Showerthought: the R-value on my sleeping pad dropped 2 points when I tested it on real dirt vs concrete

I was reading through some gear tests on a backpacking forum and found a guy who tested sleeping pad R-values on actual ground instead of a lab floor. Turns out my Therm-a-Rest pad loses almost 2 full points of insulation when it's on dirt and leaves compared to their fancy testing surface. That means my "winter rated" pad is really only good for spring temps when I'm actually camping. Has anyone else bothered to test their gear in real conditions or am I overthinking this?

2 comments

2 Comments

sageallen3d ago

My buddy Dave tried this last winter with his Nemo pad on frozen ground and woke up shivering halfway through the night. He said the cold just seeped right through compared to his driveway test. You ever have that happen where you think you're prepared but the ground says otherwise?

victorbutler2d ago

Man I had a buddy Mike who tried the EXACT same thing with a fancy insulated pad on his back deck in January. He did a full test run, felt fine, packed it up confident. Then he took it to a gravel bar by the river two nights later and woke up with his hip bones feeling like ice cubes. Said the difference between test conditions and real ground is like comparing a warm garage to a walk-in freezer. There's just something about that raw earth that pulls the heat right out of you no matter how good your gear is.