Originally Posted by permanentjaun
I'll see what I can do. I'm still waiting for my bivy to come in the mail. I'm also not bringing a stove on my trek. I might save a few ounces or a pound since I won't need the can stove or alcohol. Call me crazy, but I'm also not going to bring a sleeping bag. I bought a 'heavy duty' solar blanket with grommets in the corners. I figure at night I'll fasten two ends of the blanket together to make me into a giant egg roll. I tried it out last night and it kept me plenty warm. Since I'll be touring from May-July I don't have to worry about 0 degree temperatures. My thoughts are the the bivy will be a nice wind breaker. Then since the bivy is much smaller than a tent my body heat will warm the air inside easier than in a tent. That coupled with the solar blanket should keep my plenty warm and still have a feeling of being wrapped in a blanket to keep my comfy.
I got this blanket, which weighs .87 lbs.
http://www.actiongear.com/cgi-bin/ta...Fresults%2Etam
They also have a sleeping blanket solar blanket that weighs .18 lbs, but I don't think it'd be able to survive for extended periods of time on a tour. That's why I got the 'heavier' blanket. It's not much lighter than a quality lightweight sleeping bag, but this also cost me a nice $12.00. Can't beat that.
The main drawback of bivvys, and especially space blankets, is that they generally have poor ventilation. While this may be fine in cold weather, unless you are camping in arid conditions, they can be miserable in spring and summer. Even a bivvy by itself can be stifling on a warm humid night.
Bivvys are also very cramped and you can't bring much of any other gear into them. And space blankets are often pretty noisy with every little movement you make.
For little, if any, extra weight, you can use a silnylon tarp that will provide lots of airflow and room for the rest of your gear. Unless you are touring through treeless areas, you can use dead treelimbs off the ground for support poles. A simple inner tent made from bug net will protect you from insects.
If you're really hardcore, there are some extremely lightweight tarps available made from spinnaker cloth.
Another alternative is to use a backpacking hammock. This works best in wooded areas in temps above 65 degrees. A bonus with the hammock is you don't need a sleeping pad, so you save even more weight. However, if you plan to camp at parks, it's best to check their policies. Some parks do not permit hammocks to be fastened to trees.