Thanks lymphocytosis. I'll check him out.
Thanks lymphocytosis. I'll check him out.
I've got an older version of the Adventure Medical thermolite bivy. I've been kicking around giving it a try in this fashion. I just figure it will be be a real pain to try and wriggle into the bivy then get under my quilt (better than trying to get into another bag).
When you got up in the morning did your body heat dry out your thermals pretty quickly or did you stay clammy for quite a while??
olzeke;586593]The only time I tried sleeping in my rain gear, I woke up cold and wet. I found the barrier to be too efficient and it trapped my sweat next to me. No thank you.
1st time I use a VBL I put it on the outside of my sleeping bag. I figured it would keep the heat in and dew off my bag. Needless to say, it was disastrous & glad it was tested in a shake down hike.
2nd time was almost as bad. No clothes, and my body quit putting out heat, with wind blowing on me. Woke up freezing.
I went with thin nylon socks, silk long johns and I found a good combination for many cold nights.
I also added a JRB protector over my bag. I found for me, I didn't have to worry about getting my gear wet.
Normally, any moisture passes through the down quilt of sleeping bag, and is passed off to the air. We do not notice any accumulation of moisture in the down unless we are out for long trips in cold weather. Seems it takes more than 10 days for it to be noticeable.
My concern is on night 2 of a 10 day hike, the fog rolls in. I've woken up in a wet mess. However, most who venture out on a cold 10 day hike have a bail out, back up plan in place. Also, I think most long distant hikers come to accept they're going to be cold & uncomfortable to a certain degree. I think VBL is something every hiker needs to have some knowledge about & use it as a tool for survival & not comfort
Also, back then I was using HH (Enter from the bottom) a large air mattress (2 lbs), a 20 degree North Face Mummy bag & VBL bag. Needless to say, I'm sure if someone saw me trying to get on the air matt, and get into both of the bags, it looked & sounded like there was an orgy going on inside. It did take time, and it was a PITA, but it wasn't like I had anything else going on at the time anyway.
VBL clothing does away with all of the hassle of trying to get a liner bag inside another bag, and is also useful while sitting around camp. Other than using a VBL/space blanket in my HHSS and sometimes PeaPod to extend the temp range and keep things dryer, the only VB I have ever tested are socks. But sometimes it is amazing what the combination of completely stopping evaporative cooling PLUS keeping your insulation dryer can do. I still remember well the day in northern AZ fishing, and my friends feet were freezing, and he was miserable. I had some Patagonia VB socks which I had not even used. I loaned them to him. He put them under his socks inside his boots. Bingo. It was not long before his feet were just fine.
Wisenber has had some amazing results using VBs.
Apparently, signature that I used from 2006 no longer tolerated so now deleted.
Excellent thread! Great info!
Question... Are UA or silk under garments considered VB? I think I have some somewhere and I should find them before friday!
Thanx in advance...
So I've always been intrigued by VBL's, but don't own one and never tried one so all I've got is book learnin' and no real world experience, and I stand to be corrected ...
It's my understanding that one of the most important considerations when using a VBL, is that even if you like to sleep toasty warm, you need to actively regulate your system so that you sleep cool.
The VBL is designed to regulate the small amount of moisture your body passively gives off, by creating a microclimate such that the water content in the airspace between the VBL and your body, equals the moisture level your body is giving off. When this balance is reached, your body quits shedding this moisture, (picture osmosis) and you sleep in a comfortable environment.
If you start getting warm and fail to recognize this and shed some layers of insulation in time, your body actively tries to cool itself by sweating. If you start to sweat in your VBL, you mess up this balance and you end up wet and shivering.
The traditional advice of eating hearty and warm up with exercise before retiring for the night is contraindicated for VBL use.
Starting the night with a dry non-cotton sleepset and sleeping cool seems to be the key to success with VBL's.
In the morning, when I get out of the bag, I slip right into my boots and quickly march around camp in just my smartwool longjohn tops and bottoms, and they evaporate really quickly. This gets chilly. When I'm cold enough that it's time to pull on my pants and jacket -- just a couple minutes -- the top and bottom are dry enough that they easily keep evaporating inside my pants and jacket, and with the jacket zipped open a bit I don't think much ends up getting stuck in my down jacket's down. It would probably be more efficient to sleep naked inside the VPL, jump out of the sleeping bag and quickly into clothes that had been kept inside the mummy bag, and thus warmed up. I will try that next time.
I am AMAZED at how toasty warm you feel when inside the humid environment of the VBL. The perception is so much warmer than just being in the bag without the VBL. Very toasty.