i have been trying to dial in my gear for an upcoming trip and have alittle frustration.i slept out in the yard (again) last night in my Marmot Alpinist bivy with my pad inside my sleeping bag to keep in place.i was on the ground but in my Golite SL-3 left a few inches off for ventilation.i slept with the bivy open above my shoulders and had a great sleep but woke up to some serious condensation under my bag.any thoughts as the bottom i presume is non breathable while the top is.is it a bad practice to place pad in bag which keeps the sleeping bag tight to bottom or after reading a pile of threads about bivy condensation is this just par for the course?i should add that it went down to 5 celsius (40sh F)and the inside of the SL-3 was soaked also.any thoughts as i am still a bivy newbie would be greatly appreciated -thx
p.s -thoughts on the SL-3 would be good also but it will problaby not go as i would prefer to just bivy and use poncho if needed to cook/read etc

you shouldnt need a bivy inside a sl3 unless its a ragging storm outside and yr tent gets blown away

yes i am aware of that but i was testing the bivy and hiding from the neighbours :) - i did say i will be taking poncho for bad weather

I just bought a Alpinist but from what I've heard it's just the trade off for a bivy was the humidity high ? But for the convenience of a
Bivy I will deal with some condensation

Quite surprised that you had condensation given you were in the SL3. It tells me that the fabric used is not in the least breathable. If you must have a WP fabric, look toward eVent. Otherwise, a non-wp fabric is the way to go. (IMHO)

First I was surprised that you had the pad inside your sleeping bag. Put it under the bag and inside the bivy and your bag will be up off the floor some. I have done a ton of research on bivies and used a fair number and like David said the WPB fabrics, other than eVent and Gore windstopper, are generally not breathable enough. Even eVent with a silnylon floor has problems from time to time.

You must have been in a really humid situation if the inside of the tent was dripping too. Bivies have the most trouble down in those temps just above freezing when the dew point is also very low. You can also try to suspend the top of the bivy with a bungee cord so that there is better air flow over the top of the sleeping bag.

Edited by abhitt on 04/14/2011 14:30:34 MDT.

As the last person said, your bivy should go under your sleeping bag, not inside. You might get less condensation if you place it outside your bivy.

thx guys -i will have to give it another go.it is still rather damp here and the snow has only been gone for a week or two.i will try with the pad under the bivy also although it will be more difficult as it is a tiny/narrow pad and a pretty big bivy

Anyone had any experience with the MLD superlight bivy? Any problems with condensation? I just got one from gear swap and am really excited to get out and test it out!