy jacket & pants (I use Montbell's UL inner pants & Parka).

A silk liner lasted all of 5 minutes from time of purchase to being sent back. I have never been a fan since. Mimicking twisting/turning as I usually do throughout the night, the thing constricted until I got frustrated and kicked it off. That being said, a VPB liner is absolutely essential in multi-day winter outings with a down bag, unless you have opportunities to dry it out.

For the rest of the year and the rest of our adventures it's always going to be recommended wear additional layers to compliment the warmth of an underachieving bag. The demigod, Ueli Steck, climbs 8k peaks in a 20/32F bag wearing his puffy pants and puffy jacket. For mere mortals like myself, putting a down sweater on backwards and leaving the 'back' unzipped adds 10, maybe 15F warmth. It also provides convenient pockets for warmed nalgenes :)

+1 to Mitch's "backwards" jacket method.

Down clothes are the most weight efficient way to add warmth, but yeah sleeping in a puffay isn't that comfortable.

I find a base layer warmer than a liner. It creates a cozy micro climate. I wear 100 wt fleece long johns and a 200 wt fleece jacket when it's cold. They do double duty as sitting around in camp clothes. I don't put them on until after all the camp chores are done. This way they don't get sweaty.

Ps: I also get all tangled up in a liner.

If you sleep in a tent you can also add warmth by covering up the mosquito net portions of the tent with solid fabric.

I've run into the same problem.

I'm a tosser and turner in my sleep, and always wake up tangled up in my silk liner.

I've been thinking of buying a pattern for a hooded sweat jacket and sweat pants, and sewing my silk liner into a wearable combo.

I think it would stop most of the tangling problems I've been having, and would still keep me a little warmer / keep the bag cleaner.

It would keep me warmer for middle of the night bathroom breaks too.

It might add an ounce or so to the weight though, but probably less so than more clothing would.

I do toss/turn quite a bit so a liner seems like a poor choice – I think I'll just stick to extra clothes and as mentioned take the 20 degree bag more often if I'm pushing the envelope for the 40 degree bag. I slept in the 40 bag one night when it went down to 38 or so and I had a mid weight base bottoms, mid weight top and put on my monkey man style fleece jacket and was cold – mostly my lower half… didn't enjoy that evening so if it looks dicey the 20 degree bag weighs actually not much more than the 40 (it's 800 v 600 fill down and lighter shell materials) – it's just bulkier.

An extra 2 oz of down in a quilt or bag, does more than any jacket or clothing. No better way than to take the right gear from the start.

Bag liners are mostly gimmicks unless your aim is to keep your bag cleaner inside.

1. Bag liners add almost no warmth unless well insulated.

2. Adding clothes for sleeping warmth supports the "dual use" mantra of lightweight backpacking.

3. It helps a lot if your bag, like my WM Megalite, is a bit large in the shoulder area so your added clothes don't compress the bag's insulation.