Sierra Designs Backcountry Bivy Review

Of all bivy sacks we have tested, few were quite as impressive as the Backcountry Bivy. For its weight, it outperformed every other model tested, scoring high in every metric. Not only is this a high performing lightweight bivy, but it is packed with extra features that we hadn't even thought to test, such as the stuff sack that cinches down its split long side, making stuffing a cinch, and an attachment point to lift the ceiling of the bivy off of your head, creating more space and comfort. A thoughtful design that was well executed and sold at a very fair price.

Performance Comparison

Weather Resistance

The weather resistance of the SD Backcountry Bivy is quite good. It lands somewhere between the highest performing Outdoor Research Helium and the all-arounder bivy sacks such as the Rab Alpine Bivi. We stayed dry in all conditions except for rain in extremely windy conditions. This was the only time wind blew rain into the non-waterproof zippers of the Sierra Designs bivy and water made it inside. It wasn't a large amount of water, but the wind subsided quickly. If you were in a prolonged and windy storm, the zippers would prove to be the weak point. If a windy/rainy climate describes your primary adventure climate, the Helium Bivy offered some of the highest weather resistance.

The bathtub floor design worked fantastically, keeping us dry from snow underneath; the rest of the body, while made of lighter nylon, proved to be just as water-tight. We also found the weather resistance to be enhanced when using p-cord to lift the roof of the bivy. This allowed water to run off quickly instead of collecting in pools, a common problem with most of the models we tested.

Weight

This thing is the Floyd Mayweather of bivy sacks — it weighs pretty much nothing and packs a big punch. One of the first things we noticed when unpacking this bivy was how light it felt in hand. We were excited to get it on the scale and surprised to see it register 387 grams or 0.85 lbs. If we exclude the emergency-style bivy sacks, the Sierra Designs is one of the lighter bags we have ever tested.

Keep in mind this weight includes a highly waterproof bivy, an entry/exit zipper and a bug screen vent w/zipper. Impressive.

Comfort

This contender found a way to be the jack of all trades. Not only did we feel protected from wind, rain, sleet, and snow, but we were comfortable while waiting out some gnarly weather. As you probably know, getting a good night's sleep can make or break your day. The whole purpose of bringing along the extra weight of a bivy is to be safer and more comfortable than just "going commando."

If the bivy is annoyingly loud, or cut in a way that you feel like you're wearing a straightjacket, you aren't going to get much sleep. The SOL Escape for instance, is cut much too small for individuals over six feet tall. Odds are those individuals, like our gear tester, will feel like they are slowly being digested inside the stomach of a giant python. Sierra Designs has made a bag that is comfortably sized, giving you plenty of height and width to remain comfortable but not have any dead space in the bag.

In addition to the generous space, they provided a tab to elevate the roof using p-cord and a fortunate tree branch. This extra space inside made a large difference when compared with similar models, such as the RAB Alpine. After having the headspace with no extra weight cost, we sure didn't want to go back.

Ventilation

Having used the Backcountry Bivy in several climates, we quickly discovered how well it vented excess heat, moisture, and stale air. We appreciate the multitude of different configurations possible with the Sierra Designs model, allowing you to dial in the right amount of ventilation. During warmer times the entire front half of the entry/exit opens and lays to the foot, providing maximum ventilation and the option to quickly button up the shell in case of inclement weather.

During a storm, you can unzip the screen for ventilation while remaining dry. While the protective lip wasn't as beefy or as stable as some, it did work well unless a big gust of wind hit it. As with all models we tested, if you didn't have something slightly unzipped for ventilation, the air would quickly grow humid.

Packed Size

We really can't say enough good things about this bivy sack. Other than the weight, the first thing we noticed was the clever storage sack and small size of the bivy. Only slightly larger than the ultralight emergency SOL Escape, the Sierra Designs was just as easy to stow. The Sierra Designs can be folded and rolled haphazardly and still fits into the stuff sack.

When it came to packing for an ultralight trip, we found we could store the Sierra Designs bivy anywhere in our Black Diamond Speed 22 bag. (our tester's go-to bag for ultralight endeavors). We even fit the bivy in the tiny brain of the Speed 22 with room to spare when we had made an early morning packing error. If you're looking for a lightweight, store-anywhere bivy option, you can't go wrong with this one.

Best Applications

We found the Backcountry Bivy to be an asset on every adventure we took it on. From bikepacking, multi-day ridge climbing, and backpacking, this sack pulls its weight. Yes, some models are lighter, such as the SOL Escape, another favorite of this year's lineup, but rest assured when there are storms in the forecast you will want the protection of the Sierra Designs over all of the other lightweight options. Sierra Designs has thought of everything, from the half body opening for warmer nights to the half moon bug screen.

We found ourselves stuffing the Backcountry Bivy into our pack most often when the weather forecast was unsure; those 20 percent chances of rain in the mountains when it could be sunny and perfect or a downpour. This bivy gave us the extra reassurance that no matter what, we would be sheltered. Times when the forecast was touting 100 percent gulley washers we opted for the burlier Outdoor Research Helium, as it could provide more complete protection.

Value

Separate from the rest of the competition, this bivy just performed well. We had no frustrations in any stage of use with this bag. It deploys and stores easily, it's warm and protected us from the weather and vented as well or better than the rest. For $140, it's the best bivy deal we know. Do know, though, that our favorite overall, the OR Helium, is just $40 more at full price, making the decision a bit tougher.

Conclusion

We thoroughly enjoyed using this bivy. We got the sense that this bag was designed by individuals who actually planned on using it and designed it to be both comfortable and to protect them from the elements. If you're looking for a well-designed, wallet-friendly, easy to use, lightweight, weather resistant bivy, look no further.