The Cosiest Two-Person Sleeping Bag Yet 

By Indefinitely Wild on at

By Wes Siler

Thanks to its shoe-style, zipper-free design, this new Backcountry Bed Duo from Sierra Designs packs bed-level comfort for two into a bag that's small and light enough to actually fit in a backpack. If you want to cuddle outside, this is the bag for you. Sadly, it's not as good as it could be.

Two-Person Backpacking Solutions, Or The Lack Thereof

If you like going camping with your partner, you know sleeping together has always been harder than it probably should be. Some 1P sleeping bags zip together; you can strap two sleeping pads together and there're various weird solutions around 2P sleeping bags, but nothing, absolutely nothing, has yet delivered comfortable, seamless, draft-free ease that doesn't make sex awkward and sleeping something you do separately.

When we're car camping, Lara and I have been using one of those giant, queen-size inflatable air mattresses and cheap, huge, rectangular, synthetic sleeping bags. The problem with that solution is its lack of both portability and relative warmth. Sleeping pads should be insulated for use in cold weather, and a giant air mattress is not. Rectangular bags, in general, struggle to seal in warmth at their tops and el cheapo bags like ours are nowhere near as warm as their temperature rating claims. Ours is a "zero degree" bag, and we get cold any time temperatures drop below freezing. And it weighs about 5 1/2 kilos while packing into the size of a small hippopotamus.

We've tried a few different solutions for backpacking. The Nemo Tango Duo Slim quilt impressed with its light 1.2kg weight and small packed size, but Lara slept cold in it, despite using a well-insulated pad. It also did nothing to bring the two pads together, resulting in an annoying gap between them. Separate-zip together bags are warmer, but still leave that awkward gap between pads and just sorta locate each of you in your own hemisphere. Most of the time, we just sleep in our own separate bags/pads. It kinda sucks having an amazing day together in the outdoors, then just kissing each other good night and sleeping separately.

The Coziest Two-Person Sleeping Bag Yet 

What's A Backcountry Bed?

Sierra Designs came out with an innovative new 1P sleeping bag a couple of years ago. Instead of the traditional side zipper opening that most mummy bags have, it enlarges the head hole into half your body length, then fills that with an oversize "comforter." Think of it as a shoe tongue design. The basic idea is that the design enables you to sleep in the same manner as you do at home — on your side, your stomach or your back, with the comforter pushed down, pulled up, half-off or tucked in tight. That comforter is down-filled, sewn to the sleeping bag at its bottom and larger than the opening, making it easy to tuck it in all the way around for maximum warmth.

There's other clever, comfort-oriented features too, including mitten-like pockets for your hand in the comforter's corners, an integrated pad sleeve to keep you on top of the sleeping pad as your roll around in the night and even a vent beneath your feet through which you can poke those out on warm nights and which self-seals on cold ones to keep you draft free.

It is a bag that prioritises comfort over portability though; being a bit larger and heavier than an equivalent traditional mummy and I still prefer the Big Agnes system because it delivers even more comfort in a smaller, lighter, higher quality package.

The Coziest Two-Person Sleeping Bag Yet 

Now For Two

For 2015, Sierra Designs has increased the Backcountry bed to 2P size in two flavours. There's a synthetic version that weighs a little more, packs a little bigger and doesn't insulate as well, but costs just $250/£162. Or, the down version we tested that weighs 1.8kg, is rated to freezing and retails for $500/£324.

You get all the same features as the 1P Backcountry Bed, plus two pad sleeves on its underside. Those are where the real genius of the design begins; the sleeves can accept standard 20-inch wide or more luxurious 25-inch pads if you undo the buttoned gussets. That arrangement also allows you to mix a 20 and 25 together. Regardless of pad size, they're squeezed tightly together. It's not a one-pad solution, but the pad gap is minimised as much as two separate pads can ever be thanks to that tight squeeze.

The comforter also makes getting in and out of the bag and interacting once you're in it a much easier affair; akin to sleeping under your comforter at home. It's hard to quantify the advantages of this arrangement in words, but "it just works" should suffice. The unified mummy hood helps retain both partners' head heat and the whole thing just feels super cosy and unified.

We didn't use backpacks in Death Valley this weekend, but the 600-fill down packs just about small enough to fit in one. If one of you carries it and the other carries your tent, you'll be fine.

The Coziest Two-Person Sleeping Bag Yet 

Still Not Ideal

But, even with a minimised pad gap and bed-style design complete with mummy hood, this bag is still a long ways from perfect. For its price, I'd think a lighter, warmer, more compressible 800-fill down should have been used. This could have resulted in a lighter bag with a smaller packed size that could be warm down to about -7 degrees C. That's a much more versatile temperature rating that's exactly what you need for most backpacking trips in the mountains.

And, that size, weight and cost could be further diminished by adopting Big Agnes' full-length pad sleeve arrangement that eliminates the need for insulation on the bag's underside. The foot vent is not an often-used feature anyway and squeezing the pads together for the full length of the bag would be a very welcome improvement that would increase stability, better unify each person's space and allow the bag to remain totally planted as you, um, move around vigorously inside it.

All that, plus a true 2P sleeping pad is what's needed for a total reinvention of the couples camping sleep system. Sierra Designs is owned by Cascade Designs; the same parent company as Therm-A-Rest. A 2P version of the Therm-A-Rest NeoAir All-Season would seem like a home run product, giving couples a light, easily packable, warm, durable and comfortable sleeping surface and integrating that into a full-length, purpose-designed sleeve in a backless Backcountry Bed would create a near perfect system. Make it happen guys, spreading the ability to have good sex on an epic adventure is a worthy cause.

Until then, Lara and I will be augmenting this bag's warmth by using that Nemo quilt as an overbag. Combined with insulated pads, that takes us down to what's likely a genuine -10 degree comfort level and gives us the ability to carry only as much warmth as we need. But, at $1200/£777 or so with pads, that's a system that's just too expensive for most people. Why can't we all just get along inside warm, light, comfortable 2P sleeping bags?