New Ultralight Summer Sleeping Bags

Global warming means I never know what season I'm in any more.

But I can say this for sure: summer is when you're only willing to carry a 500 gram sleeping bag.


This year I've been sleeping better with an ultralight wrapped around me. It's the down Siren from Nemo Equipment. It's as pretty as a backless dress and designed like one too.

At 530 grams of 850-fill power down, it's rated below freezing if you cinch it up completely. The bag has a wide temperature range if you drape it loosely like a duvet and layer up or down underneath.

I tested this versatility recently on the AT, on nights ushered in by warm winds, followed by cold storms that cleared 'round midnight. Near dawn, it started to rain again.

At bedtime I slipped my insulated Exped DownMat into the foot of the bag and drew in the drawstring beneath the sleeping pad to wrap it loosely around the sleeping pad. I snuggled into a Thermax liner and wiggled in, drawing my covers up loosely around my chest. During the night, there were always plenty of covers to burrow beneath.

The Siren is luxuriously quiet. Its wraparound design meant that I never once slid off the pad. The quilt concept offers near boudoir-quality freedom of movement. I drifted awake almost certain I was in a bed, not in a tent.

Western Mountaineering makes an even lighter summer quilt (411 grams), rated to 40F, that practically disappears in your pack or pannier bag and unzips fully for hostel use. It's not as pretty, not as soft and not as quiet as Nemo's Siren. What is? But the Western will be my low-elevation summer bedmate after May day.

Down insulation: still warmest for its weight.
Still the most packable. Still the most comfortable.
Pricey and high maintenance, but worth it.
I wish all manufacturers certified their down like Patagonia does....

Best Air Mattress

I’m getting a great night’s sleep now that I’ve switched to the DownMat UL by Exped.

The definition of a good night's sleep.

At 580 grams, it’s half a pound heavier than my Thermarest NeoAir. They pack down to about the same size. Compare the gain in insulation and decide for yourself if it’s worth it. The NeoAir has an R value of 2.5. The DownMat: 5.9. That’s twice as warm. 

And, as one Himalayan guide had promised me, the DownMat is by far the most comfortable sleeping pad I’ve ever tested. 

 The stuff sack doubles as the pump.

Never take the DownMat on a trip without a good repair kit. Like all air mattresses, it’s useless uninflated. But unlike most air mattresses, you can’t fill this up with the humid air from your lungs. You'll wet out the down.

So you need the roll-top yellow pump, which is quite cleverly designed, but if that gets a puncture, you’re s**t outta luck. If you've been doing the math, your odds of a puncture that will leave you sleeping on the bare ground have just doubled. Bring the repair kit! I'm thinking about buying a second pump bag as backup. It’s as light as any other stuff sack on the market. And the UL air pillow that inflates with the same pump takes up less space than my face towel. 

Who needs an air pillow? Who needs a down insulated sleeping pad? Isn't this all just over the top?

That’s what I was mumbling before I spent a month’s worth of freezing nights in Idyllwild during a cold snap. I was “luxuriously” bunked on a twin-bed size, 9-inch Kelty base camp mattress that leaked every night. It was cold as f***. I’d brought along my NeoAir for the peaks, and I froze my ass on that, too.

So fibers and feathers do make a difference. They block cold spots. They’re warmer and more comfortable than foam (whether closed cell or open cell). If you can stomach the ticket price, splurge on an Exped and don’t look back. The DownMat is filled with IDFL certified down that's humanely sourced.

Here's a great shot of Exped in use by the UK blogger Robin. I like his helpful gear reviews. And I'm often jealous of his camp sites in the Fells, Wales and Scotland.


Down or synthetic? 

I compared the DownMat UL to its synthetic counterpart on Cumberland Island, Georgia, not known for its dry climate. They were equally warm and equally comfortable on nights that dipped down to about 45 degrees Fahrenheit.

The SynMat, filled with fairly eco fibers, inflates a bit stiffer, and the fabric feels a bit warmer to the touch. Paddlers might not want to test what happens if too much damp air is repeatedly pumped into the DownMat. But for trekkers and climbers, the hefty weight and the burly size make the SynMat a purely base camp mattress. I’d never carry it on a multi-day trip.

Exped MegaMat: base camp heaven

Some day, though, I’ll want that twin bed back. Think I’ll try the MegaMat. By then, maybe they'll make a double. That's down filled. Ahhh. Zzzzzzz.