The Sierra Designs Cloud 800 is a unique zipperless bag. Instead of a typical side-zip, it has a blanket fold on the front that tucks around a sleeper and keeps them warm. The fold can be tossed aside for more airflow in warmer temperatures. Rated for 35 degree nights and weighing 1 lb 7 oz, this bag was a top contender in our summer sleeping bag test. Ultimately, we think the Cloud is an excellent choice for someone in the market for a lightweight summer bag, but who doesn’t want to throw down the cash for an expensive Feathered Friends bag.
The Sierra Designs Cloud 35 stands out for being a zipperless sleeping bag. In our summer bag test, it is the only model to have this feature. Instead of a zipper, the top of the bag folds over like a comforter, which provides the sleeper with a lot of room and ways to moderate temperature and ventilation. The lack of a zipper reduces the weight and increase the compressibility. For $60 less than the Feathered Friends Flicker (or top-scoring summer sleeping bag) the Cloud is an excellent option for warm weather lightweight backpacking.
At 1 pound 7 ounces, the Sierra Design Cloud-800 is tied with the Feathered Friends Flicker for weight. For the same weight, the Cloud offers more features but is less warm. At under 2 pounds, we find that this bag is a pleasure to carry on summer backpacking trips where weight is a concerning factor. We brought it with us on an overnight into the Wind River Range in Wyoming, along with a lot of heavy climbing gear, and found that this lightweight bag was the perfect companion and helped to keep our overall pack weight down.
As a thin and lightweight down bag, the Cloud compresses into a small package. It is held back somewhat by the lack of a compression sack. It comes with a large storage bag and a smaller stuff sack, but that sack does not have compression straps. If packed into a true compression sack, we found that it gets quite small and becomes an insignificant item in your backpack.
If the night is warm and body heat needs to be dumped, it does not get much easier than tossing aside the top blanket fold of the Cloud. This is even more convenient than unzipping the side of a standard mummy bag like the Big Agnes Wiley. This does not allow for the entire length of the bag to be opened, but it does open wide about three-quarters of the way down. If that is still not enough ventilation, a generous opening at the foot of the bag allows more venting – toes can be poked out of the flap for immediate cooling. The lack of zippers does not reduce the ventilation of this bag at all. Rather, venting is made even easier thanks to the cleverly designed flaps.
Unfortunately, the Cloud-800 35 isn’t particularly warm compared with the other bags in this test. It feels thin and lacks the plushness of the Feathered Friends Flicker even though it weighs the exact same. The Flicker and most of the other summer bags in this review are rated down to 30-degrees, while the Cloud and The North Face Campforter are only rated to 35ºF. We can feel this difference when spending back-to-back nights in these bags; the Cloud is noticeably less warm. However, the Cloud is definitely warmer than the Therm-a-Rest Space Cowboy – the thinnest bag in our test – which is rated to a balmy 45 degrees. For warm weather camping, the lack of warmth in the Cloud is not a huge deal, and might even be preferable in sticky humid conditions. But this is not the bag we would want for stretching the temperature rating or to use into the shoulder seasons.
The Cloud is insulated with 800 fill Dri-down, meaning that the down is high quality, very compressible, and resistant to moisture. It will continue to retain its loft longer than non-treated down. This expands the conditions in which this bag will be comfortable and gives the user more confidence when experiencing condensation, light rain, or morning dew.
The features are what really makes this bag shine against its competition. The Cloud is designed without zippers. Instead, the top half of the bag has a crescent-shaped opening with a fold-over flap that mimics a blanket. It wraps around the sleeper just like a blanket in a regular bed would. We found this to be roomy, comfortable, and less confining than a standard mummy bag. This design also makes it easy to toss the blanket fold aside if it is particularly warm and fresh air is needed. If it is cold, there is a pocket that tucks around the shoulder to keep the blanket securely in place.
Unlike the Feathered Friends Flicker, which is hoodless, the Cloud has a hood with an incorporated cinch so that it can be tightened around the face to seal in warmth. This gives this nontraditional bag the advantages of a traditional mummy bag when the weather is cool. There is also a flap near the foot of the bag that allows toes to poke out if extra ventilation is needed. We used this feature for wearing the bag around camp. When socializing around a campfire, it is easy to slip into this bag and slide the feet out the bottom so the wearer can still be somewhat mobile while wearing the bag.
Lastly, the Cloud has a half-length sleeve for a sleeping pad to keep the bag in place on top of a camp mattress. Often we find features like this unnecessary because the sleeve simply adds weight and bulk, but for those who often roll off of their sleeping pads at night, this adds security and comfort.
Constructed with a lightweight 15-denier material, the Cloud is more fragile than the Feathered Friends Flicker, which features a slightly burlier 20-denier nylon, or the Nemo Ramsey, which is made with 30-denier shell fabric and an extra burly 40-denier foot box. The material feels flimsier to the hand than the material on most of the other summer bags we tested. We did not experience any rips or tears during our summer of testing, but we did feel that this bag was perhaps a little more vulnerable to tears than others. It is definitely more susceptible to leaking insulation through a small tear than with the Therm-a-Rest Space Cowboy or the Marmot Ultra Elite, the synthetic models in our summer bag review.