Loft isn't the only thing that matters for insulation...in a big air mattress, there is still circulation inside the mattress, which steals your heat. So you add insulation, like down or primaloft, to create small "microclimes" inside the insulator. Basically, each down cluster is its own little environment, and when your body heats it up the cluster will hold the heat rather than passing it along. That way your body doesn't have to keep the entire volume at the same temp.
So with a ziplock bag, any convective heat loss (from wind) will have a much larger effect than on an underquilt or pad.
Personally, I don't want to spend the time to fill up ziplock bags every night. I just throw up my hammock and get in. But that's just my style...you gotta find what works for you!
“Republics are created by the virtue, public spirit, and intelligence of the citizens. They fall when the wise are banished from the public councils because they dare to be honest, and the profligate are rewarded because they flatter the people, in order to betray them.” ~Judge Joseph Story
- My site: http://www.tothewoods.net/
- Designer, Jeff's Gear Hammock / Pack Cover
IMPOSSIBLE JUST TAKES LONGER