Uncommon Challenge: Sleep (Well) In a Bivy Sack

Our test dummy trades in his tent for an emergency shelter in a non-emergency.

I’ve been prostrate on the ground now for more than an hour. Outside my nylon fortress, the rain is relentless, coming down cold and steady, pelting my bivy.

Inside, it’s cozy and comfortable, and I’m warm in my sleeping bag. But, with only enough room to lie flat and the top of my shelter no more than a foot from my face, I’m not exactly having fun or getting the expansive dose of wilderness that I’d hoped for on my solo trip into the Rockies.

You see, it’s 5pm, an awkward time for sleep. In any other circumstances, I might wait out this biblical rain by playing solitaire, entering a note in my diary or even cooking a fine freeze-dried dinner in my vestibule. But those require elbowroom, headroom and oxygen flow⁠—things I don’t have. Instead, I’m lying on the ground, willing myself to fall asleep before the sun has even set.

It’s a bit of a bummer⁠—a worst-case scenario for the ultralight adventurer. When backpacking with a tent, inclement weather is easy to manage. There are giant vestibules for storing gear and much living space for hanging out and sipping whiskey in comfort. You huddle inside and enjoy life’s present offering, running out to feed the fire and catching yourself staring at the electric currents streaking across the sky. There’s a romance to it.

Today isn’t so magical.

A bivy—short for “bivouac sack”—is as simple as a shelter gets. It’s essentially a rain jacket for your sleeping bag, sleeping pad and you. With packed weights of a pound or so, these scant shelters are great insurance policies against a bad (or unplanned) night out. They’re lighter than tents and require less space inside a backpack. Nothing is better for moving fast and light through the mountains.

Say a solo traveler sought to bag a remote peak or two in a remote range. If that person intended to either (a) return to the trailhead before dark or (b) knock off mid-mountain for a few hours before returning to the trailhead, he or she might opt for a bivy. But a bivy would be a silly choice for someone who was lackadaisically walking through the mountains when the skies opened.

Earlier in the morning, I had set off beneath a shining sun with the intention of enjoying some stress-free alone time in the woods. I’m not a stranger to hiking solo, but I am to bivouac sacks.

In the vacant space where I might have carried tent poles or a footprint, I packed a hardback, a journal and a beer. (A true bivy user would probably fill the empty space with air and gloat about it at the trailhead.) When I reached a meadow I know about, my own backcountry Shangri-la, I tossed my pack to the ground and got started on sorting out life’s greatest riddles.

Soon enough, the clouds came rolling in. I tried to take shelter under a tree. I was impatient, though, and the cover of the spruce ultimately proved ineffective. I had no choice but to retreat inside my bivy. I wrapped my backpack in its cover and stashed it under some thick brush (there’s no room for a pack inside a bivy), then shimmied into my nylon sack. I stood there in it for a while, leaning up against the tree.

But the rain showed no signs of stopping, and fatigue forced me down to the ground, where I currently lie.

I’m tucked inside the four-season, Outdoor Research Interstellar Bivy, the Cadillac of such shelters. Like the brand’s premier ski jackets, it’s made of impenetrable, three-layer AscentShell that’s decently breathable. It’s fully seam-taped, and a 40-denier ripstop base and polyurethane floor mean you can throw it on practically any surface without fear of tears or leaks.

The Interstellar Bivy has six sets of two-way zippers. At first use, it seems like a mess. But once I sort them out and arrange my body parts accordingly—one for each arm, one for my head, one for the bug screen, a couple for the rain cover—it begins to make sense. With the one (optional) cross pole, I can prop up the zone around my head to create a tiny globe. If I do this, then unzip the mesh away from my face and unzip two holes for my arms, I can “wear” the bivy (Outdoor Research calls this “sombrero mode”).

Rain, however, ruins this experience. I have the hood completely zipped up, save for a small gap in the side, near the ground. Through it, I can see rain drops hitting the dirt, which remind me that I am not inside a coffin. Every so often, a big one hits the ground and splashes my face.

I feel claustrophobic. It’s quite dark inside. I try to read by the light of my headlamp to pass the time, but my arms get tired holding up my book. So I stare at the mesh above my head until it blends in with the ceiling, and I wonder where one gives way to the other. I contemplate my decision to forgo a tent.

At some point, I realize I’m hungry. I reconfigure the zippers to “sombrero mode” and hop like I’m in a potato sack over to my pack and retrieve my cooking pot and stove. I sit with my back against the tree, looking out over the meadow. The clouds are hanging low and grey; the rain is falling on the tall grass. I can feel the water dripping down from the tree’s highest boughs and landing on the hood of the bivy. I eat my soup and lie back down on the ground in the rain.

The concept of the bivouac sack is great in theory—super lightweight, super easy, super stargazing. It’s keeping me warm and dry in the rain, and I can indeed cook while wearing it. For the minimalist wanting to maximize, it’s solid.

But, bivy user beware: There’s risk in leaving your tent behind. Small shelters have drawbacks, especially in bad weather that comes before bedtime.

Uncommon Challenge is a column where we challenge each other to make unusual gear additions, subtractions and swaps. All challenges (and subsequent bouts of suffering) are voluntary and not recommended unless explicitly stated. Have an idea for a new Uncommon Challenge? Leave us a note in the comments.