ActiveOutdoorsSierra Designs Cloud 800 20 review: cleverly designed zipless sleeping bagThe Sierra Designs 800 20 is all designed to make nights in the great outdoors more comfortable – no zips required!When you purchase through links on our site, we may earn an affiliate commission.Here’s how it works.(Image credit: Matthew Jones)T3 VerdictAn unusual and innovative sleeping bag with a unique design, high-quality down fill and excellent ventilation options, the Sierra Designs Cloud 800 20 is likely to polarise opinions.Reasons to buy+Plenty of room for wriggling around in the bag+Excellent weight-to-warmth ratio+Zipless design prevents zip-related issues+Clever foot vent helps dump heatReasons to avoid-May not suit side sleepers-Requires a good sleeping matWhy you can trust T3Our expert reviewers spend hours testing and comparing products and services so you can choose the best for you.Find out more about how we test.
ActiveOutdoorsSierra Designs Cloud 800 20 review: cleverly designed zipless sleeping bagThe Sierra Designs 800 20 is all designed to make nights in the great outdoors more comfortable – no zips required!When you purchase through links on our site, we may earn an affiliate commission.Here’s how it works.(Image credit: Matthew Jones)T3 VerdictAn unusual and innovative sleeping bag with a unique design, high-quality down fill and excellent ventilation options, the Sierra Designs Cloud 800 20 is likely to polarise opinions.Reasons to buy+Plenty of room for wriggling around in the bag+Excellent weight-to-warmth ratio+Zipless design prevents zip-related issues+Clever foot vent helps dump heatReasons to avoid-May not suit side sleepers-Requires a good sleeping matWhy you can trust T3Our expert reviewers spend hours testing and comparing products and services so you can choose the best for you.Find out more about how we test.
The Sierra Designs 800 20 is all designed to make nights in the great outdoors more comfortable – no zips required!
When you purchase through links on our site, we may earn an affiliate commission.Here’s how it works.
(Image credit: Matthew Jones)T3 VerdictAn unusual and innovative sleeping bag with a unique design, high-quality down fill and excellent ventilation options, the Sierra Designs Cloud 800 20 is likely to polarise opinions.Reasons to buy+Plenty of room for wriggling around in the bag+Excellent weight-to-warmth ratio+Zipless design prevents zip-related issues+Clever foot vent helps dump heatReasons to avoid-May not suit side sleepers-Requires a good sleeping mat
(Image credit: Matthew Jones)
(Image credit: Matthew Jones)
T3 VerdictAn unusual and innovative sleeping bag with a unique design, high-quality down fill and excellent ventilation options, the Sierra Designs Cloud 800 20 is likely to polarise opinions.Reasons to buy+Plenty of room for wriggling around in the bag+Excellent weight-to-warmth ratio+Zipless design prevents zip-related issues+Clever foot vent helps dump heatReasons to avoid-May not suit side sleepers-Requires a good sleeping mat
T3 VerdictAn unusual and innovative sleeping bag with a unique design, high-quality down fill and excellent ventilation options, the Sierra Designs Cloud 800 20 is likely to polarise opinions.
T3 Verdict
An unusual and innovative sleeping bag with a unique design, high-quality down fill and excellent ventilation options, the Sierra Designs Cloud 800 20 is likely to polarise opinions.
Reasons to buy+Plenty of room for wriggling around in the bag+Excellent weight-to-warmth ratio+Zipless design prevents zip-related issues+Clever foot vent helps dump heatReasons to avoid-May not suit side sleepers-Requires a good sleeping mat
Reasons to buy+Plenty of room for wriggling around in the bag+Excellent weight-to-warmth ratio+Zipless design prevents zip-related issues+Clever foot vent helps dump heat
Plenty of room for wriggling around in the bag
Excellent weight-to-warmth ratio
Zipless design prevents zip-related issues
Clever foot vent helps dump heat
Reasons to avoid-May not suit side sleepers-Requires a good sleeping mat
May not suit side sleepers
Requires a good sleeping mat
Why you can trust T3Our expert reviewers spend hours testing and comparing products and services so you can choose the best for you.Find out more about how we test.
Why you can trust T3Our expert reviewers spend hours testing and comparing products and services so you can choose the best for you.Find out more about how we test.
Jump to category:Price and release dateSpecificationsDesign and build qualityComfort and performanceVerdictAlso consider
Jump to category:Price and release dateSpecificationsDesign and build qualityComfort and performanceVerdictAlso consider
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The Sierra Designs Cloud 800 20F is a three-season 800-fill power-down sleeping bag that is warm enough to deal with temperatures below freezing, with a comfort rating of -3°C (or -6°C for the women’s version). It has an excellent warmth-to-weight ratio that ensures this bag is competitive in both weight and packability for a bag of this class, making it one of the bestlightweight sleeping bagsout there.
However, the Cloud’s real USP is its unusual zipperless design – which will appeal to anyone who’s ever struggled with a jammed sleeping bag zipper or woken up hot and sweaty in a tent with their bag wrapped around them. It also offers plenty of other features that ensure this bag stands out from the pack, including an integrated sleeve for your sleeping mat or pad, a self-sealing vent, and a quilt-like flap or ‘comforter’ designed to feel just like you’re sleeping under your duvet at home.
Sierra Designs Cloud 800 20 review
Sierra Designs Cloud 800 20 review: price and release date
The Sierra Designs Cloud 800 20 is available to buy right now directly fromSierra Designswith prices from $340/ £300 (approx. AU$ 539) for the regular length version. It is available in both standard and long lengths in men’s and women’s versions.
Sierra Design has other zipless sleeping bags, some cheaper than the Cloud 800 20. These include theNight Cap 20, a more affordable, responsibly-made version of the Cloud that still packs down to a backpack-friendly size. It’s sold for just $200 for the standard version.
Sierra Designs Cloud 800 20 review: specifications
(Image credit: Matthew Jones)
(Image credit: Matthew Jones)
Sierra Designs Cloud 800 20 review: design and build quality
(Image credit: Matthew Jones)
(Image credit: Matthew Jones)
Sierra Designs has taken a different approach from most other sleeping bag manufacturers when it comes to their down-filled Cloud series. Rather than adopting the nearly ubiquitous zippered mummy-style cut, these have an unconventional zipperless design. Instead of a full or half-length zip, there’s a half-length quilted flap (or comforter, in American parlance), which has a 3D-sculpted shoulder pocket to help keep it wrapped around you. It makes for an extremely comfortable bag. The rest of the bag is similarly focused on comfort, with a roomy and oversized fit.
There’s also a clever foot vent to help dump heat if it gets too toasty. This has a stitched flap over the opening to ensure it self-seals, but it is easy to kick your feet out through the hole if you start to overheat. This adds versatility for camping in milder conditions, as does the comforter, which is easy to throw aside – certainly far more practical than trying to unzip most sleeping bags, which inevitably snag at the most inconvenient moment.
So, instead, there’s a rear sleeve to accommodate your sleeping mat. This makes it impractical to twist the bag around, so it may not suit side sleepers – though the roomy fit makes it relatively easy to move around inside the bag itself. It does, however, mean that you really need a well-insulated sleeping mat underneath you to guarantee you stay warm.
Still, it’s a clever weight-saver – despite its luxurious construction and accommodating dimensions, this bag weighs in at under a kilo. The pack size is competitive, too, and all in all, it’s a good value package.
Sierra Designs Cloud 800 20 review: comfort and performance
(Image credit: Matthew Jones)
(Image credit: Matthew Jones)
In colder conditions, when overnight temperatures started to approach freezing, we did start to get cold – but here, the mat was the culprit, not the bag. Upgrading to a warmer mat (in our case, a NEMO Tensor Insulated pad, with an R-value of 4.2) hugely extended the viable temperature range of the Cloud 800 20F.
This experience simply reiterates the point that it is essential to pair this bag with a decently warm mat. That’s true of most sleeping bags, of course, but the fact that this particular model has zero down filling on the underside makes it absolutely critical. It’s also worth checking that if you already own a sleeping mat, it will fit inside the Cloud’s integrated sleeve.
This will accommodate any mat up to 20 inches wide and 2.5 inches thick (or 51 x 6.4 cm in metric dimensions). You can also get away with using a narrower but thicker mat, provided its overall circumference doesn’t exceed 45.5 inches (approx. 115 cm). The optimum mat would be approx. 50 cm wide, though, as this effectively prevents the mat from sliding around inside the sleeve.
Sierra Designs Cloud 800 20 review: verdict
(Image credit: Matthew Jones)
(Image credit: Matthew Jones)
The Sierra Designs Cloud 800 20 adopts an undeniably innovative design approach. The use of zoned down fill, and the lack of a zipper are both good weight savers, which means that the Cloud can utilise a roomier, more comfort-focused fit without adding excess weight or bulk to the overall package.
We also like the added ventilation options, which add versatility for use across a range of different seasons and temperatures. Some will find it an absolute dream to sleep in. Others might not get on with its unusual design so well, though, and we reckon it’ll prove to be a bit of a Marmite product – you’ll either love it or hate it.
Sierra Designs Cloud 800 20 review: also consider
There are any number of other 800FP down three-season sleeping bags on the market, including various models from highly regarded brands like Rab, Mountain Equipment, Therm-a-rest and Sea to Summit, as featured in T3’sbest sleeping bagguide. Most, however, are either zippered mummy bags or, in a few cases, zipperless backpacking quilts.
There’s nothing else on the market that uses the ‘zipperless bag’ approach of the Cloud 800 – though Big Agnes’ Sidewinder SL20 is another bag specifically designed with side sleepers in mind.
Similarly, NEMO Equipment’s spoon-shaped Forte, Disco and Riff sleeping bags are also intended to accommodate side sleepers, offering some extra room at the hips, knees and shoulders. All these are worth considering if you find traditional zippered, mummy-style bags restrictive or uncomfortable.
Sierra Designs Cloud 800 20F: Price Comparison
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