Waterproof/Breathable Outer Layer?

[^shane^]

I still don't have a hammock yet, but am already beginning to plan for quilts, both over and under.

I have two Sierra Designs down bags that have their "Drizone" waterproof/breathable shell. These are wonderful bags and the waterproof shell is the real deal. Their shell material got me to thinking...

Would an outer shell similar to Drizone (or any other waterproof/breathable) fabric laminate work for an underquilt? Would this cause trouble with condensation? I do not experience condensation problems inside the sleeping bags when in use.

My thought is that this shell would protect the underquilt from getting wet from splash or wind-driven rain. I understand there might be a miniscule weight disadvantage, but seems worth it compared to carrying another "under cover" of some kind.

[BillyBob58]

Well, I guess that would depend on just how breathable the material is. Most seem to feel that any of the WPB fabrics will end up causing some loss of loft from condensed moisture. Then again, JRB offers the Driducks poncho conversion meant to be used as an UC and that is WPB. I haven't read any comments yet about how well that works.

[lori]

Driducks is breathable and waterproof. "microporous polypropolene."

I think most underquilts are DWR outside and plain ol ripstop inside, to facilitate moisture transfer. Adding the Driducks as an undercover is of more interest to me than having a waterproof quilt; I want to be able to throw the quilt out to dry. I also like having the poncho with me to shed rain and/or the occasional waterfall spray from the pack.