32 Degrees Base Layers

There’s nothing at all wrong with inexpensive clothing, especially polyester in its many forms. Wear enough layers for the weather, and you’ll (usually) get many of the advantages of reasonably light weight, quick drying, good warmth-to-weight ratio, and moisture management that we all seek.

The common recommendations that you see (here and elsewhere) are typically splitting hairs about finding the absolute best garments at specific tasks. OR Echo is terrific for lightweight sun shirts, for example, although Walmart sells a t-shirt that is 80% as good(*) for 10% of the price. Short-sleeve-only, though. They do have a long-sleeve sun hoody made of nylon that is more similar to OR’s Astroman, which has higher SPF rating but doesn’t breathe quite as nicely.

The same goes for mid-layers. Alpha Direct and Teijin Octa (MH Airmesh) are the current state-of-the-art in warmth-to-weight ratio, but any fleece is usually pretty good, and is likely to be a better active insulator than most other materials.

The point is that the inexpensive stuff can be pretty good — certainly “good enough” for most tasks. Don’t get too wrapped up in the fancy name brands until (and unless) you feel like exploring them.

(*) Subjective opinion… not tested. :)

I picked up a few from Costco years ago. They’re okay. Super stretchy, but they tend to stretch out after awhile.

I picked up a few from Costco years ago. They’re okay. Super stretchy, but they tend to stretch out after awhile.

To be perfectly fair, the ex officio also stretched out after a while. They perhaps took longer to do so but then again they’re over four times the price. Also the 32° boxer briefs are 88% nylon and 12% spandex. I was specifically looking for nylon rather than polyester so these fit the bill quite nicely.

There are a couple varieties (one is a little more fleecy). I wear them almost everyday during the winter. I bring the bottoms backpacking (4.4oz). I will say they do not resist odor like more expensive garments.

I wear them all the time under my shorts.. To and from work. Also standing still outside at 5:30 am waiting 20 minutes for my train.  In the 40s and 50s.. Breezy wind chill.  I also wear them when hiking, In the fall NY weather or early spring time, again under my shorts. If it is really really cold out, then as a baselayer, under my sweat pants, R1 pants or whatever hiking pants I wear.  I sleep in them also when camping. They are so lightweight and packable. I posted a video recently, “What’s in my pack” and the very last item I pull out of my pack is a pair of 32 degree base layer. I get them from Costco and probably own about 6 pair because that’s how much I wear them and like them.

The 22% rayon content commonly found in these baselayers (not in the gray version though, only the black and white ones) helps to reduce odor some in these otherwise mostly synthetic (polyester and acrylic) garments.

I’m not certain why rayon has anti odor/anti microbial properties, but it does.  At least one study showed that only rayon out of polyester, cotton, wool, etc. completely prevented the growth of microbes on the fabric. Even wool doesn’t do this, but rather promotes the growth of non odor causing microbes (which ostensibly keeps the growth of the odor causing ones in check). 22% content is not enough to completely achieve this, but it does seem to reduce significantly above a 100% synthetic garment that is not treated to be antimicrobial.

Considering the price, especially with the sales at Costco, I consider them an excellent value, but yes, they do tend to stretch. I often wear them over a mesh baselayer as a “mid layer”, and under a windshirt/jacket for cool conditions.

Any thoughts on what would be better?

Define “better”?

The usual answer for ultralight warmth:weight ratio is Alpha Direct or Teijin Octa (like MH Airmesh). They have very high air permeability, so you need to wear a layer over them in wind, but opening that layer allows them to dump heat fantastically quickly. It’s an excellent combination with, say, a windshirt.

Natural fibers (wool, Merino, Alpaca) are fine if you like them, but Stephen Seeber’s test lab clearly demonstrates that the fiber doesn’t matter at all — it’s the weight of the fabric and how it is constructed and/or treated that dictates moisture-handling performance. In most real-world fabrics commonly sold, AD/Airmesh hold less moisture than most natural fabrics, although one super-thin merino tested slightly better in the lab. Natural fibers cost more and wear out faster, but don’t shed microplastics. Tradeoffs.

Mesh has a place, but AD/Airmesh are also mesh, and they do a similar job at similar weight, while adding extra insulation. I’ve experimented quite a bit with all three (AD/Airmesh/Brynje) and I like them all for different conditions. I usually advise people to get light AD60 or Airmesh first, because it is the most versatile.

(One use case for mesh that I would call “superior” is as a solo layer under a rain or wind jacket in moderate weather. This is the least warm layer you can wear, and vents heat faster than anything else when you open the jacket. It keeps the rain jacket off your skin which avoids the common clammy and cold feeling. I zip up in public, though.)

Polypropylene gets bonus points for being even more hydrophobic than treated polyester, so it doesn’t retain much moisture at all. Terramar, Helly Hansen Lifa, and older military surplus base layers (sometimes Rothco) may use polypropylene. Brynje’s “Super Thermo Mesh” and some versions of SealSkinz use Schoeller’s “Polycolon” polypropylene fabric. I would call it “different” rather than “better”, but that depends on what characteristics you like.

One note about Stephen Seeber’s testing. His methodology was testing static drying. Meaning, it doesn’t take into account things like polypropylene vs a highly water absorbent material like cotton, wool, silk, etc. in non static conditions like the following scenario.

With a 100% polypropylene fabric and garment, it only holds water in the interstice areas, which for static drying will dry about at the same rate as other materials. But what happens when you swing, ring, and/or fling out the water from the all PP garment vs a highly water absorbing material?  Especially when looking at PP fabric that isn’t made to wick?

You can swing/wring/fling water out of the interstice areas on an all PP garment quite quickly and fully in comparison to a highly water absorbent material. The surface energy is low enough, and the material so hydrophobic, that water readily separates from the surface. So the drying is sped up two fold.  The water leaves the interstice areas quickly with a little outside help, and the material itself doesn’t absorb, and thus doesn’t hold, moisture directly.

This is why when I wash any of my PP garments, after they have gone through the high spin cycle, they feel completely to almost completely dry to the touch, and quite light weight.  Doesn’t apply to my all natural/water absorbent clothing whether linen, cotton, wool, alpaca, etc.

With all that said, the 22% rayon in some of these 32 Degree shirts, doesn’t mean that it will take a long time to dry. If you just leave the shirt on and don’t try wring/swing/fling water out of it, it will dry about just about as fast as your average synthetic layer that is about the same thickness, structure, and air porosity.

(The above is why I always bring a backup non wicking PP baselayer, because being 34% less dense than polyester, and with it’s ability to dry so fast with a little outside help, and having a lower thermal conductivity than polyester and even wool, it’s a great, lightweight backup.  Especially my baselayers that are made of hollow core polypropylene fibers. Super light weight and relatively warm for the weight. Now if they were only treated to be lower odor, they would be nearly perfect).