So 3 days ago I had my first child and I am lucky enough to have 2 weeks of paternity time to spend with her. But she sleeps a lot and I find myself with some free time.

What should I do... I know. Let's make something!

I'm looking at slimming down my sleep bag from 29oz to something less without spending much money. Here's my idea:

Use a AMK emergency bivy as the bag itself and include 2 yards of 5oz Primaloft One (60" wide) on the inside. The insulation would be held in place by No-see-um netting. The netting and the bivy would essentially create a pocket for the insulation to be put into. There would be no insulation on the bottom of the bag and would make it essentially a quilt.

So in theory does it work? I wanted to use something more for Fastpacking other than my standard sleeping bag. Yes I am aware of the vapor effect but I was hoping the synthetic insulation would be able to dry fast enough if I were to get it really damp. I would be using this setup with a poncho tarp so I would get the added bonus of having a waterproof bivy for protection.

Bivy = 3.8oz
Insulation = 10oz
Netting = ???

I have no idea how to construct it but I reckon I have at least a week to find out. Like always I am looking for feedback good or bad!

I'm not sure how long you plan to use it but the AMK bivy will eventually develop pinholes and worn areas (especially being stuffed into a stuff sack repeatedly). It also does not sew well and will be perforated unless you use seam tape or is bonded instead.

Yeah I knew sewing would be out of the question using that type of material but I figured I could use some sort of bonding glue/tape.

I wouldn't use it as my "do all" bag but only when I plan to do some big mile/little sleep hikes. I wouldn't stuff but rather fold and roll.

Forgot to mention I would be using this more in the summer and in the PNW.

You might be able to attach the Primaloft to the bivy with some kind of spray adhesive, a la 3M Super 77 (http://www.amazon.com/gp/product/B001CGRPPE), and then the netting to the bivy with tape along the perimeter and a few choice stitches to keep it in place. This would minimize the number of holes in the bivy.

That being said, I agree that its durability would be questionable and it wouldn't be that comfortable to sleep in due to lack of breathability. If you have some Primaloft laying around it would make an interesting project, but I would consider it a pretty minimalist item.

Andrew