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#88112 - 01/26/08 10:41 AM WARM in DOWN
Jimshaw Offline

Registered: 10/22/03
Posts: 3939
Loc: Bend, Oregon
Hi All,
The subject here is "warmth of down garments relative to "loft" and "Shell stiffness"" <img src="/forums/images/graemlins/grin.gif" alt="" />.

Just before I start - remember its the fleece and longunderwear that keep you "cozy" warm, not the down. <img src="/forums/images/graemlins/smirk.gif" alt="" />

Down is a great insulater used in the right application Its the tiny pockets of air in the down that hold air still so it can be warmed. Let the air move around and those tiny pockets are no longer warm. Holding the air still in those pockets, and how thick the "virtuala" insulation layer is determines how warm a garmet will be. The virtual thickness of a garment depends on the ability of the shell to resit deformation. <img src="/forums/images/graemlins/smile.gif" alt="" />

The worst offenders are over jackets that compress the down around shoulders and chest, and backpack straps. There is mostly NO INSULATION in a high number down garment (800 down) when there is any weight on it at all. <img src="/forums/images/graemlins/blush.gif" alt="" /> <img src="/forums/images/graemlins/confused.gif" alt="" />

Down jackets with UL shells flap in the wind and are COLD. WHY? Because the 800 down does not have enough "body" to retain the shape "virtual thickness" of the garment, AND because the shells are made of very gossamer fabric.

A 650 down jacket (ignoring weight) can be warmer than an 800 down jacket - remember the number refers only to the first order "loft" and is not a measurement of "warmth", in fact commercially it means "Use less down". When you buy 800 down you are buying less down for more - light but not warm.

An 800 down UL sleeping bag is nice in a shelter, but could flap in the wind if exposed to wind and be worthless. <img src="/forums/images/graemlins/mad.gif" alt="" />Also if your pad goes flat 800 down offers little insulation under you. <img src="/forums/images/graemlins/blush.gif" alt="" />

My 700 down WM Super Kodiak with goretex shell weighs 1 pound more than a new modern one with 800 down and a UL shell - and in a sheltered space they may function similarly. <img src="/forums/images/graemlins/smirk.gif" alt="" />
I would bet that my OLD Kodiak bag would be a MUCH warmer haven in an exposed environment, than the new UL Kodiak would be. <img src="/forums/images/graemlins/grin.gif" alt="" />

Its a matter of the UL thing pushing manufacturers to make what people want, not what people need. <img src="/forums/images/graemlins/blush.gif" alt="" /> Fortuately in this country we have people who live where its cold and places like Cabelas and Bean still manufacture reasonable warm functional inexpensive gear that will outperform the ultraexpensive UL gear in every way but weight. <img src="/forums/images/graemlins/smirk.gif" alt="" />

Take my jacket collection for example. By modern standards my jackets are made of iron for a knight of the round table, but just try to find a rugged fully technical randonee jacket with powder skirt, double zippers, adjustable neck and high pockets for wearing with a pack thats UL. <img src="/forums/images/graemlins/smile.gif" alt="" /> You can't get that much function that light - period.

You will get more function from "regular weight" technical wear than from UL gear with the bells and whistles left off. UL is about going without. But going without warmth or waterproofness is not reasonable in a cold weather garment.
Jim <img src="/forums/images/graemlins/cool.gif" alt="" />
These are my own opinions based on wisdom earned through many wrong decisions. Your mileage may vary.

#88113 - 01/26/08 10:55 AM Re: WARM in DOWN [Re: Jimshaw]
Bearpaw Offline

Registered: 07/25/04
Posts: 1732
Loc: Tennessee
I've actually noticed this in both jackets and sleeping bags.

I'm a big guy. Thus I tend to find fit snug in most comercial bags. In every bag or jacket where there is any compression, I immediately notice chill in any place where the down is high-loft. With bulkier jackets, well, they don't compress so much at the shoulders, and I don't get chilled.

My solution has been simple. My fiancee and I sat down and made an 800+-down quilt that was actually big enough to fit me well. It is as big and heavy as a typical bag, but is made to be open beneath me. With no compression, it keeps me remarkably warm. I figured it was good for maybe 20 F, but slept in a tarp with a UL bivy around it down to around single digits back on New Year's day. BTW, this was under a tarp, not inside a tent.

Ligh-loft down has its place, and is very helpful for watching weight and bulk, but it does requires special consideration in its use.

#88114 - 01/26/08 12:33 PM Re: WARM in DOWN [Re: Bearpaw]
Earthling Offline

Registered: 02/22/03
Posts: 3228
Loc: USA
I agree with what both of you guys have posted and add; that it also depends on the intended use of the item in question. that is why it is so hard to pin down, pun intended <img src="/forums/images/graemlins/smirk.gif" alt="" />, which bag, jacket, etc made in which loft down will work for a poster. If they are sleeping in shelters nude in their bag then it may be fine; if they venture out of the shelter, then they are probably going to feel a bit of 'wind chill' effect IME. It's a very complicated question that is so often poised simply <img src="/forums/images/graemlins/tongue.gif" alt="" /> <img src="/forums/images/graemlins/confused.gif" alt="" />

#88115 - 01/26/08 07:27 PM Re: WARM in DOWN [Re: Jimshaw]
wandering_daisy Offline

Registered: 01/11/06
Posts: 2797
Loc: California
For me it is fit, fit, fit! And construction details. Opposite of Bearpaw, I am on the small side so it is hard to find stuff that fits. I never wear a down jacket backpacking so the shoulder strap compression is not an issue. Even when I did winter trips in below 0F we only wore wool union suits and a wind suit when carrying a pack. I have problems with sleeves that are too wide (wind gets in) and sleeping bags too wide in the lower leg area. Big issue also are zipper flaps - they need to be sufficiently large. And I would not have a bag without a collar. I do not think it makes much difference if you have 650, 750 or 900 down in a bag, the bottom warmth is all about your sleeping pad anyway. I have a 750 WM Super Antelope (with dry loft) and my problem is that it is too wide. They say it is a 10 degree bag, but for me it is a 20 degree bag. I had a Marmot Aguille 750 5-degree bag (got stolen) that had a very narrow cut and I really liked it better. I would not buy a bag with dry loft cover again. It adds $100 to the cost and I never camp out in the open anyway because I hate to get my bag dirty.

I am not willing to pay the extra $$ for the 800-900 down. The 750 stuff is fine for me. All my friends like the synthetic "Puff-Ball" jacket - I am really leaning toward that for replacement when my down jacket dies.

#88116 - 01/26/08 09:47 PM Re: WARM in DOWN [Re: wandering_daisy]
OregonMouse Online   content

Registered: 02/03/06
Posts: 6560
Loc: Gateway to Columbia Gorge
I've always had this gut feeling that because I have a down sleeping bag, I should stick to synthetic clothing. While I take extra care to keep my gear dry, I still feel more comfortable not having all my insulation of the same material.
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey

#88117 - 01/27/08 05:29 AM Re: WARM in DOWN [Re: Jimshaw]
Dryer Offline

Registered: 12/05/02
Posts: 3585
Loc: Texas
I own one down jacket (I talk about that in your other down jacket thread) and I don't backpack or hike with it. Not because of compression but because layering is all but impossible with down jackets. If we're just talking about standing around in the cold, I find down and heavy wool to be warmest for me. Things like watching a cold soccer game with my kid's, or fishing,...inactive stuff. Leather jackets are worthless.... <img src="/forums/images/graemlins/smirk.gif" alt="" />
For hiking, I need the ability to shed or add layers.

Caveat about down...and the way I use down while hiking....many times after breaking camp, usually in the dark, and the morning chill is still in my bones, I've wrapped myself in my down quilt or bag and hiked on, or enjoyed breakfast. As long as there's no bushwhacking or snags, that quilt or bag covers me head to toe and is crazy warm until I "warm up". Then it gets stuffed in the pack. A down 'robe' is a good description. I suspect we've all done this at one time or another.

None of my 5 down bags are over 700 fill power and my favorite bag was bought in 1984 and is 650fp. It's still my favorite, has been machine washed and dried countless times, and is still as fluffy as new. It's an old TNF Chrysalis that's now a quilt (zipper mods). I've often wondered if high fill powers like 900 don't eventually settle down to the 6-700's after a few years of closet life. With any piece of backpacking gear and it's UL factor, there's a line between utilitarian and UL. Heavier fabric does crush higher fill powers. Lighter fabric won't hold up.
If we're wanting the lightest of everything, Aerogel and mylar would be the way to go, but you only get to use it one day. <img src="/forums/images/graemlins/grin.gif" alt="" />

All that said, I've never been colder than -5 F in my whole life and hike mostly desert, which has wild swings in temperature. I can't speak for you mountain/snow people. Down may be THE thing there. I've been caught out in snow...happily and gratefully....but never hiked it on purpose.
paul, texas KD5IVP

#88118 - 01/27/08 08:54 AM Re: WARM in DOWN [Re: Dryer]
Hector Offline

Registered: 12/20/04
Posts: 325
Loc: LA/ARK/TX corner
All that said, I've never been colder than -5 F in my whole life and hike mostly desert, which has wild swings in temperature. I can't speak for you mountain/snow people. Down may be THE thing there. I've been caught out in snow...happily and gratefully....but never hiked it on purpose.

Never been out below the twenties -- have never been in an area where it was into single much less negative digits -- and the only down I take in a pack is the sleeping bag (BA Mystic long, 725 down). Only been out in snow once, which didn't stick, just obscured visibility, stung the cheeks, made things wet. No winter wonderland that. Didn't like it.

I just lost my best jacket, which was my old motorcycle coat but got too ragged to wear on the road. Light, windproof, fleece lined, very warm, but I finally had to admit it was getting to be more duct tape than nylon. I'm looking. Only wore it in camp.

I do have a down jacket. I use it on very cold days going to work, where it's shirt-sleeve warm inside so I don't need layers. Anything but a tee-shirt under the down and I overheat even in very cold conditions (which down here is around freezing for the most part). If it gets a little chilly, as has happened when I had to visit a jobsite, I toss a rain coat on over it, which really boosts the warmth.

So, in conclusion to this inexplicably long-winded rambling, down is too warm to wear down here for the reasons you touched on. I need to be able to layer, and down defeats that -- it's always too warm to wear while actually walking -- and I don't want to haul it just to wear it in camp. Great to have when car camping, though.


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