Temperature affect

**Old Man** · 01-29-2013, 07:23

How will stacking quilts affect the temperature rating? A 0* and a 20* UQ stacked would have an approximate rating of?

**Bubba** · 01-29-2013, 08:50

Can't give you an exact number. The 20* will certainly add a lot to the 0*. if the two are stacked in such a way that both of their lofts are not compressed in any way it should be toasty.

**breyman** · 01-29-2013, 08:57

Originally Posted by Bubba

Can't give you an exact number. The 20* will certainly add a lot to the 0*. if the two are stacked in such a way that both of their lofts are not compressed in any way it should be toasty.

Agreed. I would think it'd bring you down to at least -15 or 20. As a note, LeighLo has a pretty good video on stacking underquilts. Check out this page, half way down, under Stacking UQs for Deep Winter:
http://www.hammockquilts.com/apps/videos/

**hangnout** · 01-29-2013, 11:52

Originally Posted by Old Man

How will stacking quilts affect the temperature rating? A 0* and a 20* UQ stacked would have an approximate rating of?

This thread from WhiteBlaze gives a formula that Pan from JRB provided.

Quote from thread linked above

x - ((70 - y)/2) = z

x = first bag (higher rated/lower degree)
y = second bag (lower rated/higher degree)
z = rating of doubled bags

Extra set of parenthesis to make it crystal clear that the x is not divided by 2, just the 70-y part. I think you're correct about the order of operations implying that anyway, but the parenthesis makes it clearer for anyone who hasn't had math in a while!