Hi, I'm currently using a PLUQ - it's gotten me down to 55 and I was warm, could probably go lower but haven't had the chance to try it any lower yet. Based on everything I've read, I would assume I could take it to mid-upper 40s by itself in no wind (wind really seemed to rob it of its insulating power). What I'm wanting to do is make something that I can attach onto what I have to be able to get me down to 20 degrees. My first thought was an Argon 90 shell for its weight and wind resistance, with a layer of Climashield for its stuffability. Some questions....

1.) 2.5oz, 5oz, or 6oz CS? What would get me down to 20 when paired with the PLUQ?

2.) Is a single layer of Argon ok? This would mean the CS would be up against the PLUQ. Or does the CS need to be completely enclosed in shell material?

3.) How wide should I make it? The PLUQ is ~40 inches wide, suspension line to suspension line. I know that I would need to make the add-on wider to account for the loft, but how wide? (probably depends on the answer to #1)

4.) I currently have a breathable SOL Escape Bivvy. Is it worth cutting it up to incorporate in the design (it should be able to make two 60" x 40" sheets)? Or just leave is as is and use in a pinch with top insulation?


Any help would be appreciated. Thanks in advance!