Non insulated back when carrying a backpack?

I never ordered such a garment.  They sound appealing for UL pursuits, but I’ll be cold in camp with my pack off.

If I need insulation, then overheating my back has never been a huge issue. I compensate by opening my front zipper, and let my body shift bloodflow around to suit the conditions.

Overheated back is more of an issue (for me) in warmer weather. It isn’t sweat that bothers me, it’s the inability to cool my back when it is squished against waterproof pack fabric. I prefer some kind of back ventilation, although it doesn’t need to be complete. For example, a close fitting belt on my lumbar region (and maybe around the shoulder blades) is OK, as long as air can move a bit around the rest of my back. This doesn’t require the pack to be far off of my back… just not pressing against it.

Note that a shirt will always be pressed against my back, even by a trampoline harness. It’s the ability for that layer to cool (by evaporation) that is important.

Hi,

I think you’re right. Initially I thought that no insulation on the back would prevent sweating and provides better “breathability” but in reality the pack will block any air. So even if the back panel is mesh I’m thinking it won’t make a difference. I found the same concept here https://raideresearch.com/products/mens-tourtech-hybrid-hoody but no actual reviews or numbers.

Agree with Todd and Bill.

For a backpacking mid layer it makes sense to keep the full insulation in the back, for use in camp/with pack off.

For a base layer or special use mid layers it can make sense to have some fabric mapping to reduce sweat build up. I have a Norrøna Fjørå equaliser top that I like for this reason (although the fabric on the back is so nice, I may have preferred to have it on the whole piece :)  )

Some times the way a brand choose to map their materials makes me scratch my head.
I was just looking at the Outdoor Vitals Pursuit hoody (as I still have some credit there I want to close out). It uses a combination of stretchy grid fleece and a Primaloft evolve backed woven nylon. As you typically see, there is grid fleece in the sides and arm pits, but for some reason they’ve put grid fleece on the lower half of the front and primaloft evolve with the wind resistant outer on the back. Just seems a bit backwards to me. Personally I’d much rather want a fully protected front, as the back will be protected by a backpack most of the time anyway.

Timmermade has an extra snap on some of their insulated jackets so that you can wear it backwards with a pack. Basically put sleeves on, and cinch the neck (and I think also with another at the bottom, at the back of your waist) around with the snap at the back. I don’t have one and haven’t tried it but seems like a relatively simple easy solution when hiking in relatively non-technical conditions.

I’ve made a bib  from a 30″x17″ piece of Alpha Direct 60 that weighs 1 oz. Edges are unfinished but fraying is minimal. I wear it under a wind shirt or even under a base layer for an extra warmth boost. This is often  my only mid layer during fair weather backpacking/hiking. The best thing is that I can put it on/off without taking off a pack.

Wow I didn’t think of that! That’s really smart. So you some how tie it on your back? Or just tug it in your pants? I’m thinking this kind of setup could suit me well for ski touring where my pack is on my back 99% of the time.

Similarly, I carry a barber’s cape during shoulder season variable conditions. It’s just a big bib: quicker on/off than a full windbreaker. Mostly I don’t find a need to tie it down. It just drapes, like a poncho. It has a cord tie. I added sewing clips so that I can clip it to my pack when necessary.

I have that Yamatomichi vest and don’t find it very useful.  The weight is similar to an AD60 hoodie but it’s not as warm and not as flexible.  AD120 in general is not very useful in my experience, a lot heavier and only a little bit warmer when layered.

I have something like the bib above, it’s worth its weight since it’s less than an ounce.

I just tuck the bib into my pants and drape the back over my shoulders. AD fabric is a little floppy but it works good enough.

I have a Sporthill Nordic ski top with zoned fabrics, bought ~25 years ago and used for ages skiing and snowshoeing.  The back is extremely breathable by the vadar test and lighter than the rest of the garment, while the front is wind blocking.

The devil is in the construction details.  The back is still thick enough that it holds a ton of sweat when under my pack, which then freezes on the inside when conditions get cold enough.   Even with a trampoline back which 2 of my packs have.

The best winter sweat management I’ve found under a pack after trying many combos is a mesh base layer like Brynje.  Even if the mid layer gets moist, its off your skin and that makes a big difference in perceived comfort and warmth.  At least for me.