The Sierra Design Cloud 800 sleeping bag is zipless with an oversized wraparound concept. It looks like a combination of a sleeping bag and a blanket and the idea is you can have it folded over and tucked around you for warmth, or opened up for airiness. There is also an unusual footbox with a “patented self-sealing foot vent”. It takes the form of a slit at the rear of your ankles. Oddly, the top of the rear of the bag is also hollow of down. There is a large flap for slotting in an inflatable mattress and perhaps the designers felt there was no need for down here but it feels a bit lacking.

Fiona Russell’s verdict

The issue for me is that it’s a bit of an investment to discover whether you’ll love or hate the bag, however, it’s good to see designers being innovative.
Pros
  • Comfort
  • Weight
  • No zip
Cons
  • Noisy
  • Stuff bag
  • No zip
Quick specs
Price: £299.99
Weight: 1099g (reg) 
Fill: 419g 800FP PFC-free, responsibly sourced DriDown
Shell and liner fabric: 15d nylon ripstop, PFC-free water-repellent coating
Construction: box wall, stitch through
Zip: Zipless 
Length: 198cm (reg), 213cm (long)
Rating: comfort -3C, limit -10C
Sizes: Regular, long
Women/Mens version: unisex

I think you will either love or loathe the design of the Sierra Design Cloud 800. I liked it to start with but then, in the middle of the night, it felt draughty. I must wriggle a lot because I ended up in quite a tangle in the bag, unable to find the end of the flap to wrap over me and with one foot in the footbox and another out. 

Meanwhile, when I lent it to my husband to try, he loved it. He said it was great for getting a good balance of warmth and breeze. He also really liked that he could slip his feet out of the bottom of the bag when they felt too warm. 

Aside from the design, the Sierra Design Cloud 800 feels light and airy. It’s the second lightest bag I’ve tested but it is still comfortably warming even during chilly nights (when it wasn’t letting in a draught). The nylon fabric rustles a it when you move and it’s almost see-through in places, yet it still feels robust.

The bag ticks an ethical box thanks to responsibly sourced down that’s trackable via a Track My Down portal (https://trackmydown.com/). It also has an environmentally friendly PFC-free water-repellent treatment that’s useful for keeping off the inevitable damp of camping outdoors.

The stuff bag for packing is adequate but not good for compressing the sleeping bag, while there is a useful large mesh sack for longer-term storage.

The issue for me is that it’s a bit of an investment to discover whether you’ll love or hate the bag, however, it’s good to see designers being innovative.


Written and tested by Fiona Russell

Fiona Russell is 5ft8in tall and slim. She is also a cold sleeper. She has tested the bags in a range of overnight temperatures while wild camping.