Fleece shirt and vest are both identical in weight! Which one?!

The correct answer is: one of each.

I was shopping for down warmth for a cool summer, so I got one down vest and one down inner jacket. Together, they add up to about 12 ounces.

–B.G.–

If you want to minimize weight, ditch the fleece, get a synthetic or down vest

More warmth per ounce

Down is lighter but it's harder to keep it dry

The problem I have with down, is that the times I tend to get the coldest is in cold windy rain. Fleece will keep you warm when damp and it dries fast.

Down is a little bit of a gamble. Even with good DWR, it can get wet.

I always try to keep approximately twice the insulation on my torso as my arms and legs. So I usually have a vest over my inner layers in the cold.

There is some medical reason why you want to do that, but I won't get into it.

Okay, use a synthetic vest or jacket, still maybe 4 X more warmth per weight

Depends on what you're using it for!

Warmth while sitting around at rest stops or in camp: down or synthetic puffy jacket or vest

Thin insulation layer under wind shirt or rain jacket while actively hiking in cold weather, when base layer alone not warm enough–probably the thin fleece vest

The difference is that a puffy layer is going to be too warm (unless it's maybe around zero F or below) while you're actively moving. You don't want to expose puffy insulation, especially down, to any hint of perspiration! The fleece, on the other hand, absorbs very little moisture and dries faster.

If you're warm enough while actively moving in just a base layer and windshirt in the low temps you hike in, then forget the fleece layer; you're better off with a puffy for more warmth and less weight when you're inactive.

I have a lightweight fleece vest, but it goes with me only when I'll be hiking in temps at freezing or below, or if I expect considerable cold rain and need more warmth inside my rain jacket.

YMMV, of course!

If I am looking for warm insulative padding while I am wearing a backpack, then a fleece jacket or vest is perfect. If I am looking for a warm wrap while standing around in camp, then down is much better, because there won't be anything compressing it.

–B.G.–

pretty easy question, given they are the same weight (and same weight fabric)- I'd choose the shirt as it will give you a higher clo value for your insulation layer

if they are the same weight fabric, the vest must have other components (zippers, etc) that make it weigh as much as the shirt

I don't use fleece layers too much for three season use, but I live in a relatively dry clime- so down is my "go to" insulation layer

like Mary I do start using fleece (R1 and R2) when the temp starts dipping below the freezing mark- breathes well and dries quickly- which you really want in a garment(s) that your going to be moving in

Which Columbia vest is 9.8 oz?

Sorry guys. I should have included the fact that this is my insulation layer while actively moving in freezing rain. I have a puffy jacket for camp.

John – The vest is a Columbia Cathedral Peak that I found on clearance for $10 and I modified it by tearing out the two pockets and all of the zippers.

Since both garments are supposedly 100wt fleece (ie. same warmth), the shirt seems like the obvious selection. If the material is indeed the same, then the shirt will provide just as much torso insulation as the vest, plus it will insulate your arms. So the shirt should provide more overall warmth for the same weight.