I would like to know whether a down vest or a down jacket would keep me warmer, assuming they both have the SAME amount of fill.

In theory, focusing all the down on the torso area should keep you warmer, since that is where most of your major organs are.

However, it seems to me that if you do not insulate your arms, the blood that goes through them will cool down significantly. Being that your body will pump cooler blood into your torso because of uninsulated arms, this may mean you end up warmer in a jacket. Obviously I'm not a doctor, so I don't know if this is how the body works.

Let me hear your input.

-Sid

Edited by Red_Fox on 11/29/2009 10:07:11 MST.

The vest would stave off death from hypothermia longer seeing as blood stops circulating to the extremities as heat retention becomes a necessity. As for being more comfortable having a warm upper body is nicer than a warm torso. Also having working blood filled arms and fingers could do more to help save you from a situation in which you were reliant on your layers for survival.

I don't know but I can sure tell you that I much prefer a vest over a jacket during physical activity.

"I don't know but I can sure tell you that I much prefer a vest over a jacket during physical activity." -Evan Szakacs

As do I Evan. However, I hardly ever need insulating garments while I'm hiking. Only in very low temperatures have I ever needed to put on a jacket while hiking. I'm more interested in knowing what will keep me warmer while not hiking.

-Sid

It depends.

Presuming the arms take 1/2 as much down as the torso:

Bare arms and 3" of down vest over torso v. 2" insulation everywhere I say go for the jacket.

100 wt pile everwhere plus 3/4" down over torso v. pile + 1/2" down everwhere I say go for the vest.

The thing I've always noticed about wearing a puffy vest is that it's hard to prevent drafts from pumping out through the arm holes. I imagine you lose a lot of insulating efficiency.

Montbell made (or still makes) a down t-shirt or short sleeved jacket that is reported to deal with this problem. so maybe if you had a vest with short sleeves, say mid bicep, and the same weight of down as the jacket it would be more thermally efficient.

a jacket with full arms retains a lot more heat and you can unzip the torso to ventilate if need to cool down.

"The thing I've always noticed about wearing a puffy vest is that it's hard to prevent drafts from pumping out through the arm holes. I imagine you lose a lot of insulating efficiency.

Montbell made (or still makes) a down t-shirt or short sleeved jacket that is reported to deal with this problem. so maybe if you had a vest with short sleeves, say mid bicep, and the same weight of down as the jacket it would be more thermally efficient." -Joshua Gilbert

You make an excellent point Josh. I never thought of that. I will have to look into down t-shirts. It seems like a good compromise between a vest and a jacket. A down t-shirt with a half zip would probably be pretty light too. Maybe I can get the folks at Nunatak to make me one.

-Sid

You don't need to chose between vests and jackets...You can have it all, or not,,,

A down vest and JRB Down Sleeve makes a down jacket... Want a parka? Just add the JRB Down Hood... Wear each piece seperately or combine as desired.... hooded vest makes an ideal sleep top for quilt uses as the hood now moves with you and not the quilt or hoodless bag... Sleeves separate for use as sleep socks... Both extremities taken care of for improved sleeping...

Weightexample: Montbell Ex Lt Down Vest 4 oz, JRB Down Sleeves 5 oz (down jacket thus 9 oz)...JRB Down hood 2 oz ( Down Hoody thus 11 oz)

Remenber I'm biased.

Pan

A vest W/the SAME ounces of down as a jacket would be adequate IF you wore it under a shell like, say an eVent parka, etc. The body motion inside the shell would pump warm air to your arms anyway.

Also you'd be more comforable when exercising B/C the arms actually need to be less insulated than the core to prevent overheating.

But my idea of an insulated vest to be used when exercising would be a synthetic fill like Climashield, so it would transport sweat vapor fast and dry fast once I got to camp. Down is NOT for wearing when doing anything more than a stroll.

Eric,
again, I hardly ever need any insulating garments while I'm hiking. I am more interested in what would keep me the warmest when around camp.

-Sid

Usually the sleeves of a down jacket are sewn on. You could always undo that stitching and sew in a seperating zipper so that you could have the best of both world. I did that for Patagonia Down Sweater and it came out okay. You could also offset the zippers so that they start at the 4 or 8 o' clock position so that you could vent the arm pits. It will only add like 1-2 ounces max. Just get the thin small zippers.

Brett speaks great wisdom here. I once unstitched the arms of a synthetic jacket and sewed Velcro on them so I could use as Brett suggested. Worked great - until someone stole the arms!

BTW, my avatar shows my solution to in-camp warmth - an Eddie Bauer First AScent Down Sweater.

Edited by Danepacker on 02/02/2013 00:48:25 MST.

I think you guys are missing the point. My ultimate goal is not to be able to have both a vest and a jacket. I am fine with either one, I just want the warmer one. Adding sleeves with zippers would add a great deal of weight.

The whole point of me asking whether a vest or a jacket is warmer is because I want the warmest garment for the weight. This is why I said to assume they both have the same amount of down. By having the one with the most aggressive weight to warmth ratio, I save weight. Bringing sleeves along as some of you have suggested would defeat the purpose of me trying to save weight on my insulating top.

-Sid

Edited by Red_Fox on 11/26/2009 22:55:31 MST.

I've experimented with a vest versus a down jacket and I do know that my arms got uncomfortably cold. I was trying to get down to 32F comfortably while inactive. I wore a fleece shirt over my thin base layer, a Montbell Down Inner Vest and a rain jacket.

My logic was the same as somebody mentioned above; that as long as my torso was warm my extremities would be "warm enough". It turned out that my cold arms just made me feel cold throughout. I swapped out the vest for a Montbell Down Inner jacket and that combination was much more comfortable.

Since I'm only trying to stay warm for a few hours before jumping into my down bag, I could get away with either set of gear but the vest definitely makes it a less comfortable experience and the few ounces saved wasn't worth it to me. As always, with personal warmth questions, YMMV.

"In theory, focusing all the down on the torso area should keep you warmer, since that is where all your major organs are."

Your skin is a major organ, and 90%-95% of all heat is lost through it.

This might help factor into your super-formula for the great vest versus jacket debate. It seems you want to reach that optimal mix for core warmth, and be able to shed unneeded weight.

You have stated that you will be considering the heat while you are only doing light work (tending camp, making food) and not while hiking. You will not be fully at rest, however, so this should factor into our grand equation here.

That "light work" might get tricky, though? If you are a sweaty guy, or in a moist environment, this will increase heat loss.

Your question is also tricky in that your view of heat hasn't been defined as "I am comfortable at this temperature" or "I am just about to enter hypothermia." Are you looking to see what is the optimal down vest/jacket combination to keep you alive (garment weight considered)?

It seems people have been trying to answer your question with their own empirical knowledge, which without knowing more from you, seems the best answers you will get, for now.

I don't think people are missing the point, Sid. Rather, the point they're making is that your "ultimate" answer depends on weather conditions, etc.

In my experience, I'd much rather have the vest for warmth:weight. It does concentrate a lot more warmth on your torso. It also doesn't have all the fabric that's tied up in the arms. IIRC, when I make shells for vest vs. jacket I roughly double the shell weight between vest and jacket.

Well-designed vests won't have a significant amount of heat loss through the arm holes. I've found that wearing a down vest in conjunction w/a ~300g/m^2 wool mid and a ~150g/m^2 wool base keeps me warm into the 30s, especially if I toss a shell over it all. Of course that depends on the loft of the vest. My current favorite has a finished weight of 4.5 oz and used a little less than 3 oz of down IIRC.

The big down vest I made has kept me warm into single digits with a good wool sweater underneath, again a bit warmer/happier under a shell. But this is pushing it a bit more. In other words, if your frame of reference is "Will a jacket or vest, with equivalent mass of down, keep me the warmest at 0*F temps?" I would error toward the side of a jacket. If, however, you're looking for something for 3-season backpacking, a vest will keep you warmer for less weight.

Sid,

Comparing a jacket and vest, with the same weight of the same fill power, the vest will better protect your core temp. This assumes the vest seals well or is worn under a shell or windshirt that seals well.

This question is addressed by William F Forgey MD in his book, “Hypothermia”. He explains that the body’s vasoconstriction mechanism (to prevent heat loss) is activated much earlier and effectively from your body sensing your arms are cool. This results in the core temp not dropping as fast as it will with a jacket.

Edited by richard295 on 11/27/2009 09:11:51 MST.

Volaine,
I realize that skin is a major organ. Hence, I said "most" of the major organs are in the torso. Obviously most body heat has to go through the skin. However, out of all the major organs, I presume your skin would be your last priority as it can handle much lower temperatures than any other organ. I suppose I neglected to mention that I want to know what is best for backpacking, not a dangerous survival situation. Either way, I don't see how that variable would factor into my question, as the garment that is warmest for the weight would still be the best choice for either scenario. I do appreciate your input and everyone else's, I was only trying to make it clearer what my original question was.

Brad,
So it seems that a vest is best for 3 season backpacking, while a jacket would serve me better in the winter months. I suppose when temperatures get in the single digits, leaving any part of your body uninsulated becomes a risk.

Richard,
You make a good point. I should probably read that book myself to get a better understanding of the human body and heat loss.

-Sid

"Either way, I don't see how that variable would factor into my question, as the garment that is warmest for the weight would still be the best choice for either scenario."

My apologies. I think your avatar of a fox in the snow makes me see you tromping through some winter wonderland, in some crazy warmth-to-weight optimal outfit, like the scout from "Conan the Barbarian," hehe.



Best of luck in your hunt, Senor!