Hey Folks

I get asked all the time which kind insulation fill is best for a sleeping bag for someone coming to Alaska. Like almost all these kinds of questions, the answer is pretty subjective, and I really don’t think it matters too much. What matters is that you make the decision that best fits your particular set of circumstances. That said, here are a few notes that may help you in your decision-making. I own both down and synthetic bags, and I honestly don’t find the type of fill to be the deciding factor in how I like a bag.

Pluses

Down:

* lightweight for warmth – Even the best synthetic fill can’t match down for it’s weight/warmth ratio.
* compressable – Down bags will compress down into a smaller size package than any equivalent synthetic bag.
* longer life – Down doesn’t break down like a synthetic material does, and so will generally, with reasonable care, last longer.
* comfort – Most people say down ‘feels’ better. I think it’s because t’s generally lighter, but I must admit, I do like down bags.

Synthetic:

* cheaper – a 20deg synthetic bag will be substantially cheaper than a 20 deg down bag.
* insulates when wet – synthetic fill reputedly don’t lose any, or very much, of their insulating properties when they get wet.
* dries faster – Down bags take a longer time to dry, and synthetic bags tend to dry reasonably quickly.

Minuses

Down:

* loses insulation properties when wet.
* dries slowly (I’ve had a bag get wet, and was impressed with how quickly it dried (overnight) – but definitely slower than a synthetic fill bag would.
* expensive.

Synthetic:

* heavier.
* less compressable.
* less durable. Synthetic filaments will break down over time, sooner than down bags typically do.

However, I have to point out that each of these is relative. A synthetic bag, soaked in cold glacial river, is less warm than a lighter weight but dry synthetic bag. And if your bag is wet, and the temperature drops to 32deg, don’t expect to be too toasty in it. It depends, of course, on many things, but how wet the bag gets is one of them. I’ve had a down bag get soaking wet, and I was actually surprised how warm I stayed, and how quickly it dried out – overnight. Further, in years and years of spending countless nights in the backcountry and camping in general, I’ve only had a sleeping bag get wet twice. For most people, this really isn’t, IMO, much of an issue.

How important each of these factors are will depend on a lot of subjectivity. I like a down bag that weighs less, and compresses down to almost nothing, because I typically carry a fairly heavy pack, weighed down with heavy bulky camera gear. The more weight and space I can save elsewhere, the better. Your milage may vary. I really don’t think it matters if you have a synthetic bag or a down bag. With reasonable care, you should be able to get years of use out of either type bag and your bag should almost never get wet in the backcountry.

One thing I will add that even with down fill, not all down is the same. 600 power fill down is not the same thing as 850 or 900 power fill. Generally, the higher that number, the better the down quality is: it’s warmth/weight ratio is better, it last longer, breaks down less, and is more compressable. Synthetic filaments are similarly not all equal, so the question of down versus synthetic is somewhat incomplete.

Lastly, if you go for a down bag, it’s hard to beat Western Mountaineering and Feathered Friends they specialize in down, and I don’t know of anyone who makes a better product. Marmot would be close behind though, as are Montbell. Mountain Hardwear make some nice stuff, but I think they should put a full length zipper in their lightweight bags. I also think they overrate the temperatures of their bags a bit .. but so do most companies. The North Face make great bags.

For synthetic fill bags, Sierra Designs make a few nice bags, and the REI brand bags can be a very cost effective choice. They’re not too bad at all, and more affordable than most, though their temperature ratings are also, IMO, suspect.

Either way, hang your bag or stuff it in a cotton sack, not compressed, when it’s not in use. I handwash my down bags, and try to take good care of them.my North Face Foxfire is still a great bag, and it’s 13 years old. I’d also suggest not over-compressing even down bags when you go hiking. The compression sacks you can buy are great, but i’m not sure it’s in the best interest of your bag to compress it too much – even down can only handle so much.

Here’s some great advice for looking after a down bag:
Western Mountaineering Webpage.

I hope this helps. The main thing is to not stress too much over it, and know that most bags are going to be just fine for most people. Buy one, or use your old one, and enjoy the backcountry!

Cheers

Carl

Hey Folks,

I think a 20deg bag is essential for a summer trip in Alaska. 32deg bags, and warmer, often aren’t warm enough for alpine trips here. In fact, a 15 deg bag is even a good idea. it varies a lot with the individual, and also with the temperatures for any given trip, obviously. Temperatures can easily dip into the 32deg range, even in mid-summer, and while this isn’t too often, it’s not uncommon. If you’re planning a trip with for the shoulder season, such as late Aug/early Sept, even a 10deg bag isn’t overkill.

A good rule of thumb is your bag will keep you warm to within 10 deg of it’s rating. For example, a 20deg bag is great at 32deg. At colder temperatures, you’ll just as likely be uncomfortable and not sleep well. Not all bags are the same, and you’ll often find one company’s ratings to be quite different to another’s.

My experience has been that Western Mountaineering make great bags, Feathered Friends as well. Both are pretty pricey. I do like The North Face bags. I have a 12 year old Foxfire, rated about 10deg, which still is a great bag, a little heavier than some newer options, but I love it. Generally, I like a down bag, but I don’t think it’s critical – synthetic fill bags have their own set of advantages. I’ll write about that in another post.

Another thing is the length of the zipper. I like a full length zipper. Some of the bags these days have a half-length, as companies try to save ounces here and there. Mountain Hardwear Phantom bags are a good example of this – if they had a full length zipper, I’d highly recommend them. But if the temperature warms up, and you’re in a 20deg bag, it’s way too hard to not overheat in a bag that you can’t unzip all the way down. My feet burn up pretty quickly when the weather is down there, so I like a bag where I can open up the lower end of the zipper. Some folks this may not matter as much for.

Some people argue against wearing long underwear in a sleeping bag, as your body heat is supposed to warm the air inside the bag. Layers, even a single layer, of clothing can mean the air in the bag stays colder, and you lose body heat.For extra insulation, throw a fleece or heavier jacket over your bag, rather than adding layers to your body. Another great idea is to heat some water on your stove, pour it into your Nalgene bottle, seal the lid properly, and use it as a hot water bottle.

Sleeping pad designs have improved a lot in recent years. The first question is 3/4 or full length. I generally take a 3/4 length pad, just to save weight, but the added insulation and comfort of a full length pad is helpful if the weather gets rough. I’d recommend the ultra-lite series, the yellow pads, as they save a lot of space in your pack. I can fit my 3/4 length pad, my 20deg bag and all my clothes in the bottom section of my backpack. If you have a bad back or need some extra comfort, try out the other pads. The Ex-Ped is a nice pad, with down fill, providing more insulation and padding to give you both added comfort and warmth. If you think you’ll be camping on a glacier at all, another, and cheaper, option is to bring a second pad, like a cheap all foam pad, like the Z-rest that you can place under your thermarest.

Whatever you do, as always, give your gear a good workout before you head out on a week long trip.In the store, get in the bag, get ion and out of the bag, roll over, move around, make sure you’re comfortable. Don’t get so hung up on numbers and stats like weight, and size, etc – it doesn’t matter if your bag weights 12 ounces if you can’t sleep in it. Do the same thing with your pad. And think about where you’re going hiking, what kind of terrain are you going to be in, what kind of temperatures are likely, is the ground rocky or grassy, wet or dry, and so on. Do you tend to feel the cold more than your family/friends, etc? If so, that will affect the decision of which bag and pad is right for you.

Cheers

Carl