Quote Originally Posted by MacEntyre View Post
That's a good approach, I'm sure. On cold hangs last winter I used highly breathable fabrics, for the same reason: to keep condensation out of the down. I was amazed at how well it worked. So, I've become an insulation schizophrenic, alternately using non-breathable and breathable layers. What got my attention was the realization that there is a huge humidity differential between my skin at 85*F and the outside at -15*F. I think some of us don't make much condensation, or it goes up or out or somewhere, while others find a puddle of water in the morning.

- MacEntyre, up at 0430, tough to stay on-topic
Quote Originally Posted by JerryW View Post
I think that is the key statement right there! Some folks can get away with using a non-breathable inner layer and others can't. Individual experimentation needed.

Everyone is different, just like being a cold or warm sleeper.

Maybe this is the reason for the big variability of folks experience with the HHSS with space blanket?