Forum
Buying gear? Please use these links to help 14ers.com:

More info...

Other ways to help...

Sleeping Bag Liners?

Info on gear, conditioning, and preparation for hiking/climbing. Gear Classifieds
User avatar
Posts: 192
Joined: Mon Jul 10, 2006 4:51 pm
Location: Westminster, CO

Sleeping Bag Liners?

Postby rleclair » Tue Dec 11, 2007 11:58 pm

What are y'alls thoughts about sleeping bag liners that claim to add 9-12 degrees to the warmth factor of a bag. For example, I have a Kelty Stratus rated to 35 degrees and have seen the "Sea to Summit Reactor Thermolite Liner" mummy bag liners at REI for around $50. Are they worth it or just a hassle?
"Thousands of tired, nerve-shaken, over-civilized people are beginning to find out that going to the mountains is going home; that wilderness is a necessity; and that mountain parks and reservations are useful not only as fountains of timber and irrigating rivers, but as fountains of life..."
John Muir

Posts: 91
Joined: Tue Sep 26, 2006 9:28 pm
Location: Denver

Postby Tim McMarmot » Wed Dec 12, 2007 7:45 am

I use a silk liner by Design Salt. It keeps my bag cleaner and makes it more comfortable, but I doubt it adds the warmth they claim. I've never used the Sea to Summit stuff, so I can't say for sure there.

Moderator
User avatar
Posts: 1571
Joined: Thu Aug 04, 2005 10:46 pm
Location: Boulder, CO

Postby USAKeller » Wed Dec 12, 2007 8:02 am

I have the Sea to Summit Thermolite Reactor liner and use it with a 15 deg. down bag. I couldn't tell you if it truly adds 15 degrees to the bag, but it definitely did something to keep me warmer when we woke up in the cabin at Lake Como and it was 1 degree outside last March.

I don't really think that the liners are a hassle, especially if you're going to be doing some cold-weather camping. And like Tim said, they at least can be used to keep the inside of your bag clean.
All we are called to do is do the next right thing.

User avatar
Posts: 567
Joined: Thu Apr 20, 2006 1:03 pm
Location: Littleton, CO

Postby Spam » Wed Dec 12, 2007 9:09 am

They are great for keeping your bag clean and they trap air closer to your body so I think it does keep you warmer longer if that makes sense.
"Getting to the top is optional, getting down is mandatory." -- Ed Viesturs

Posts: 178
Joined: Mon Jul 31, 2006 8:21 pm
Location: Castle Rock, Co.

Postby Van McDaniel » Wed Dec 12, 2007 9:48 am

I have a bag liner that I picked up several years ago. It is nothing more than an airtight as in non-breathable nylon sack that I use for cold(not cool)weather camping. It did take a little getting used to, I will admit. It is reccomended that when one uses it that one would be wearing poly-pro or silk long underwear and possibly some light weight gloves. If one were not wearing these items than the camper will get pretty clammy inside the sack after a few hours because the sack does not breathe as a gore-tex bivy would. After getting in the sack and then getting inside the bag with the aforementioned items on I did experience a bit of moisture build up that only lasted a few minutes....I suppose that a body at rest will only exude so much moisture and reach a maximum and then stop. The rest of the night was just another night in a sleeping bag. BTW, the sleeping bag was/is a -20 Below REI Alaskan goose down bag. When I got out of the bag early the next morning the outside temp was -11F below 0. The moisture that had built up on me and on the inside of the bag liner began to quickly evaporate and within a few minutes I was brushing away some very light patches of ice crystals and then everything was fine and normal. To my somewhat surprise, this thing seems to work. Although I did experience a little bit of a clammy feeling, it quickly went away after I got out of the bag....That is the downside. The upside is that my down bag was completly dry or at least I had not dampened it with any of my body moisture. That was over 20 years ago and I will still use the same bag liner on a COLD night with the same results. BTW, it would be a mistake to get inside this bag liner and then inside a sleeping bag after I had just done a lot of work or just after a hike or a snowshoe. You gotta do the cool down thing first.

How about on Denali? I have never been there but plenty of people on this site have been there and other high, cold places.
Eat Dessert First!

User avatar
Posts: 1975
Joined: Tue Jun 26, 2007 9:04 am
Location: Denver

Postby Presto » Wed Dec 12, 2007 9:55 am

We've got fleece bag liners and have used them camping in the winter and on glaciers. They work excellent and definitely keep us warmer. In the spring, when we go to Moab, we use the liners alone as our "sleeping bags".
As if none of us have ever come back with a cool, quasi-epic story instead of being victim to tragic rockfall, a fatal stumble, a heart attack, an embolism, a lightning strike, a bear attack, collapsing cornice, some psycho with an axe, a falling tree, carbon monoxide, even falling asleep at the wheel getting to a mountain. If you can't accept the fact that sometimes "s**t happens", then you live with the illusion that your epic genius and profound wilderness intelligence has put you in total and complete control of yourself, your partners, and the mountain. How mystified you'll be when "s**t happens" to you! - FM

User avatar
Posts: 428
Joined: Wed Feb 08, 2006 10:58 am
Location: Solon, IA

Postby JB Allen » Wed Dec 12, 2007 10:06 am

We use fleece and love them...
JB Allen...

User avatar
Posts: 281
Joined: Tue Dec 12, 2006 8:20 am
Location: Colorado

Postby strat1080 » Wed Dec 12, 2007 7:46 pm

I'm of the mindset to just wear more layers while sleeping. It is a good idea to have extra clothing in your pack. Extra clothing + a sleeping bag liner is over-redundant and just extra weight IMO.
Last edited by strat1080 on Wed Dec 12, 2007 7:49 pm, edited 1 time in total.
Quit whining and move your %$# up that mountain.

User avatar
Posts: 281
Joined: Tue Dec 12, 2006 8:20 am
Location: Colorado

Postby strat1080 » Wed Dec 12, 2007 7:48 pm

That sounds more like a Vapor Barrier than a sleeping bag liner intended to add warmth. It will add warmth as well but is more intended for expedition use to reduce the amount of water absorbed by sleeping bags through condensation. This can be very scary in very cold conditions.

Van McDaniel wrote:I have a bag liner that I picked up several years ago. It is nothing more than an airtight as in non-breathable nylon sack that I use for cold(not cool)weather camping. It did take a little getting used to, I will admit. It is reccomended that when one uses it that one would be wearing poly-pro or silk long underwear and possibly some light weight gloves. If one were not wearing these items than the camper will get pretty clammy inside the sack after a few hours because the sack does not breathe as a gore-tex bivy would. After getting in the sack and then getting inside the bag with the aforementioned items on I did experience a bit of moisture build up that only lasted a few minutes....I suppose that a body at rest will only exude so much moisture and reach a maximum and then stop. The rest of the night was just another night in a sleeping bag. BTW, the sleeping bag was/is a -20 Below REI Alaskan goose down bag. When I got out of the bag early the next morning the outside temp was -11F below 0. The moisture that had built up on me and on the inside of the bag liner began to quickly evaporate and within a few minutes I was brushing away some very light patches of ice crystals and then everything was fine and normal. To my somewhat surprise, this thing seems to work. Although I did experience a little bit of a clammy feeling, it quickly went away after I got out of the bag....That is the downside. The upside is that my down bag was completly dry or at least I had not dampened it with any of my body moisture. That was over 20 years ago and I will still use the same bag liner on a COLD night with the same results. BTW, it would be a mistake to get inside this bag liner and then inside a sleeping bag after I had just done a lot of work or just after a hike or a snowshoe. You gotta do the cool down thing first.

How about on Denali? I have never been there but plenty of people on this site have been there and other high, cold places.
Quit whining and move your %$# up that mountain.

User avatar
Posts: 2053
Joined: Thu Jul 14, 2005 8:30 pm
Location: Bellingham, Washington

Postby Aubrey » Wed Dec 12, 2007 10:20 pm

Jared Workman wrote:
USAKeller wrote:I have the Sea to Summit Thermolite Reactor liner and use it with a 15 deg. down bag. I couldn't tell you if it truly adds 15 degrees to the bag, but it definitely did something to keep me warmer when we woke up in the cabin at Lake Como and it was 1 degree outside last March.

I don't really think that the liners are a hassle, especially if you're going to be doing some cold-weather camping. And like Tim said, they at least can be used to keep the inside of your bag clean.


Ditto on the product and the sentiment.


I'll vouch, too. We also use the Thermolite Reactor. It's lightweight, small (a little bigger than a beer can), effective (although, I probably wouldn't give it 15 degrees; maybe 10), soft, and wicking (synthetics).

http://www.rei.com/product/705534

User avatar
Posts: 2053
Joined: Thu Jul 14, 2005 8:30 pm
Location: Bellingham, Washington

Postby Aubrey » Wed Dec 12, 2007 10:36 pm

strat1080 wrote:I'm of the mindset to just wear more layers while sleeping.


Not saying this method doesn't work; personally, I agree with it and I do it. But on one occasion, my feet were freezing in my sleeping bag so I put on two layers of socks (seemed intuitive). But I never got 'em warm all night long. After talking with a climbing partner the following morning, I went with his suggestion the next night: liner socks + sleeping bag liner + sleeping bag. My feet were warm that night.

Maybe it has something to do with trapped air / layers, and how "spacey" those layers are (i.e., if your "liner" is pressed against your body, like a sock, it's not going to trap warm air as much or as well?). I don't know. But based on this experience, I give liners props.

User avatar
Posts: 281
Joined: Tue Dec 12, 2006 8:20 am
Location: Colorado

Postby strat1080 » Wed Dec 12, 2007 10:58 pm

I've heard of some people using something called an elephant sock. Basically a garment large enough to fit both of your feet in. I guess my problem with something like a sleeping bag liner is that it is single-use and redundant. I imagine a a garment large enough to cover both feet could be made quite easily and weigh about as much as a poly t-shirt. At summitpost some people have reported being comfortable 30-40 degrees below their sleeping bag's rating wearing their insulating layers. I would think that the heat generated inside the sleeping bag would keep the temperature inside the bag at a nearly universal temp. Maybe your sleeping bag has cold spots near your feet. I've never had a problem with this. Your avatar is freaky looking by the way.

Aubrey wrote:
strat1080 wrote:I'm of the mindset to just wear more layers while sleeping.


Not saying this method doesn't work; personally, I agree with it and I do it. But on one occasion, my feet were freezing in my sleeping bag so I put on two layers of socks (seemed intuitive). But I never got 'em warm all night long. After talking with a climbing partner the following morning, I went with his suggestion the next night: liner socks + sleeping bag liner + sleeping bag. My feet were warm that night.

Maybe it has something to do with trapped air / layers, and how "spacey" those layers are (i.e., if your "liner" is pressed against your body, like a sock, it's not going to trap warm air as much or as well?). I don't know. But based on this experience, I give liners props.
Quit whining and move your %$# up that mountain.

Next

Who is online

Users browsing this forum: No registered users and 6 guests