Bivvy vs. Sleeping bag

[Truehart]

I've never used a bivvy before. Other than being considerably more compact, how do they compare to sleeping bags/quilts? I.E. Is there a learning curve to using a bivvy?; Can they be used in a hammock the same as they are used on the ground?; etc.

[DanglingModifier]

I've always considered a bivy to be basically a condom for my sleeping bag. It provides windproof/waterproof shelter, like a tent or tarp. It isn't designed to substitute for insulating bedding material. A bivy is hard to beat for low weight, ease of setup, and fitting in tight spots a tent can't. In return they can be really claustrophobic, hot and prone to condensation issues. Not much of a learning curve using one. Setting one up and getting into it is pretty similar to laying out and squirming into a zipped up sleeping bag, or putting on a sock the size of your whole body.

You wouldn't want to use one in a hammock. If you were crazy you might want to use one instead of a hammock. If so, I'd be happy to sell you a nice 4-season bivy that's essentially brand new.

[Truehart]

Thanks, DanglingModifier. That was my basic understanding of them, but another thread got me thinking about the SOL Escape Bivvy. The price and size are right and it's supposedly breathable, but I'm just not sure I'm ready to give up my current bedding (sleeping bag).

[OutandBack]

I would not trust everything you read on the internet even here on HF.
YMMV

[pgibson]

I would not trust everything you read on the internet even here on HF.
YMMV

On this topic +1

A bivy is not insulation, it's a shelter. Breathable is a relative term. Nearly every bivy made will state that it's made from Breathable materials.

[Scotty Von Porkchop]

Dangling modifier is spot on, a bivi is definitely not a sleeping bag or quilt replacement, more a tent/tarp replacement.

The SOL bag IMHO is garbage.

[BillyBob58]

Thanks, DanglingModifier. That was my basic understanding of them, but another thread got me thinking about the SOL Escape Bivvy. The price and size are right and it's supposedly breathable, but I'm just not sure I'm ready to give up my current bedding (sleeping bag).

I know the thread you refer to. Says he got as good or better insulation(if I understood him correctly) with that SOL inside his hammock, than with his quilts or pads, or at least it was pretty warm and real comfy. Kind of hard to believe but maybe he will chime in here.

Now, shelter from the wind and rain makes perfect sense, though condensation can sometimes overcome those benefits.

[OutandBack]

So many do not understand the whole radiant heat thingy.
When radiant heat is less than 10% of how you stay warm and an item boasting it will reflect 90% of your radiant heat.
Well 90% of less than 10% is pretty bad.
I would make a top quilt and underquilt from a cheap fleece throw, some slingshot rubber and 550 cord before trying reflective foil.