Sunday, November 2, 2008

Lightweight Sleeping Systems (bags, quilts, pads, bivys, etc.)







One of my favorite backpacking topics is “sleeping systems”. To the inexperienced or uneducated, “system” may seem like a bit of a stretch to describe what most people assume to mean merely a sleeping bag. The reality is, there are better (warmer and lighter) options than just a sleeping bag and this is one of those issues you have to try to believe as many people simply cannot fathom “less” being “more”. Cold weather also seems to be a very quick way to evaluate whether going lightweight was a smart idea because getting cold not only can be devoid of fun, but it can also be life threatening. Lightweight backpacking requires an educated consumer who is willing to make smart choices based on their experience and environment.

A sleeping bag is a plenty decent option when sleeping in the wilderness. Unfortunately, it isn’t a terribly efficient system. First off, the mere pressure of your body on the bottom portion of your sleeping bag does nothing but compress whatever insulation you are using to keep you warm. Being that warmth comes from loft, whether it is down, synthetic, pine needles, or whatever, no loft equals no warmth no matter what it is. With that said, and you guessed it, the bottom part of your bag serves pretty much no function other than dead weight – so why carry it. Sleeping bags are also constrictive and no doubt users have been known to fight all night with a zipper to be comfortable. Lastly, sleeping bags often trap dampness, both inside the bag from the user and outside the bag from the environment. If the bag gets wet, the loft may be degraded. If the loft is degraded, so will its ability to keep you warm. Simply put, a sleeping bag is an option, just not necessarily the best one.

A quilt is an excellent replacement for a bag and ensures you have only what you need to stay warm. Without the unnecessary weight of the bottom portion of your sleeping bag, by default you just lightened your load. By definition, and much like your bed at home, a quilt is designed to lie on top of you instead of going completely around you. When fit properly, it drapes around your sides which traps warm air just like the bundling effect of a sleeping bag. Most backpacking quilts also offer a footbox to keep your feet in place and help keep you warm. Insulation choices range from down to synthetic with synthetic winning out in wetter climates and down tending to be warmer and lighter overall.
Several manufacturers make very good quilts which are also very lightweight. These include Nunatak (http://www.nunatakusa.com/), Jacks R Better (http://www.jacksrbetter.com/), Backpacking Light (http://www.backpackinglight.com/), Feathered Friends (http://www.featheredfriends.com/) and others. If you really like the bundling effect of a sleeping bag, try the Sleeplight offered by Gossamer Gear (http://www.gossamergear.com/cgi-bin/gossamergear/sleeplight.html) which is essentially a sleeping bag without insulation on the bottom. Being a person much taller and wider than others, I decided to go with the Caribou sleeping bag from Western Mountaineering (http://www.westernmountaineering.com/) which is just slightly bigger than the other quilt options listed above, but in some cases, it is lighter. The zipper was removed, saving some ounces, and two elastic straps were sewn on to cinch it to my sleeping pad. It functions extremely well in cold weather as I intended - as a quilt.
I should mention some people use a 3/4 length bag or quilt especially if they have warm upper layers as it further reduces unnecessary pack weight.

The next part of the sleeping system is a good ground pad to take out floor bumps and to provide insulation from the cold ground. Many people seem to think they need expensive inflatable pads and mattresses to be the most comfortable. The reality is, an inexpensive foam pad has a higher “R – value” (measure of thermal resistance), than most fancy and expensive options. Personally, I find foam pads to be a little more comfortable too as they don’t sit up so high and I don’t feel like I’m trying to sleep on a rubber raft. Because they are lightweight and fairly easy to carry, many people use them as a backpack frame of sorts by placing them inside their otherwise frameless or internal frame backpacks. Some manufacturers are putting things such as down feathers or special gels which have low freezing points in their pads. There is some debate as to whether these methods work, but not of any debate is the fact that these options are always more costly and heavier than a simple foam pad.


When picking a pad, pick one which is about the size of your torso. This may seem counterintuitive, but the reality is your legs don’t contact the ground in the same manner as the rest of your body and they also don't get cold as easily. Without a full length pad, you can save valuable weight. I’ve also found using my pack under my legs accomplishes the same task and uses something that would have otherwise just been lying around. Part of being successful at lightweight backpacking is using all your resources to their fullest extent. Gossamer Gear is one manufacturers who maintains several options for foam pads http://www.gossamergear.com/cgi-bin/gossamergear/pad_matrix.html.

The last part of the sleep system is a bivy made of a waterproof bottom (such as SilNylon) and breathable and water resistant top (such as Pertex). The bivy will help bundle you like a sleeping bag, but it will also allow you greater movement as it is cut larger than a standard sleeping bag which works perfectly for active quilt sleepers. It will also ensure your quilt doesn’t get wet which allows your loft to stay intact and that your body condensation can escape through the breathable fabric. Backpacking Light (http://www.backpackinglight.com/) offers some of the lightest bivys. Some manufacturers, such as Integral Designs (http://www.integraldesigns.com/) offers bivys made of eVENT fabric which allow the user to forgo the need for a conventional shelter and instead stay warm and dry sleeping under the stars.

I’ve used my system in below freezing temperatures and the entire system weighs far less than most sleeping bags and offers me much more comfort and flexiblity. I was personally shocked to find out that with merely a base layer of merino wool that I needed no other warming layers despite the cold temperatures. It is also worth noting that the choice of your sleeping system and its warmth rating should not go overboard because users should consider any clothing items carried as part of the system. For example, a sleeping system doesn't necessarily need to be improved if the user is cold at 30 degrees but can be plenty warm by adding a jacket buried in their back. Lightweight backpackers need to utilize all their resources as otherwise carrying something rarely used serves little greater purpose than dead weight. Much like an empty backpack can be used as a sleeping pad for your legs, a jacket can be used while sleeping and socks make excellent gloves in a pinch.

7 comments:

Anonymous said...

I wish I had found your blog BEFORE I dropped $270 on my Marmot bag. I had the exact same thought - that it makes no sense to have expensive 850+ down under you when you sleep since it's just getting compacted into nothing. Why doesn't anyone make a bag with down on the top and an integrated foam pad on the bottom? Anyway, this is my first high performance bag (it is literally light as a feather) - I haven't owned a bag since I was a kid and back then it was made out of super heavy cotton and polyester. I am excited to try it out. I'll be in a fairly warm climate but very humid and rainy. We'll see how it goes. Love your blog - thanks for all the useful links!

-equiliberate.org

Anonymous said...

Big Agnes makes most if not all of their bags with integrated pads in the bottom, not sure that all their gear is SUL though.

Jolly Green Giant said...

Very true. Big Agnes is a great manufacturer, but not quite UL. Some of their products fall close to the "light" category. Course, comfort is important and I think everyone makes value judgments between weight and comfort. If comfort can be achieved lighter, than that's the best option.

Thanks for stopping by.

Jakson said...

I have enjoyed reading. Nice blog. I will keep visiting this blog very often.

Tom said...

Getting some good quality sleeping on a backpacking trip is always difficult and is what normally puts me off. I end up coming back more tired than when I left. Hopwfully with these new products out I might get some shut eye

matt said...
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Jolly Green Giant said...
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