What sleeping bag should I bring on a Denali climb?
What type of bag would you recommend for climbing Denali? Down or Polarguard insulation? What specific bag would you recommend? What about as far as clothinglayers, brands, models etc.? Would you recommend a full down suit? Or a down jacket and either down pants or a shell with layers? Bob Grish Boise, Idaho
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Depends a little bit on the time of the year. For a May or June climb, down is definitely the way to go. Lighter, less bulky and warmer for the weight than a synthetic. July - which is pretty late in the season there - is a little harder call. I can be warm and wet lower down on the mountain, and a good synthetic bag might prove useful. Still, higher up it will be cold, and even if a down bag gets damp, my experience is that there’s enough sun and solar radiation (plus lower humidity the higher you go) to dry things out quickly.
So, the question becomes: What bag? As a rule of thumb, a bag rated to -20 degrees would be about right. Good down-filled candidates include Marmot’s Col ($599), Feathered Friends’ Ptarmigan ($550), or Western Mountaineering’s Big Horn Super MF ($530). All are tremendous bags, well made, with high-loft down. Marmot and Feathered Friends use a water-resistant shell material; Western Mountaineering a breathable polyester that I think is a bit better for super-cold weather.
In the synthetic camp, I’d recommend Mountain Hardwear’s Fifth Dimension ($325), rated to -25. But, it weighs nearly seven pounds, versus about four pounds or less for the down models. So that’s the penalty.
My advice also is to take a vapor barrier liner as a supplement if needed. And two pads - an inflatable pad such as a Therm-a-Rest, and a closed-cell foam pad. And take both with you up to 17,000 feet. Even though you’ll be tempted to save a pound and leave one behind, you’ll be sorry if you do.
The down suit question again depends on time of year. For May, full down will be extremely useful. When I climbed the West Buttress in June, I was fine with heavy Polartec pants under Gore-Tex bibs, and a Feathered Friends down parka. The suit versus jacket/pants question is sort of a matter of taste. A suit is warmer and weighs less than a jacket/pants combo, but is less versatile. Generally, I think separate garments give you more wear flexibility, and almost the same performance as a suit.
Good luck! Let us know how you do.