Are sleeping bag liners BS?

I have a 35 degree bag, and was very cold on Rainier last year.  I don't want a colder bag as I don't cold camp a lot.  A Google search seems split on these.  Some say BS some say they work.  Curious if anyone has had a good experience and can recommend one?

Thanks.

All they do is twist up inside my sleeping bag...not comfortable to me.

Seems like a 35 degree bag would be wholly inadequate for Rainier.

FrankPS wrote: Seems like a 35 degree bag would be wholly inadequate for Rainier.

We were attempting a 1.5 day ascent.  Its hot as balls during the day in July so a colder bag was not needed as I did not intend on spending an entire night in the bag.  However my friend got sick and we never ended up making a summit push.  That meant sleeping 5 more hours which got cold.  

Agreed they tend to twist up and dont add a ton of warmth.  Usually it's way better to just bring an appropriate bag. However they do still make a difference in warmth and depending on the trip adding a tiny bit of insulation may be all you need.  

I probably use mine more often as a travel sleeping bag when I may end up sleeping at an airport or I'll put my sleeping pad inside of if if I'm car camping in warm weather which is more comfortable than sleeping directly on most pads.  

I have not been on Rainier.

that would be my concern with a 35 degree bag... the unexpected...

i find sleeping bag liners to help me in my older 20 degree down bag when the temps are actually 20 degrees outside my tent. a sleeping bag liner and a hand warmer thrown down by feet keep it nice and toasty.

Just wear a puffy and insulated pants inside your sleeping bag if you get cold.

Sleep in your jacket and even pants white a hat  and gloves. No need when you already have all of this insulation. Rock what bag you have but agree that a 35 degree bag is not appropriate for Rainer 

Most sleeping bags "ratings" are more like survivability ratings rather than comfort. The North Face bags have been doing a label on their bags for a while that kinda addresses the comfort vs survival rating. Liners unless you're car camping aren't worth the weight imo

Bring more Snickers bars. Feed the furnace to keep yourself warm.

Whether or not a 35° bag is appropriate for Rainier is a matter of preference, tolerance for suffering, and knowledge of how to keep yourself warm. Some people use a 0° bag in the middle of summer, some use a 20° bag in the winter. There's way more that goes into determining how warm you are than simply the given temperature rating of your sleeping bag.

You can rent sleeping bags from many of the guiding companies on Rainier. Whittaker Mountaineering is just a few miles outside of the Park.

Thanks for the info, and the concern about my choice in bag.  Uncomfortable on Rainier in the 35, yes.  Did I think I was going to die, certainly not.  The purpose of my question was to see if anyone thought they were worth it.  Seems like I should consider another bag, or rent one.  Thanks again for the feedback.

One thought comes to mind.  An ultralight pair of down pants weighs about the same as a liner and is more versatile since it would also work to wear around camp and worn with you're puffy in the sleeping bag will probably add more warmth than a liner would.  

I like mine, it gives a more cottony-sheet feel than having nylon stick to my skin if I get clammy. Not sure it actually adds any *, though. 

NorCalNomad wrote: Most sleeping bags "ratings" are more like survivability ratings rather than comfort. The North Face bags have been doing a label on their bags for a while that kinda addresses the comfort vs survival rating. Liners unless you're car camping aren't worth the weight imo

The label on the North Face bags looks an awful lot like the labels mandated by the EU for bags sold in Europe. There's currently an ISO standard for sleeping bags that takes into account comfort as well as survival, as well as differences between how men and women deal with cold.

Think of it as another layer. I’m a fan.

They work well, but they're not magical. Can help keep the bag cleaner, longer, too. Something like this is what I suggest:

https://www.rei.com/product/797114/sea-to-summit-thermolite-reactor-extreme-sleeping-bag-liner

Another option is to buy down pants and down booties. Some use two sleeping bags, one in another.

A 35 degree bag for Rainier just wasn't very appropriate in my opinion.

Hate liners imo.  They work by not breathing well and you wake up clammy.  If you only need a cold weather bag one a year just rent one. 

Very much like my reactor liner. But what really changed my life was a hot nalgene. 

grog m wrote: Very much like my reactor liner. But what really changed my life was a hot nalgene. 

put a wool sock over the Nalgene or use a single wall metal bottle. It will release heat more slowing and make it far more comfy for longer

I have an old -20 degree bag that performs more like a +45. For winter car camping, I pair it with a fleece liner and it helps a lot. I've never found the liner to be uncomfortable. However, for an application like Rainier, this wouldn't be worth it because the liner is big and bulky.