>>472575>How did you get water condensation?>No water penetration what so ever. I have no idea what you need to do to get water pass into a membrane like GoreTex when you're inside. You don't understand what condensation is, nor how it works in a bivy bag in cold weather.
I was about to type up a post explaining this to you, but
>>472594 already did.
>>472605>breathable membranesIf you only ever spend a few nights out a year, then maybe you just don't have enough experience to know, or maybe you simply have never been in the "wrong conditions" for condensation to form, but Gore-tex is not cotton. Yeah, it's breathable, and it allows water vapor to pass through, but water vapor doesn't move nearly as freely as it would need to in order to prevent condensation in these conditions.
Nor, actually, is the bivy the only problem. In cold enough weather, moisture from your sweat and breathing can reach dew point WITHIN your sleeping bag insulation itself. Usually, it will reach dew point somewhere outside of your sleeping bag, though, condensing as liquid water on either your sleeping bag's shell fabric, or the inside of the bivy. Under normal circumstances, this would evaporate, and be transported to the outside air. In cold weather, it can freeze, or else it can simply get wet enough to overpower the evaporative process.
Maybe you're the one who needs to do his homework on what waterproof-breathable membranes are and what they do. Gore-tex will not transport liquid water, nor will it transport ice. In cold enough weather, that condensation can actually freeze on the inside (and also on the outside, in the right conditions) of the bivy fabric, thus turning it into a vapor barrier. Liquid water does much the same thing, as long as it is not in a vapor state.
>it never happened to me>therefore it can never happen everWhen multiple people are saying independently that condensation is a problem, it might be time to consider the possibility.
