For years North Americans have been awash in information about the need for and composition of bug-out bags and get-home bags. To be practical, such bags must optimize weight and bulk. While tents and tarps make great shelters in most situations, consider the following.

You keep your in-case bag on your motorcycle because you travel to remote rural areas. During a trip in the intermountain West, an unpredicted snowstorm overtakes you. Your bike slides off the road and down a moderate slope, coming to a stop near a small outcropping of rock. You dismount to assess your situation. The big bike is hopelessly stuck in mud and snow—more importantly, it can’t be seen from the road because of the hill’s angle. You know the area enough that traffic is unlikely, but an overland hike of 3 miles will get you to a small town where you can wait out the storm. You should make it before sundown.

When you’re halfway to the town, the wind doubles, causing you to lean forward into it. Then it triples, driving snow into your face and sucking heat from you. You turn your back to the howling wind to form a plan. Shivering, you realize the storm is now a blizzard, and you must bivouac to survive the night. Removing your gloves, you feel your fingers become stiff and clumsy in the frigid wind. Opening your bag, you understand that seconds count. Given the wind’s speed, a tarp or emergency blanket will be difficult to hold onto, much less rig into a shelter. Only a mountaineering tent that can be pitched from the inside will stand up to the whipping, furious wind.

A lightweight alternative is a bivouac bag (bivy, bivvy or bivvi sack) or shelter, usually featuring a covered head space. It can be used by itself or to enclose a sleeping bag and pad to keep them out of the elements, which helps you to keep warm. Unlike an emergency blanket, a bag has no edges to let out heat and let in water.

Depending on temperature, humidity, elevation and time spent in a sleeping bag, people perspire and exhale moisture in different amounts. This moisture can condense inside a bivy sack so take this into account when buying a non-breathable bivouac bag. Condensation can be dangerous when using a down sleeping bag that loses its insulating properties and can clump when wet.

Less Is More

Some minimalists carry a lightweight (about 1-pound) military poncho liner or Kifaru’s Woobie or Woobie Express ( instead of a sleeping bag to use with a bivy sack for use in moderate temperatures. If you drill holes in your toothbrush handle to lighten it, consider the preceding combination of products in non-freezing weather.

If you’re used to sleeping in a tent, a bivy bag or shelter may feel confining or claustrophobic, so experiment before buying. Like most outdoors products, bivy sacks and shelters are available in numerous and diverse configurations. So, before buying, do sufficient research, including reading reviews, to discover all features, benefits, advantages and price points.

Author’s note: Be forewarned that bivouacking in stormy winter weather can be life threatening even when you have the appropriate gear.

More Bivy Resources

If you’re new to the world of bivy bags, visit  To view a comparison of bivy bags plus reviews, visit

**Note: The way you abbreviate “bivouac” will influence search results. Bivy, bivvy and bivvi are all used.

For More Information Contact:

Black Diamond 

Mountain Hardwear, (877) 927-5649

Mountain Safety Research

Outdoor Research

REI; (800) 426-4840

SnugPack; +44 (0)1535 654479

Survive Outdoors Longer; (800) 324-3517

This article originally published in THE NEW PIONEER® Winter 2015 issue. Print and Digital Subscriptions to THE NEW PIONEER magazine are available here.

Related Stories: 5 Off-Grid Survival Essentials

Up Next’s J5 Tactical Flashlight Is Just $11.95

The J5 Tactical Flashlight from features an adjustable focus zoom lens and an...