Field Test of Montbell Down Inner Jacket and Fleece…

Perhaps your body temperature is coldest during the second half of the night. If that is true, your test didn't compare apples to apples.

Well as they say one test is worth a thousand hypothesis. Thanks for taking one for the team.
Im not surprised at your result. I own a few fleece down clothing items.
If I'm reading your results correctly and the jackets are approximately equal in warmth while stationary, the 6.9 oz Montbell tested out at almost twice the warmth per unit weight of the 11.6 oz fleece. That is why many of us carry these Montbell down jackets. If there is a wind or you are active, the nylon-shelled down will prove even warmer per unit weight, IME.

Per MontBell's catalog, the UL down jacket is supposed to be "warmer than most heavy fleece jackets"! This means not just warmer per unit of weight as Brett mentioned above, but warmer in the absolute sense! And yet, Ryan wrote that his down jacket felt less warm than his light fleece jacket!

Brian wrote that both set up felt slightly chilly, but still generally OK enough to fall asleep. I am thinking that perhaps Brian took a while to fall asleep in the first half of the night when he wore the MontBell — and / or slept fitfully — after all, it wasn't toasty warm — and thus he was quite aware of the surrounding coolness.

By the time Brian started testing the fleece set up at 3am, he was probably much more tired — and so he fell asleep more quickly and slept more soundly (the fleece set up wasn't toasty, but it was good enough overall). Thus, Brian probably felt the coolness of the fleece much less. In other words, having fallen into a quicker and deeper sleep, he felt pretty OK. Just a guess, of course.

then i would have to say that based on my experience the mb down inner is much warmer than most of the fleece jackets i own (and now only use for snowboarding or cross country skiing). plus, as brett says, so much lighter and compactable.

If you want warmth and are willing/need to carry the extra ounces, check the mb alpine down jacket. got that last season for winter treks… oh so warm.

I tried both the fleece and the jacket out again a couple nights ago. I didn't sleep in them, and I was much less "scientific" this time. I just tried them on and stood around outside. It was about 27 degrees outside, and there was definitely a noticable difference.

The colder it gets the easier it is to tell a difference between two clothing systems, and I think my previous experiment (with my sleeping bag) might not have been cold enough for me to tell the difference. (I don't know if I'm making any sense).

>>> If you want warmth and are willing/need to carry the extra ounces, check the mb alpine down jacket. got that last season for winter treks… oh so warm.

You said it Dylan – I just got one… so nice and puffy.

yeah, isn't the alpine nice? it makes the ul inner seem even lighter.

i also have to ask, is your avatar pic taken on the na pali coast? looks a lot like it.

Sure is! It was an awesome hike.

we only day hiked out a few miles on the trail. i've wanted to go back and do a few nights out there.

Hello,
my fiance and I are thinking of going out and doing a multiday hike at Na Pali for our honeymoon next November. Does anyone know where I could find solid info on the hikes and/or island conditions? Thanks

There should be a difference in relative warmth of the two pieces depending on how they're used. When the wearer is laying in a sleeping bag the down will be compressed underneath the wearer, so the piece will lose much of its insulating ability. Fleece, however, doesn't compress that much, nice when you're in a sleeping bag, not so nice in a stuff sack. However, when in camp the relative results might be quite different.

As a second experiment, try unzipping the down jacket and laying it over you like a quilt, rather than wearing it.

Fleece needs at least an outer layer like a windshirt to be more equivalent with down as the down has two wind blocking layers, plus the loft. Fleece is warm and comfortable against the skin and less binding for sleep. Down can compress and pack better than fleece. Fleece is relatively cheap compared to down, although some manufacturers seem to think it is gold. Fleece is much easier to wash and maintain than down.

The most important differences: fleece is superior in moderate cold and wet environments. Down is superior in higher loft and extreme dry cold, where the comparison shifts to polyester fiber fills like Primaloft, Delta, and 3D and the superior wet performance remains. Down delivers more loft for weight and packs better.