Sleeping Out in Winter
By Gene Ruane
Scouting November-December 1993
BECAUSE IT'S LIKELY that the temperature will fall to its lowest during hours of darkness, winter
campers need to pay special attention to sleeping warmly. Smart outdoors persons develop what some call
a "sleeping system."
Such a system includes both equipment and clothing you use when bedding down. Cold weather
enthusiasts often will spend more time on refining their sleeping systems than on any other aspect of winter
Adequate insulation, underneath as well as on top, is most important. In fact, insulation underneath
can be the more important of the two locations, since the cold ground can conduct heat away from you
much faster than the frigid air above.
So you must consider both insulation above and below in planning a winter outing. One night spent
shivering in a sleeping bag is likely to destroy your enthusiasm for cold weather camping. Conversely, the
snug warmth of a properly constructed sleeping system will confirm to the camper that he has successfully
met the challenge of camping out in winter.
Here are the key factors to consider in any sleeping system:
The sleeping bag. Most Scouts have a sleeping bag but few have one that is adequate for spending a
night in subfreezing temperatures. A winter-weight bag costs big bucks, and you don't need it for camping
in other camping seasons. So consider some cheaper alternatives:
* Use a bag within a bag. Two lighter-weight sleeping bags may be combined, one inside the other, to
achieve or surpass the insulating ability of a winter-weight bag. However, to be effective the outer bag
must be big enough to hold the inner bag and the sleeper without compacting the fill of either bag. It is the
loft of the fill that traps warm air and provides sleeping comfort. If the loft is squeezed out when the two
bags are used together, neither bag will provide much warmth.
* A sleeping bag liner is a good way to upgrade your system for winter conditions. It is designed
specifically to fit inside a sleeping bag, so you avoid the compression problem noted above. A liner is
customarily filled with goose down, pile, or other synthetic material to provide maximum insulation with a
minimum of bulk. A liner can be fairly expensive, but you can use it alone as a warm-weather bag.
* Improvise a liner with a blanket. Fold the blanket lengthwise to form an envelope into which you slide
feet first. Overlap the edges of the blanket to prevent drafts. Fold the bottom under to avoid bunching as
well as drafts, but leave enough room so your feet aren't cramped. Follow the procedure described in the
camping chapter of The Boy Scout Handbook. Be sure, however, to leave enough room in the bag for you,
your sleeping clothes, and the liner, without compressing the fill of your bag.
The sleeping pad. The earth acts like a huge heat sponge absorbing warmth from any object that
comes in contact with it. While this heat loss is often imperceptible to campers, they attempt to interrupt its
flow by placing an insulation barrier between themselves and the soil. Here are some suitable barriers:
* A closed-cell plastic foam pad at least 3/8-inch thick is ideal for winter camping. Open-cell plastic foam,
on the other hand, would have to be at least two inches thick to provide the same amount of insulation.
Also, closed-cell foam won't absorb water the way open-cell foam will, which means you can use the same
pad in winter and summer.
* A Therm-a-rest Mattress, or one of similar design, is a combination foam pad-air mattress and provides
superior protection. The foam prevents contact with the cold ground and also creates small pockets of
warm, insulating air. The mattress cover is waterproof and self-inflating. However, the cost of such
bedding is high, usually between $40 and $70 for a brand name, but sometimes less for a “lookalike" pad.
* Layers of newspaper inside a plastic trash bag act like a sleeping pad. The layers should be thick enough
to provide a good barrier between you and the ground. You may want to limit use of this substitute to car
camping, however, because carrying enough newspapers would add too much weight for backpacking.