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June 2022 Issue
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Sierra Designs Cloud 35



Our Rating:

660g /-3°C limit

Features: A zipperless design, the Cloud 35 relies instead on two overlapping insulated layers on the upper half of the bag. There is no down in the centre upper back of the bag – because it gets squashed anyway – but a half-length sleeping pad sleeve allows smooth integration with a mat. There’s also a ‘self-sealing’ foot vent. The bag is filled with 294g of 800 fill power water-resistant down.  

Fit: This model is available in regular or long. The regular size fitted my slim 176cm frame comfortably, with wiggle room in the legs and little wasted space in the hips and shoulders. A person of larger build would find it quite a cosy, thermally efficient fit. 

Comfort: On face value this is a very comfortable sleeping bag. The design uses a ‘comforter’ down-filled panel that extends across the chest and shoulders, while another partially overlapping panel sits on top of that. The lack of zipper means that when lying on your side with the bag pulled up around you, there’s no zip getting in the way – just smooth nylon and plush down. This also makes it quick, easy and quiet to get in and out of. 

In use: While the comforter design is unquestionably cosy, it did not work reliably in every sleeping position. If I lay on my back or left side, it wrapped reassuringly and felt snug; however, when I rolled to my right side during the night it sometimes fell open a little, which noticeably cooled me down. Because there is no down in the upper back of the bag, it’s crucial to use the mat sleeve to secure the bag to your mat; however, because there is no anchor for the toe of the mat, I did find that on sloping ground the mat had a tendency to partially slide out of the sleeve. The foot vent allowed me to poke my feet out for cooling, and the overlap was effective in preventing a cold spot. 

Value: Compared with other similar bags by temperature rating and fill power, it’s among the lightest options you will find for this price. 

Verdict: Versatility is probably this bag’s greatest feature, brought about by its novel closure system and foot vent. While the closure system might be a compromise in one way, when working well it’s very cosy and also allows the top half of the bag to be opened wide on warm nights. While we’ve suggested it for summer use, minimalists could stretch it to early autumn/late spring conditions. 

Plusses: Light for its warmth, comfortable, well priced, very well made
Minuses: May not be the best for right-side sleepers