summer bivy sleeping

you could try a few things. In a tent (I know different from the confines of a bivy) i've unzipped my bag and used it as a quilt. helps some.

next step is removing part of your body from being covered by the "quilt" or venting accordingly.

next step is to sleep on top of the bag.

if this becomes too cool you can add layers of clothing or tuck your feet in etc.

depending on bugs, humidity, wind, and precipitation you can apply some or all of the above on top of the bivy.

and as a precursor to any of that you can seek out a good site with a nice breeze

Ooops, sorry that's a 30 degree quilt, not a bag, sorry.

It's a matter of just seeing what works for you for a given set of conditions.

When it's warm enough I don't need any insulation with me inside the bivy, or sometimes extra clothes can be enough, or sleeping on top of the quilt or sleeping bag. Regardless of the insulation I use, I usually stay inside the bivy since I'm a light sleeper and can't sleep with bugs crawling on me.

Sorry to bring this up again….I just weighed my thermolite reactor and it comes in at a whopping 9 oz without the stuff sack! (9.7 with!).

Has anyone considered just sewing in a bug netting window into a mylar bivy?

I don't really reccomend sleeping in a mylar bivy. I tried that once. Then you'll really have a sweat factory.

It's just that I feel like I've hit a ceiling….9.0 liner plus a 6.5 oz bivy is almost a 30 quilt! Granted, u don't get bug or ground protection without, but doesent it seem like you should be able to sleep lighter in the summer? Maybe nothing in the bivy will be fine….hmmm…maybe ill drop the thermostat for a night to test….

Testing your setup in the backyard is a good idea as we move through Spring you should be able to test over various nighttime lows to get pretty dialed in on what you need at what temps. Your quilt seems a little warm for summer. I use a 40 degree quilt (Katabatic Gear Chisos) inside by Bivy (7oz KG Bristlecone) and I can use it for temps between 30-60 by varying my layers.