Sleeping Bag Size Question - Length

Hi all. I'm looking at purchasing a new bag. I'm 5'10" and should fit comfortably in a 6' bag. The problem is when I sleep on my back I like to point my toes down (away from my head). In my current bag they touch the end of the bag and somewhat restrict this movement. It's not a show stopper, but is slightly annoying. I'm toying with a 6'6" bag but I've heard the extra length will create a dead air spot which may cause cold feet. And the longer bag is more expensive, takes more room and adds more weight. Any thoughts on this? Thanks in advance for your help.

I never realized until I developed plantar fasciitis last spring that when we relax our muscles in sleep, our feet go into the pointy-toe position. (I've had to wear a night splint on the affected foot to prevent the plantar fascia from contracting--painfully--during the night.) That means that when we are stretched out full length and relaxed, we're about 1.5 to 2 inches longer than our height measured while we're standing! I'm 5'4", but if I stretch out full length and relax, my toes do touch (barely) the bottom of my short size (5'6") sleeping bag.

I always sleep curled up on my side in the fetal position, so this is no big deal. But those who stretch out full-length to sleep will probably need a bag designed for someone 2 inches taller than their height. In your case, at 5'10" you are right on the borderline. Only you can make the decision whether that extra toe room is worth the extra weight and dead air space. If you were an inch taller, no question, you'd need the long bag.

Cold caused by extra length is only a factor if you are pushing the limit of your temperature range, or doing winter camping. I prefer to keep to the shorter length because I do not like carrying the extra weight. But I, like OM, am a side sleeper so it really is not an issue. If you choose the longer bag, you can always throw some extra clothing in the foot. If the short bag bothers you while testing it in the store, it likely will be really annoying on a trip. A more relevent consideration is to be sure your sleeping pad is long enough (I use a short pad but then bring a 2x2 square of blue foam to put under my feet). Having feet directly on the ground will make them colder than any dead air space of a longer bag. Different brands of sleeping bags have different lengths - have you checked into a different brand? Maybe you will not be on the borderline between sizes then.

I have found that this "get a shorter bag" theory a bit specious. True, there is extra airspace in a longer bag, but once it warms up, as long as you aren't thrashing around and letting cold air in constantly, I doubt you would notice much difference.

If you are worried about getting cold, here are some things you can do: Make sure you have a decent pad. In winter, I use two-a full length inflatable Thermo-rest and a full length Ridgerest. If I get cold, I put on socks, a beanie or balaclava and gloves. Eat before going to bed; running out of fuel is a big reason you will get cold. I keep a Clif Bar or something similar near my bag within reach. If I wake up cold, I will eat about half a bar and within a few minutes, I start to warm up again. It is surprising how well that works.

Get a warmer bag. Seriously, if having a longer bag is going to make you cold, your bag isn't warm enough, no matter what. Plus in winter, having room for extra socks or even your boots or their liners if you have doubles, is a good idea.

I can't speak as an authority here, since a regular length bag works fine for me (I'm not overweight, I'm undertall.) Like Tom, I'd think that the extra length wouldn't be a big deal. Bags aren't stiff; if your toes aren't holding it open, I would think the extra toe area would just kind of collapse and there wouldn't be a large void to heat.

However, one thing I can think of, if your feet do get cold because there's too much room, would be to carry a pair of down booties on cold nights, which would both fill the void and put a layer of down around your feet.

Good point Glenn. I have a pair of down booties and forgot to mention them in my post. In a bag, socks works just about as well once you have warmed it up. Remember, bags just retain your own heat, so the more you generate, the warmer you will be, all other things being equal.

When it gets below freezing, there are quite a few things you may want to protect from freezing or at least keep warm in your sleeping bag--camera battery, water filter, fuel canister.... (Clunk clunk). In really cold weather, you may also be wearing all or most of your insulating clothing inside the sleeping bag. In other words, that extra room may be a good thing, and not just for your toes!

I'm not that keen on wearing a lot of clothes inside a bag. I've done it and it's just not that comfortable, at least for me. I do wear my long underwear (Capilene) but anything more than that, I try to avoid. Although I have worn socks, booties, gloves (light liner style) and a beanie, plus tossed my parka over top. My parka, as you can see, is about half the size of a bag anyway, so it helps. It is a serious winter parka. I also have an overbag, but now I have a warmer bag (-10F) so the overbag will probably stay home this winter unless I go somewhere really cold.

What if you just throw a pack of Hot Hand in the extra space?

I assume that is a chemical pack? If so, I wouldn't do it. Some of them generate a lot of heat and might damage the bag. Not sure whether my concerns are justified, but not worth it to me to find out.

I am just a smidgen short of 6 feet tall and went with a long bag and I would not do that again. I have a WM Megalite Long and it is a wonderful bag but the extra length is dead air space that has to be warmed up. Recently I borrowed a WM Ultralite regular length for a trip into the Sierra's and it was significantly warmer for me. I am a COLD side sleeper and the length was just fine. I am going to make a down quilt, actually, my wife is going to make it and try that out with all 4 inches of loft on top!

If you want a 0 degree quilt that will work.... 2.5 is adequate to about 20-25F, give or take.

I have a 0 degree underquilt with 4 inches, no way to use it when it's above freezing - you'd roast.

Thanks to all for you help,





CJC - thanks and this is particularly apropos as the #1 option on my list right now is the WM summerlite. I realize you are a side sleeper but I wonder if you notice if your toes can touch the bottom (when pointed) when you lie on your back? I switch between side and back sleeping. I'm having a hard time finding a WM bag here in the area to try out. Thanks.

I use the hand warmer, sleeping bag warmers, toe warmers... well you get the idea - in my sleeping bag all the time - these are the oxygen packs (chemical reaction with oxygen to create heat.) I do NOT use the hand warmers that use butain or that you lite (solid fuel) in my sleeping bag (though I do use the solid fuel ones in my jacket pockets.

I am sure they touched but I was to worn out to really notice or care. First long trip in yrs and it was wonderful! I stretched in the bag when waking but didn't have any issues with the length.

The WM Ultralite I used this summer was very nice. My Megalite was in getting repaired and having 2 oz of additional down added to it. I will take that to Zion NP in October where we anticipate the lows to b in the mid to low 40's. Up at Guitar Lake this summer it dropped down into the mid 30's and I was zipped up in the Ultrlite and very comfy and that's with long johns on. I am a really cold sleeper and that is why I was looking at 4 inches of loft on the quilt. I have also dropped 25lbs since the first of the year and I am thinking the Megalite might now b mega big on me. I will know in October.

I have a friend who says she is a "really cold sleeper" who uses a 0 degree bag all summer. She has metabolic issues....

A fellow I took on his first backpacking trip in decades shivered through a 40F night in a 20F bag, and went to the doctor - it turned out that the rash he was sporting was a staph infection on his skin and that compromised his ability to self regulate.

If you have really good bags (WM is widely known to be conservatively rated) and are needing to use a lower rated bag, and you are unaware of physical issues that might be causing this, you should go to a doctor for a full workup, IMO. There should be (given a normal human physiology) no reason for 4 inches of loft unless you are winter camping.

I thought the same way when I started out - I am a cold sleeper. But you also need to eat and hydrate properly, and exercise regularly to maintain a good working metabolism. My ability to thermoregulate improved by leaps and bounds when I paid attention to these things.

I am a really cold sleeper. I practice ALL the suggested stuff to sleep warmer. I am still a really cold sleeper! Take the temperature ratings (as well as loft in inches) with a grain of salt. The design of the bag also plays a role. So be sure to get a bag that fits. I have a WM Super Antelope/short - and I still have to stuff some clothing inside to fill in the dead air space in order to sleep warm enough. I bought this bag before they came out with a woman's specific version. In the last few years I have seen a much better selection of sizes (both length and circumference). There really is a lack of choice for small skiny people.

I also find that I have to switch to a better sleeping pad for the shoulder seasons when it gets colder. Much of my "cold" is really from underneath, not a function of the loft of the bag. Hats also really help. When it gets below 35-degrees I have to put on a balaclava under my regular fleece hat. I actually have a detachable hood from a down parka that I use when it gets near the lower limit of the bag. Feet are also a big factor- maybe just adding down booties would help.