Sleeping Bags

When selecting a sleeping bag a number of factors need be considered given the potential variations in temperature and personal preferences. A winter sleeping bag should keep you warm in almost the coldest of conditions while a summer sleeping bag should provide shelter and comfort a warm summer's night. The three season sleeping bag can be used in most conditions but is always best to over solve when it comes to keeping warm at night.

Generally, there are three bag styles with the mummy style the most popular:

• Mummy is a form fitting sleeping bag that tapers in width from the shoulders to the legs with little wiggle room at the feet. The tighter fit translates to less convective heat loss in the bag keeping the body warm at night. The term mummy comes from the esophagus style head that can be drawn tight around the head.
• Rectangular bags do not have a hood but are more spacious inside. They are little heavier and conduct heat out faster than mummy style sleep bag.
• Semi-rectangular sleeping bags are scored at the shoulders but taper towards the feet the semi-rectangular sleeping bags are little warmer and lighter than the rectangular bags.

Temperature ratings are prepared by the manufacturer and need close inspection. As rule of thumb solve for 10º lower than the most temperature you expect to have at camp. The typical rating systems across most bag manufacturers are the following:

• Summer space (40º to 60ºF, or 4º to 16ºC)
• Three season (20º to 40ºF, or -6º to 4ºC)
• Cold weather (0º to 20ºF, or -17º to -6ºC)
• Winter (-30º to 0ºF, or -34º to -17ºC)

Insulation determines the amount of warmth in the bag by providing dead air space for heat to retain itself inside the sleeping bag. Retain in as in trapping warm air versus transferring the heat out.
Beginning with the best, Down material is made from the feathers or plumage of geese or ducks underbody. This material provides the most insulation from outside temperature because of its "fill" power. Power being the amount of space measured in cubic inches an ounce of down will fill. Fill power goes from 500 in.³ up to 800 in.³ with a larger number providing the most insulation from the outside and retain even more heat from the body. High end bags begin to 700 fill and 800 fill in are earmarked for expeditions and extreme conditions.

The pros of down are excellent insulation, very light weight, compressible for packing, and a long life span. The cons are the manufacturing costs to sew baffles to hold the down into smaller areas; the excess plummeting of a creature's underbelly, and are very lumpy when it gets wet and has long drying times.

Synthetic materials go by a variety of names and have brand names like Polarguard. This material is made from a form of polyester fibers providing dead air space and light weight. But they are still slightly heavier and insulate slightly less than down.

The pros a synthetic material are lower manufacturing costs, and they do not absorb water, and will dry quickly. The cons are synthetic materials weigh more and are less efficient than down, have shorter lives, and are harder to compress pack.

Superthin fibers like Primaloft and Lite Loft are close to down for weight and thermal efficiency and packing compression without the wetness factor.

[ Back to top ]

Other Features

For colder climates, a hood allows you to insulate your head to slow heat loss. Well designed bags have zippers allow you to open the sleeping bag easily from either the inside or outside the bag. The bag should conform to your body with the proper amount of wiggle room that you desire. For couples who sleep next to each other, quality made sleeping bags can be adjoined together through the zippers of each bag. There are bags made for the size of two people that are larger and heavier than one or even the Sun with two small bags.

Bag care is important to prolong life in the bag plus keep the cleanliness on the high side. First, stuff the sleeping bag into its sack to reduce fiber damage in folding the bag. Secondly take the bag the stuff pack when stored at home and put into a breathable laundry bag. Follow manufacturers direct and for washing when the bag is dirty. Repeated washing its will break down fibers over time.

[ Back to top ]

Tips for Sleeping Warm

Highland Hiking has compiled this list of tips to help you remain warm in your sleeping bag at night:

• Before retiring to the sleeping bag, place a warm water bottle inside the bag.
• Change into dry clothing before you get into the bag.
• Wear additional clothing if necessary.
• Do some sit ups when you get into the bag.
• Stay away from the edges or siding of a tent that will be wet in the morning.
• Always use a sleeping pad to soften the lay and insulate you from the cold ground.

[ Back to top ]