Designing a couple of Bivy sacks

cool everyone likes something different

my bivy will have taped seams even if i never use it in the rain :) guess ill never need to try them out

kevin

There are some great bivies now from small/cotage companies that fit 90%+ of the suggestions on this thread and are probably at the frontier of cost/weight/performance. It's hard to imagine how a major company is going to improve.

Sorry to rain on the parade, but sounds like this thread is reinventing the wheel.

The point of this discussion is not to "reinvent the wheel", but to find the qualities and features which will make a good bivy for UL users. It is unlikely that our company can compete with the cottage brands, however, we can learn from this thread and create a bivy which would help a more mainstream audience "go lighter". So far, I've found this thread to be most helpful;). Keep the thoughts flowing guys!

Thank you…

FR requirements are Federal and it is an issue for major retailers as well.

I like the idea, but the big question is how much did it weigh? I'd probably be all over this if it was in the 2 pound range. I would want the pad uninsulated and I would use a thin CCF as a groundsheet

Hi Austin,

Depends on what your looking to do. If your companies number one goal is to sell alot of bivy sacks then sure its probably a decent idea since no one else is doing it. To really jack up the sales even further you could probably sell them at Walmart with all the other Asian made products.

But if your number one goal is to make a UL bivy sack that works great then don't do an integrated pad. I would go with a floor material thats has either a PU coating or a thin laminate with a 5,000mm+ suter. Just make sure the floor is not a ripstop. Ripstop's are more prone to long term abrasion then plain weave materials and if you go with a ripstop then your floor is going to prematurely leak. As far as the top goes it needs to have atleast a 3,000mm+ suter so it can be used alone without a tarp or tent in all conditions. I am thinking a 2layer eVent to keep the weight down and since body oils wont be an issue you don't need the heavy third layer. The zippers need to be waterproof uretek and #5. Make sure all the seams are taped and the floor is a true bathtub. If you can do all this, get it under 10oz and make it in the USA I will buy one. Best of luck.

Any updates on this bivy?

I'm late to the show on this thread, but there is a lightweight simple bivy from every major maker. What I'd like to see is something like a black diamon or tnf backpackers bivy made out of lighter weight material and the use of poles or sticks to keep the top section up. I have the tnf bivy and use it quite a bit, but I detest the 1lb 13oz weight.

Think of something like a tt contrail (for size), split netting – half the height and width, rigid support for the head area and a 3/4 length side waterproof zipper.

Hey guys, glad to see some folks are still throwing in ideas! Without saying too much… I will say that I've narrowed down my concept, based largely on what I've read in this forum and on this site. I can say that cost, and a few other factors mean that what I want to do will not the the absolute lightest thing around. But…I'm hoping to be competitive on weight with the cottage offerings and have a unique design. It may be a while, but I'd be happy to share what I can, when I can. If anyone has any more thoughts, throw 'em down here! Thanks again everyone, I'm really excited about this project.

At the moment, I'm testing various fabrics, any favorites post 'em here. Looking at everything from Gore to Quantum. Focus is on breathability.

I don't know if you're still taking some ideas but between you and me, I'd love to see a good UL bivy that I could buy in a short size. Not a lot of options out there for short people. At 5'3" even the smallest bivy leaves me with a good 6" of head room which also forces me to go with a bigger tarp than needed and now I'm carrying no less than 5-6oz more weight than I even need, sometimes more! A shorter bivy would be awesome. Not smaller just cut of 5-6" I still like my elbow space. And I'd totally Beta test that!

I know for certain that Ron at MLD can custom make you a shorter UL bivy, as could several other folks.

I'd suggest looking at a WPB material for the bottom. I've seen a lot of evidence to suggest that elimating the waterproof non-breathable fabric on the bottom/bathtub goes a long ways towards reducing condensation. At least experiment with using something other than sil-nylon/cuben fiber and see what you think. You could also use the WPB material to wrap up and around the feet for a full WPB footbox area. It'd come in a little heavier from other offerings, but it'd be a huge distinguishing feature and would be more attractive to those that use their bivies for more than just clear-sky summer weather.

Any links to that information? I'd love to read it.

I am in a testing phase now and the product will debut at the August Outdoor Retailer show. Initial response has been good and early testing was positive. I would like to thank everyone for the comments and BPL for the informative articles.