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sleeping bag question
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Kiel Senninger
(Kiel.S.) - F

Locale: San Diego
sleeping bag question on 09/19/2013 22:43:52 MDT Print View

I've got an older REI Polar Pod (bought in 2008). Regular size, synthetic, mummy style. REI says it's a 20*F bag. I'm not a big person, about 5'9" 150lbs. Definitely not top of the line or lightweight. I bought it when I first got into backpacking and before I knew about what was out there. It's served me well enough to not drop $400 on a new bag. However, I've noticed that the fabric on the inside of the bag gets really cold. And when my legs touch it, it's pretty uncomfortable. I noticed it for the first time a couple years ago when the temps got down below freezing. I used to just sleep in boxer shorts, so I bought some lightweight Patagonia capilene long-underwear. It seemed to work alright, but not on my last trip. I was around Miter Basin 9/8-10. It was windy, but I don't think it got below freezing. My legs got cold enough from touching the fabric that I had to wrap my nano puff around my thighs. The air in the bag is warm enough, but the fabric is super cold. My go to sleep setup is a thicker long sleeve REI base layer shirt, the capilene long johns, regular cotton socks, beanie (if cold enough), light fleece if needed, and if I'm really cold, the Nano Puff. Do you think the cut of the bag is too tight? Poor design? 20* is too ambitious of a rating for this bag? Is this a common problem with sleeping bags? I'm hoping to learn something from this that can help me avoid a similar problem when I do take the plunge to a higher end bag.


Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: sleeping bag question on 09/19/2013 23:12:13 MDT Print View

First of all, there is the discussion of synthetic versus down insulation. As a general rule, if they are stored properly, down will outlive synthetic. Down won't hold up to moisture as synthetic will. If you were in a slightly cold, dry situation, I would think that down would be a better choice. That's not saying that the synthetic bag is junk, but it is possible that yours is not as good as it used to be. Some synthetic bags will seem to lose loft worse than others of the same brand. We don't know what the current loft is, so we can't say about yours. Some bags will lose loft if they get dirty from use.

Second, no matter what kind of sleeping bag you use, you must be able to maneuver it to some place where you can preserve what little warmth you have left. So, were you in a tent, or under a tarp, or just out under the stars? Was there a wind block? Were you in a valley depression where the cold air collected at night?

It is also possible that you are older than you used to be when you bought the bag. People tend to have their metabolism slow down with age. You can offset some of that by eating a hot meal before you try to sleep. If you consume too much hot liquid, then it will feel good for a while, but then it will wake you up in the middle of the night when it is even colder.


And E
(LunchANDYnner) - F

Locale: Pacific Northwest
More info on 09/19/2013 23:12:56 MDT Print View

Need more info. Were you in some sort of shelter (tarp, tent, bivy, etc)?

EDIT: It seems Bob beat me to it.

Edited by LunchANDYnner on 09/19/2013 23:23:07 MDT.

jerry adams
(retiredjerry) - MLife

Locale: Oregon and Washington
Re: sleeping bag question on 09/19/2013 23:15:13 MDT Print View

synthetic bags lose their loft over time, depending on how much you compress it

have you used it a lot? compressed it pretty tightly? what's the loft, like where you're cold especially?

Kiel Senninger
(Kiel.S.) - F

Locale: San Diego
more info on 09/19/2013 23:23:31 MDT Print View

The bag is washed after each trip and stored in a large stuff sack where it's not compressed.

Both nights I camped near a lake (Sky Blue Lake and Cottonwood Lake #4), but elevated. I was in an SMD Lunar Solo. I tried to predict the wind and set up with some natural shelter, but the wind still ripped through my tent.

I was cold both nights, but more so the second night. This is probably because I had gotten sick earlier that evening and hadn't eaten much. Would this make the fabric feel colder to touch? or just a general difficulty warming up? Overall, I felt warm just not where my lower body was touching the bag fabric.

jerry adams
(retiredjerry) - MLife

Locale: Oregon and Washington
Re: more info on 09/19/2013 23:27:47 MDT Print View

How many trips have you taken? Do you compress it a lot when it's in your pack?

I hardly ever wash my sleeping bag. e.g. I do 100 nights without washing. Maybe this is an example of what you shouldn't do : ) Maybe when you wash it it hurts the loft?

How thick is the insulation? It should be maybe a couple inches to be 20 F.

Rick Adams
(rickadams100) - M
bag on 09/19/2013 23:31:56 MDT Print View

I used to have that bag. My wm megalite 35f is much warmer. It is simply not close to 20f imo.

Kiel Senninger
(Kiel.S.) - F

Locale: San Diego
loft and compression on 09/19/2013 23:32:13 MDT Print View

Just checked the loft. It feels thicker at the shoulders and zipper than it does in the middle of the bag and opposite of the zipper. Right where my legs are... this could explain it.

The bag is super compressed in my pack, but uncompressed in storage. I only get it out like maybe 14 nights a year and that's not a continuous 14 nights. So for the most part it sits nice and fluffy in my closet.

Is it easier to keep the loft even in a down bag vs synthetic? Or is it just dependent on the quality of the bag?

Edited by Kiel.S. on 09/19/2013 23:34:03 MDT.

Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: sleeping bag question on 09/19/2013 23:39:02 MDT Print View

I've never had a synthetic sleeping bag that would hold up with great loft beyond the age of five or eight years. As a result, I switched over to goose down a long time ago. Part of it is because of weight, but a lot of it is because down can be compacted and then fluffed up without damage if you do it right. Synthetic would take a bigger hit over time.


Justin Baker
(justin_baker) - F

Locale: Santa Rosa, CA
Re: Re: sleeping bag question on 09/19/2013 23:45:31 MDT Print View

I had a mountain hardware lamina bag get cold on me after about 80 nights. I used it all summer/fall and didn't notice until I took it on a shoulder season trip in at 4k feet big sur where it cold way colder than expected... it sucked.
Down is much more economical in the long term.

Franco Darioli
(Franco) - M

Locale: @Tarptent
sleeping bag question on 09/20/2013 00:43:47 MDT Print View

It is possible that the leg area was thinner to start with or that it has had more compression.
If you bend your legs when sleeping that could put pressure there .
Apart from that :
"This is probably because I had gotten sick earlier that evening and hadn't eaten much. Would this make the fabric feel colder to touch?"
Not sure why but many miss the fact that bags (or clothing) are not warm by themselves, you produce the heat , the better the insulation the more of that heat is retained.
Now to produce heat, you need fuel.
Food is your fuel.
Maybe that is why we use the term "calories"...
(OK, that is easy for me. It comes from the Latin word for "heat"...)

eric chan
(bearbreeder) - F
pods on 09/20/2013 00:46:59 MDT Print View

synthetic insulation will degrade with use ... generally IME expect to lose about 5F in the first 1-2 years and 10F after that with decent use

some insulations last a tad longer, APEX is the leader currently ... of course the price for those bags is a bit more expensive

the other thing you have to remember is that the polar pod 20 is a pretty cheap bag, even in terms on synth pricing ... back then REI sleeping bags may not have been accurately (EN) rated ...

but dont worry all is not lost!!!

if you feel you didnt get good value and its breaking down before its supposed to, simply take it back to REI ... despite the policy change gear purchased prior to june this year should have the unlimited old warranty

course certain "moral" BPLers may spew fire and brimestone at you for your "decadence" ... but whats BPL without some intraweb holier than thou

the other thing is that what you eat and how warm you go to bed absolutely make a difference ... eat fatty food, dont skimp on liquids, and if your bag is cold do situps till warm ...

more info ...


Edited by bearbreeder on 09/20/2013 00:49:28 MDT.

Stephen Komae
(skomae) - MLife

Locale: northeastern US
Re: pods on 09/20/2013 00:59:07 MDT Print View

Temperature rating... Many sleeping bags are rated extremely optimistically, with the degree rating following the name of the bag usually around the EN lower limit rating. For comfort I would add 15 degrees to that and given that the bag has already seen some decent use, the synthetic insulation will also not be quite as effective as when new.

James Marco
(jamesdmarco) - MLife

Locale: Finger Lakes
loft, compression, ratings on 09/20/2013 06:42:15 MDT Print View

Hiya Kiel.
Well As others have said, synthetics do not last anywhere near as long as down. Synthetics can be done badly or well done. Even the best of these only last about a year(15-30 nights) before they start degrading. I usually buy a 0F synthetic, not because it is warmer, but because it will last 10 years(360 nights) before it goes to 32F; average loss of warmth is about 3-4 degrees per year. Keep it CLEAN. Body oils, dust combine to form a low insulation value on synthetics and down. Some people sweat very little, some a lot. It depends on your metabolism. Down will typically last 20+ years assuming the same usage.
Synthetics only advantage over down is when wet or very damp. They are a bit stiffer than a natural down fiber. But, they will degrade quicker if you compress them. The harder, hollow fibers usually kink/compress together and do not have the resiliancy to bounce back. Down is mostly air and has some "stickiness" to it, so compressing it simply squeezes the air out; 30sec of shaking to overcome the "stickiness" will restore most of the loft and body heat will cause the fibers to return to their natural shape. Down will withstand higher heat (though not the shell/zipper.) Anything up to 200F(~95C) or so will not hurt it. It simply fluffs up more. This is from direct experience with flie tying. STEAM heat is OK to restore a matted fly be it a fluffy streamer or a dry. Every tight compression of a synthetic causes some loss of loft. You really shouldn't compress them a much less than 5:1. More is damaging to loft on synthetics. Typically 10:1 is OK with down.

The EN ratings all use some sort of covering over the manikin used as a heat source. We know that UL long johs are better than shorts. Mid weight are better than Lights. Heavy weights are better than Mid weights. Want to guess what is used during EN ratings? There is no weight spec. There are many out there that do not expect to need any coverings. It is all subjective anyway. Some people sleep cold and need a 10F bag for 32F. Some sleep warm, and need a 40F bag for 32F. It is very difficult to be accurate with temp ratings. US system differs. Even the loft (which is rated at EN800FP MAX, even Eider down) is different(US rating is 900FP.) The EN ratings are better, but still leave the manufacturors plenty of wiggle room.
Anyway, this is your subjective experience. All I can do is recommend some methodes to keep you warmer.
1) Wear Long Johns to bed. These will add minimal bulk and weight and give you the extra warmth you are looking for. Long, sleeping socks, too.
2) Drink a cup of hot cocoa before bed. Use the bathroom, then turn in. This will add "some" warmth without too much liquid forcing you to make midnight runs.
3) Eat a candy bar. Chocolate is prefered because it has fats & oils (lipids) for long term fuel and slower digestion...and sugar to help you get warm.
4) If you get cold, do some sit-ups. Waking metabolism is faster than sleeping burned exercising will warm your whole body eventually.
5) Heat a bottle of water and put it into the bag.
6) Put any extra cloths (damp cloths are OK) in your bag. Though this may cause loss of loft with down, it will act as extra insulation and reduce air pockets making your bag easier to warm up.
7) Insure you have good ground padding. I assume you do. But, 1/4 of CCF pad is no where near as warm as a 3/4" NightLite. NeoAir's are not as warm as Exped Down Mats or Stephenson's DAMS. You should use the correct one for what you expect and how you sleep.
8) Sleep under a lower tarp or tent. IR acounts for about 10 Watts of heat. This can be held with a roof, but it needs to be fairly close to you. No more than a foot away or it starts loosing effectiveness. Closer and you have a lot of condensation. This depends on your conditions, of course.
9) Not recommended for long term, but for a night or two you can cover your head under your bag. Down will degrade with condensation, but it will warm you for several hours(3-6.) Synthetics get wet but perform similarly. Make sure you can dry your bag in the morning, though.
10) Light a candle. The psychological effect is worth it in a tent or under a tarp. Be carefull. It might add another degree of warmth in a small tent.
11) Choosing ground by avoiding ridges, mountain tops and fields. A pine tree often makes a good shelter, blocking winds and draughts. Pile forest duff under, around your bag. It will add some warmth. Avoid shore lines near lakes and rivers. Aviod valley floors.
12) If a fire is an option, build one. You may need to stoke it several times over the night, though. Waking metabolism is faster than sleeping metabolism, so, it may be uncomfortable with waking every couple hours, but I know it helps.
13) ANY dry clothing you have, put it on.
14) Put your pad inside your sleeping bag, if you use an inflatable. It will benefit from edge losses and be warmer to sleep on. It also reduces the volume inside a bit. Be carefull NOT to compress your bag, though.

There are probably some others that I forgot. I typically head into the ADK's in spring and fall with a too-light bag. These "tricks" work.

peter vacco

Locale: no. california
Re: sleeping bag question on 09/20/2013 07:37:12 MDT Print View

the weight and quality and intended usage of the bag sometimes also relates to the weight of the materials used in it.
along those lines, a very lightweight material used to line a bag will feel warmer, simply because when your leg hits it, there is less mass for your leg to bring up to temperature.

if you take this theory to extremes, and visualize a bag with a liner made of really stout plasticized fabric, you can imagine that it would be a nasty thing to sleep in, no matter it's insulating value.
i think the theory also explains why those ultra light, ultra poofy western mountaineering bags feel so great at home, but some of the lighter ones will be found to lack the guts for cool weather work.

so, bottom line, the cheaper / heavier bag liners will feel colder to the touch.

just my op.


F. R.
(fugitiveride) - F

Locale: Syldavia
Too tight in the legs on 09/23/2013 15:23:33 MDT Print View

I find mummy bags too tight in the legs. I feel so contricted.

Can anyone recommend something? I've been thinking of some of the quilts, but even they get pretty tight around the feet.

James Couch

Locale: Cascade Mountains
Re: Too tight in the legs on 09/23/2013 17:33:08 MDT Print View

Look into the Big Agnes sleeping bags. The Lost Ranger or similar models are much wider in the legs than a typical mummy.

Paul Andronico
(Jakesandwich) - MLife

Locale: S.F. Bay Area
EE Quilt on 09/23/2013 19:15:28 MDT Print View

F.R., my regular/wide Enlightened Equipment 20 degree quilt has plenty of room in the footbox for me. Having used it on three trips now, I love using a quilt and would only consider using a mummy bag for winter use. For reference, I am 5' 10" and 180 pounds, with size 10 feet. Tim at Enlightened Equipment may be able to make a custom, larger, footbox if you need something even wider. Good luck on your search!