Instructables

Step 2: Use a Pad

Picture of Use a Pad
Many of the big tough hikers or ultralight junkies out there spurn the use of the pad--as did I, until I got a bag that requires one. This is fine, normally; granite's as good as a box spring from my point of view.
But when you're in extremely cold conditions, and especially when sleeping in the snow, it's a must. This Big Agnes pad is my favorite, though it takes about a half-life of plutonium to inflate, but virtually any pad will do. Closed-cell foam is obviously better for hiking in areas where punctures are a risk, and many prefer the convenience of self-inflating thermarests. As long as you have one, it doesn't really matter.
 
Remove these adsRemove these ads by Signing Up
gen814651 year ago
What I've found to help keep warm is to put one of those thermal "space blankets" between my ground pad and my sleeping bag. By putting it shiny side up, it reflects the body heat back on to me. Do not put it inside your sleeping bag, as too much heat reflection will cause you to sweat, and that defeats the entire purpose. The space blanket should be available at just about any place that sells sporting equipment, and may be listed as an "emergency blanket". They are reusable if folded and cared for, and when worn out, can be discarded (or used for something else) and go buy another. They're usually just a couple bucks.

DO NOT use an inflatible mat. they leach heat into the ground

whitepinoy4 years ago
Too many years in Boy Scouts with military leaders led me to give this explanation. When sleeping outdoors the key to staying warm isn’t so much as the pad that you use. The key is layering. The earth sets off heat all year long. No matter what the outside temperate is the earth is going to be warmer or cooler depending on the season. So what we want to do is use that temperature to regulate the heat in our bed. The best lesson that i have every received for camping was from and Master Sergeant Army Ranger who told me that when you sleep it is key to place 2 layers below you for every 1 layer on top. With this technique I have camped in -20 degrees weather and stayed toasty. And yes I only wore a hat. If you wear clothing it is more likely that you will sweet at night and not be comfortable. The other thing is not so much the bag or whether or not you wear clothing to sleep in it is whether or not you have the right size tent. If your tent is too big you will never be able to warm the air in your tent and you will be cold. But, also if you are cramming 3 men into a 2 man tent you are going to get extremely hot (I have done this thinking I would freeze on night). There is more to say but I think you get the idea.
I must disagree with something you stated - though the earth gives off heat - it absorbs it as well, as in the case of body heat. - this is well known through out the camping/outdoor world. You layer or pad the earth side first and formost - to prevent body heat absobtion. Then cover.

I do like your layering idea rule of thumb - interesting. Your Sargent knew of the absorbtion of body heat by the ground. hence he told you about layering.  ie; padding on the ground side.

- Air pads do not do as well as a foam pad for insulating you from the ground from what i found.
Bjorno -chase-2 years ago
Air is the best insulator from heat... period. IF you inflate it properly, an air pad is far superior.
-chase- Bjorno2 years ago
Sorry Bjorno - but you would in-correct in saying so.  the reason is....

air doesn't conduct or insulate heat or cold very well. you need a conductor. or insulator. to either retain or dispurse heat or cold. Air acts only to be heated or cooled by the conductor/insulator 

Inslulation with too much air doesn't work - though in the same token - insulation with out air doesn't work that well either. you need both. to keep it light weight and to act as a conductor / insulator of heat/cold.

there are many scientific explanations on the web about this and you will find many newer type air pads have an insulator / conductor added - they are the more costly air pads. The insulator not only helps conduct /insulate but also acts as a self inflator for the air pad when it expands - drawing air into the pad as it does so.

hope this helps you.

to prove it - grab a pool float - go lay on the snow - you'll freeze your butt off.
Add an insulator condutor to both sides -  you stay warmer - add an insulator /conductor with certain size air pockets between the conductor /insultor you'll stay even warmer or be more insulated from the cold ground/snow.

but hey don't take my word or others about this - jsut use a air pad - if we find you frozen solid in the morning - we'll all know for certain
- what you say, perhaps isn't the best way.
I found out the hard way (at a camp in Nepal, -16 outside) that sleeping with lots of clothes on actually stops the sleeping bag from warming you up.
DireWolf3693 years ago
My military experiance sleeping outdoors has been good to bad over my 20 years. It is important to strip down as far as you can go. generaly T-shirt and shorts or underwear. Jacket and pants would go in the sleeping bag with me so my body heat would warm them and i would be putting warm clothes on in the morning.
I found that a poncho liner in my sleeping bag kept me warmer. The importance of something between your sleeping bag and the ground can not be understated. As well as keeping out of the wind. I learned that the by a night of shivering on a hood of a hummer during a cold snap in April. My light weight bag and poncho liner fell short.
Soldiers that get issued a new sleeping bag find that they come with a sleeping cap so that Soldiers can cover their heads when they sleep. It also allows the head to be exsposed and your warm moist breath to be expelled outside your bag.
Thanks for the post and the good comments.
nafinohan4 years ago
I like camping, but hate blowing into synthetic bags, so I'm partial to foam pads. In my experience, inflatable pads leach body heat even quicker than sleeping directly on the ground. Under-pad insulation is a must! For under-pad insulation I simply use a few sheets of newspaper. It really makes a difference. I always take some old newspaper along for anything from lighting fires to cleaning pots, packing fragiles, wiping ... er ... stuff, to sleeping on (preferrably before doing any of the previously mentioned).
Keep in mind the basics regarding insulation: The more trapped air pockets you have, the better the insulation. Air pads are bad insulators (only 1 air pocket), foam pads will insulate you better but are usually less comfortable. Hybrids (air with a packable synthetic or down fill) are the best in terms of comfort and warmth but are usually heavier. Another trick is to use a thermal/space blanket to insulate you from your sleeping pad. It will prevent some amount of thermal transmission between you and the ground/pad. Again, good writeup!
The one I'm pictured with is probably the best I've used--its only drawback that I've been able to ascertain is that it takes so long to inflate. It's full-size, insulated, 2 inches thick when inflated, and rolls up small enough to easily fit in a coffee can.
Pro

Get More Out of Instructables

Already have an Account?

close

PDF Downloads
As a Pro member, you will gain access to download any Instructable in the PDF format. You also have the ability to customize your PDF download.

Upgrade to Pro today!