Compare the 64 Bivy Bags on Ten Pound Backpack based on their weight, price and a few more features as well.
One of the many reasons that people choose a bivy sack over a tent is that a bivy sack weighs quite a bit less and takes up quite a bit less room. But there are certainly some big, heavy bivy sacks out there that will rival the weight of smaller tents, and so it helps to look for a lightweight bivy sack, and not just assume that your bivy sack is going to be lightweight. That way, you get all the advantages of using a bivy sack, without sacrificing weight.
Lightweight Bivy Sack
What you want to pay attention to when you want a lightweight bivy sack.
Supported – Many bivy sacks come with poles that make the bivy sack in to a very small tent, which certainly does have a few benefits, such as increasing air flow. But all that extra material, not to mention the poles, adds to the weight of the bivy sack, and if you want a lightweight bivy sack it’s best to avoid those structured bivy sacks.
Material – The material that your bivy sack is made out of will also help determine just how lightweight it is. Something like Gore Tex is a good fabric for a bivy, because it breathes but is also waterproof, but Gore Tex is also heavy. So pay attention to the fabric that bivy sacks are made out of if you want a lightweight bivy.
Best Lightweight Bivy Sack
Some of the very best lightweight bivy sacks to take on your next backpacking or camping trip.
Rab Alpine Lite Bivi - The Alpine Lite Bivi is exactly the kind of gear you want when taking a bivi sack in to alpine conditions, as the name suggests. The top of the bivy is very breathable eVent fabric, which is waterproof, similar to Gore Tex, but the main thing being that it is very breathable, to allow moisture to escape. That is complimented by a completely waterproof bathtub floor, and a U-shaped opening along the top edge of the bivy, so that there is no face opening for rain or snow to pelt you in the face through. And all for a weight of just 15 ounces, or 420 grams.
MSR E-Bivy - The top of the E-Bivy is a silicon coated nylon, while the bottom is a heavier duty. So while it would be generous to call the E-Bivy waterproof, it will do a decent job of keeping you dry in light moisture, and being nylon, will breath very well, so at least you wont get wet from the inside. It has an overlapping face opening, so that you can be protected from the elements while still getting lots of air circulation. And at just 9 ounces, or 255 grams it's light enough that you'll hardly even know you're carrying it. So maybe not waterproof, but an ideal bivy sack for good weather.
Terra Nova Ultra Bivi - At just 2 ounces, or 50 grams, the Ultra is the lightest bivy sack on the market. It's even waterproof, but unfortunately not breathable, so if you're not careful you will end up getting wet from your own generated condensation. It also has a fully exposed face opening, so if it starts raining or snowing there is at least one part of you that is going to be getting wet. Still, you cant beat the weight of the Ultra. The price, however, is also extreme, so if you're not looking to spend a lot, this might not be the lightweight bivy sack for you.
Find plenty more bivy sacks that you can rank by their weight over at the compare bivy sacks page.