I've been reading up on vapor barriers and have decided to experiment with them on my short winter trips.
I've been mining the threads here for ideas for home made vapor barriers to experiment with and was hoping I could get some suggestions.
Ideas thus far are:
1) emergency mylar bivy as a vapor barrier... will probably work well but likely won't hold up for anything but the short term.
Perhaps there is some heavier source of mylar or some heavy duty mylar bivy?
I do use a mylar emergency blanket all the time for everything from an improvised mud room in the tent, sheet for spreading out my pack stuff, a layer between rainfly and tent in the snow... all sorts of things, and yet it's still inf fine shape if I need it for an emrgency. I've been using the same one for almost a year, funny how long it holds up. Still, it's a different story to sleep directly on it or in it since I'm one of those people who is always rolling over in the night.
P.S. I tend to lean toward a reflective layer but I've heard some say this is useless on a sleeping vapor barrier?
2) tyvek? seems a little stiff and perhaps even needlessly heavy as a vapor barrier. Though I think it'd make a great light weight outer shell / winter bivy since I wouldn't need my breathable gortex shell if I'm using an inner vapor barrier
3) nylon coated with spray on water proofer, i.e. a silicone waterproofer.
I'm thinking this would be the best option, it'd be tough and yet light and comfortable. My biggest issue is finding the right waterproofer. There are hundreds of waterproofers but I was hoping there might be some consensus on one that works best?
I.E. Kiwi Camp Dry
Granger's Tent Waterproofer
Nikwax tent waterproofer
4) some sort of ultrafine sheet, i.e. silk. The idea being I can have my vapor barrier and comfort too.
I'm planning on wearing very lightweight merino wool base layers to sleep in. So the shell need not be silken comfortable. indeed something a little plasticy and stiff might even allow me to slide in and out... or rollover inside the bag easier. It may even be a desireable quality. Not having experimented with anything yet I don't know.
As a broader question, what do you use as a vapor barrier? Home made or store bought I'm curious.