To increase the warmth of a NeoAir, taking it down to maybe 20-25 F, what thickness of GG Thinlite works, the 1/8"? Or do you need 1/4"? At those temps, I'd likely be using a Helium bag. I'd like to not have to carry my BAIAC pad instead if I can help it.

Gary,

If the ground is at 20 - 25F, then you need the R-Value under you to total at minimum ~3.8. The Neoair's R-Value is 2.5. You need a supplementary pad of R-Value ~1.3. Any 3/8" CCF pad will provide R-Value ~1.3 to yield the total you require.

Some people will report that they were fine with less of an R-Value supplemental pad. The ground temp is frequently warmer than the air temp but not always. In addition there are other factors that can reduce the need for bottom insulation.

Edited by richard295 on 10/25/2009 09:57:36 MDT.

Thanks, Richard. Your opinion/knowledge is always most valuable. Looks like I was dreaming about the 1/8" Thinlight working for this. I'm putting in an order for some GG stuff today, and your response is timely. Thanks again.

I used a ThinLight 1/4" cut to torso length in VA earlier this month. Night temps got down to 30-32* three nights in a row.I stayed very warm with this combo under me. On top I was using the JRB Stealth quilt rated 45* and Montbell UL down jacket and pants.

Working off of Richard's reply, is there a chart giving a suggested R value for a given temperature?