The REI Co-op Joule 21 is a high scorer, providing ample warmth wrapped in a lightweight design. It is heavier than the Neutrino but also warmer and much less expensive. It kept us warm and cozy on cold, wet, and windy nights in the High Sierra, and its 700 fill-power down insulation provides a good night's sleep in the backcountry. We also appreciated its low weight-to-warmth ratio, and think the Joule is an excellent choice for any backpacking need at a great price.
REI Co-op Joule 21 Review
Cons: Uncomfortable fit, zipper fabric bulky and uncomfortable
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Our Analysis and Test Results
A high-quality bag that's warm and relatively light, the Joule is a pleasant surprise to our testers.
The Joule is one of the warmest sleeping bags, beating out competitors rated at 15 degrees. We feel that its EN rating of 21°F is dead on, and indeed, it kept us warm down to that temperature. The bag feels cozy, and the 700 fill down is very lofty. The Joule's shell material protected our testers from the wind when they slept out under the stars on windy nights.
The bag's shell material has a waterproof coating. This detail was added peace of mind when we were in a torrential downpour in a floorless shelter. It kept us dry throughout the night despite a constant misting from water bouncing off of the ground and tarp. This bag could be a good option for someone who wants a down bag in a wet climate like the North Cascades.
The Joule 21 weighs in at 2.19 pounds, which is not super lightweight for a down sleeping bag but still suffices for any backpacking trip. As the years go by, more and more competitors are surpassing this product in this category, and it is easy to get a sub-two pound product for about the same price.
Thankfully, REI has abandoned the woman's hour-glass shape and made the leg area larger. This change is an upgrade. The proportions were previously about as exaggerated as Barbie's. Now the bag is much more comfortable, and the dimensions are much more comfortable for sleep.
The stuff sack included with the Joule is not a compression sack but is made from lightweight materials. When we took it out in the backcountry, we used one of our own compression sacks instead, and it packs down quite small. This arrangement makes it a great choice for backpacking.
REI has trimmed the fat in this department, and we are in favor of the work they have done. They have gotten rid of the stash pocket entirely and added a light colored liner fabric so you can find your missing sock without difficulty. The color hides dirt. The zipper works well, contrary to reports we read about this bag and so we are wondering what's with the super burly zipper lining fabric? We think it may be a reaction to complaints of zippers catching on this bag, but unfortunately, it adds weight and bulk, and our testers can feel it when they're sleeping; it bunches and creates a hard, uncomfortable lump.
Although the waterproof coating on this bag works well, it also adds extra weight. We appreciate the degree of mental comfort it gave us when using it in an exceptionally wet summer season in the Sierra. We watched water bead off the coating with relief more than once in our floorless shelter, but we wonder how long this coating will last without being re-treated.
Overnight to week-long backpacking trips are what this bag does best. For truly long-distance thru-hiking, we would opt for an even more lightweight model. But for the majority of folks heading on backpacking trips, the Joule 21 is ideal.
The Joule is a decent value for your money and we agree that it is worth it to invest in a quality down bag like this model. It retails at just around $300. If you're looking for something that is not quite as warm, but will save a pound of weighing we'd recommend spending an extra $30 and picking up the Sierra Designs Women's Cloud 800
The REI Co-op Joule 21 is warm and relatively lightweight. It is a great choice for your backpacking adventures.
— Jessica Haist