merino vs. synthetics, the secret is vapor transport?

Makes sense to me. Another point about wool is that it absorbs moisture and holds it within its fibers, unlike synthetics whose fibers don't absorb much moisture to speak of.

It's just marketing.

Synthetics transport moisture better, that's why there is more of a "flash cooling" effect. (The wool holds the moisture a little longer). Whether this is better for moisture "management" depends on whether you'd like the clothing to dry as quickly as possible, or would like to be warmer while it's drying…

Also, your body sweats liquid. It doesn't become vapor unless a breeze hits it, or the heat from the air evaporates it. And vapor is just smaller pieces of liquid that are too small to condense into a droplet anyway…

I notice the following differences between wool & synthetic:
– Synthetic transports moisture faster – sometimes too fast, resulting in an uncomfortable "flash-cooling" effect that works like a refrigerator.
– Wool base layers feel warmer when you stop hiking and they are a little damp from perspiration, but take longer to actually dry (important if you want to sleep in them).
– The breezier feeling clothing is the one with the looser weave. The material doesn't seem to make any difference.
– The most sun blocking clothing is the thicker one. The material doesn't seem to make any difference.
– Synthetics are a whole lot stronger in thin fabric than wool – especially when wet. ie: easy to stick your finger through or accidently rip when pulling a handful.
– Wool smells better after several days. Antibacterial treatments for synthetics handle about 75% of this problem – at least before the coatings (etc) wash out.

Hi Brett!
At first blush I'd have to agree with John: It's just marketing. But then again maybe not. When at rest such as sitting in my chair typing this or asleep in my sleeping bag there is a form of perspiration that is not liquid called insensible perspiration, and throughout the day the body is losing moisture, even when we're not working. Ideal comfort conditions for the body would be an average 75 degrees ambient air temperature and surprisingly moist skin – 70 to 95% humidity! When we feel comfortable we equate that with dry skin, but that's because the high humidity is a body enveloping layer only about 1/4" thick from insensible perspiration, which keeps the skin moist. It's like an invisible suit of armor! Truely dry skin would be flaky and cracking.

And now that I think about it, whenever I've been at rest – say, spending a couple hours reading a book – and wearing my merino, I have indeed felt cool despite being in a warm room, not at all like being all bundled up in wool. So maybe there is something to their claim.
Happy trails!

Please forgive the following random thoughts and lack of understanding:

All synthetics are not equal. Far from it. How does this come into play? Some syn stuff I've had was horribly hot. Some newer stuff (UA Heatgear) will give you the chills.

Most synthetics are petroleum based, which without treatment would be hydrophobic, right? So what is the moisture transport mechanism, diffusion? Direct vapor emission?

I seem to recall pics of a couple BPL staffers wearing red and blue "clown shirts" to test wool versus synthetic. As I recall, the shirts were made by joining halves of each type. Maybe some good info there?

I commonly use wool in the summer, and synthetic in the winter. Seem backwards? Well maybe. But the wool is very fine merino, and my winter sythetic is UA Coldgear.

Somebody please help it all make sense~!

Just a smidgen off-topic (or maybe not), but I work with one of those perenially cold type people who absolutely loathes any outdoor activity, and her idea of dressing for the weather means putting on a GoreTex jacket while holding an unbrella while waiting to catch the bus.

She arrives at work and the first thing she does each day is turn the thermostat up from 22 celcius to 26 celcius claiming she's cold. At this stage she has removed her GoreTex jacket to reveal her single layer of 180gms knit wool IceBreaker top. She is a notoriuos fashion victim, and not only does she "know" that Ice Breaker garments are worn by sailing crews navigating the Antarctic oceans (because 'wool is warmer than cotton'), but she also can't help noticing that her particiular garment is labelled "Ultrafine" merino. When I try to suggest that perhaps, instead of baking the rest of us, she wears warmer clothes, she always replies along the lines of "But it's IceBreaker…it keeps you warmer than any other fabric".

I bring this up because, once upon a time, I came across a good study showing that in dry conditions with no wind that thickness of fabric is the mosty important factor in keeping warm. To me this is a No-Brainer, but this woman is a scientist, so I have been looking for scientific references to help me pursuede her to get herself a nice thick cotton or fleece pullover, or even a down jacket, to wear at work. At the evry least, fi she has to wear IceBreaker, to go for the thickest stuff available. Do any of you know where I might find some convincing material? I'm sweltering as I write this!

You need to find some information on clo and tog clothing insulation measurements. Here's one reference:

http://www.engineeringtoolbox.com/clo-clothing-thermal-insulation-d_732.html

Allison
I worked in offices where people insist in having 26 degree in winter and 18 in summer. No amount of reasoning is going to change that mentality.
Scientists ?
It took Stephen Hawking 30 years to admit that he was wrong about his theory
on black holes. Not that the new version is necessarily correct…
Franco
Good luck anyway

Franco

Of course I know you're right ;)

I still can't convince the folks I work with that trying to find genes for drug response in a complex mental disorder, where the drug has around 50% placebo response, and trying to find these genes in outbred rats that don't even have the mental disorder and are certainly not prone to placebo response…is a very bad idea from a scientific standpoint. Again, I would have thought it was a no-brainer, but I guess it's gonna take a lot more than some CLO chart to change the cloudy thinking!

But I would like to find those studies for my own future reference.

My biggest beef with the lizard metabolism is that the cold person can always put on more clothes…I can't legally take any more off to maintain my temperature, so I would vote that the warmest person gets to dictate the work thermostat. But of course I'm biased. I would have it at 18 all year round.

Allison, tell her that you read on the Icebreaker website that their ultrafine merino is intended as a base layer to be worn underneath something. That means she's wearing her underwear on the outside! Could be she adores Madonna?