TIL that sleeping pad R-values are total BS after comparing three top rated models last weekend

I was at REI reading the box on a Therm-a-Rest and noticed the R-value listed was 4.2, but then I saw an REI Co-op pad with the exact same R-value for half the price. So I bought both plus a generic Amazon one, took them out to 38 degree weather in Big Bear, and the cheap pad was actually warmer than the expensive Therm-a-Rest. Has anyone else tested this or am I just getting unlucky with specific pads?

3 comments

3 Comments

hall.joel8d ago

And honestly that kind of lines up with what I've heard from a few guys who work in outdoor gear testing, they say the whole R-value standard is more of a suggestion than a hard rule. The test setup they use in a lab is just a flat surface with no wind or ground moisture, which is nothing like actually sleeping on dirt in a tent. So idk, maybe people should just buy the cheaper pads and test them in their own backyard instead of trusting the numbers on the box.

emerym367d ago

Yeah, that "flat surface with no wind or ground moisture" part really got me. I tried one of those high R-value pads on a cold night in a damp meadow last spring and it was like the ground was just sucking the warmth right out of me anyway. The numbers on the box felt like a cruel joke. How hard would it be for them to test these things in actual dirt with a little wind?

torres.thea6d ago

@emerym36 that "flat surface with no wind or ground moisture" thing is the real killer. Actually the standard R-value test uses a cold plate and a warm plate with the pad sandwiched in between, no air moving at all. So that damp meadow floor with a little breeze basically turned your pad into a different product entirely, because real ground has moisture and airflow that the lab just ignores.