Sleeping Pad R-Value Explained
Much of the cold you feel at night comes from the ground, not the air. Your sleeping bag insulation is compressed underneath you, so the pad does most of the work of keeping heat in. The R-value tells you how well a pad resists that heat loss.
What R-value means
R-value measures thermal resistance: the higher the number, the better the pad insulates from cold ground. Since 2020, many manufacturers test pads with the ASTM F3340 standard, which made values from different brands far more comparable than older in-house figures.
R-values add up, so stacking a foam pad under an inflatable pad roughly combines their ratings.
Choosing for the season
Lower values are generally fine for warm summer nights, mid-range pads cover most three-season camping, and winter camping on snow or frozen ground calls for high values. People who sleep cold should aim higher than the general guidance.
A pad is also part of comfort: thickness and width matter if you sleep on your side or move a lot.
Care and backups
Inflatable pads can puncture, so carry the repair kit and avoid pitching on thorny ground. A thin closed-cell foam pad is a reliable backup and doubles as a seat at camp.
Inflating with a pump sack rather than your breath reduces moisture inside the pad, which helps insulated models last longer.