Heat of adsorption, damp weather, breathing inside the bag: why wool works when the air is wet.
Most cold nights are really damp nights. This is the science of why wool handles them.
Wool takes water vapor into the fiber and gives off heat as it does — the heat of adsorption — which is why a wool bag still feels warm when the air is wet and a synthetic one feels clammy. These articles explain why damp weather feels colder, how sleeping bag temperature ratings are tested and what they leave out, and the honest trade-offs in wool vs down sleeping bags: weight, loft, wet performance and cost.
If you are weighing a wool bag for backpacking, read how much a wool sleeping bag weighs first — we give the real numbers, including where wool is heavier.
How much does a wool sleeping bag weigh? Ours run from 4 lb to 15 lb depending on the bag, the size and the loft. The one you would carry — the Rewilder in Standard 2″ loft, field rated 20°F — is 4 lb / 1.8 kg, which is about three times the weight of
How Much Does a Wool Sleeping Bag Weigh? (And Why It’s Worth It) Read More »
Summer Nights Call for a Lighter Sleep System There’s something special about sleeping outside on a warm summer evening. The air is soft, the stars stay out late, and you don’t need bulky winter gear to enjoy a comfortable night’s sleep. One of the greatest advantages of wool is that it naturally regulates body temperature.
Why Wool is Perfect for Summer Camping Read More »
[New] Weatherwool Sleeping Bag We are rolling out the next evolution in sustainable sleeping bag design. This is the same trusted design as the Rewilder with a powerful new material. We’ve upgraded our signature sleeping bag with a Weatherwool liner for next-level comfort and performance. Enjoy stronger wicking, faster breathability, greater durability, and the same ultralight feel as before —
Trailblazer Sleeping Bag Demo Read More »
Does wool keep you warm when wet? In my experience, yes—and the reason has a name: the heat of adsorption. Two questions land in my inbox every week: does wool absorb water, and is wool absorbent at all if rain beads up on a wool coat? The answer to both is that wool takes water
How Wool Stays Warm When Wet: Heat of Adsorption Explained Read More »
Ask me why wool is better than synthetic or down for sleeping and I could give you the textbook answer—warm when wet—but that is the least of it. In my experience wool is the only common insulating fiber that works with the moisture your body makes every night instead of trapping it against you, and
Why Wool Is Better Than Synthetic and Down for Sleep Read More »
Why does damp weather feel colder? Forty degrees and raining will chill you faster than twenty degrees and clear—anyone who has spent a November night in the Southern Appalachians knows it in their bones. The plain answer is that damp air and damp clothing take more of your body’s heat to warm than dry air
Why Damp Weather Feels Colder (and Why Wool Still Insulates Wet) Read More »
Down bags are light and pack really small. I have said that in print and I will say it again here: a 20°F down quilt weighs one to two pounds, and my Rewilder wool sleeping bag weighs four. If weight were the whole wool vs down sleeping bag question, this would be a very short
Wool vs Down Sleeping Bags: Weight, Wet, Loft and Cost Read More »
A “20°F” bag is not a promise that you will be comfortable at 20°F. Depending on who printed it, that number may be a lab figure for a standard woman lying relaxed, a lab figure for a standard man curled up and coping, or a number the maker picked. This is sleeping bag temperature ratings
Sleeping Bag Temperature Ratings Explained (ISO 23537 and Wool) Read More »
