Why Does Wool Keep You Warm When Wet?

[Roger Norris]

I found this on line....thought it was interesting:


Wet Wool
Lik­e we said, wool can soak up a lot of moisture without feeling wet. This makes wool a hygroscopic insulator. The crimp in the wool fiber forces each strand to butt against each other, as opposed to lining up side by side or laying down flat together. This keeps the tiny air pockets intact, acting as little insulators -- the key to being able to keep you both warm and cool. Air has the ability to move heat by convection -- in other words, by moving and circulating. Through convection, air can transport heat from one place to another. When air is contained in very small pockets, it can't circulate easily, so heat is retained. Same goes for cold. Think Styrofoam cooler -- the Styrofoam's tiny pockets of air act as an insulator for heat or cold (depending on what's inside the cooler). The same concept goes for wool.
There's also some science at work here. Wool fibers are made up of cortical cells, and these cells are wrapped in cuticle. This scaly outer layer is then covered by yet another layer, the epicuticle -- a filmy skin that helps to repel moisture. What's more, the epicuticle also helps out in high humidity because it has tiny pores that draw in the moisture vapor to the center of the fiber where it's absorbed by a chemical process. The hydrogen bond of water, H2O, is actually broken, creating a chemical reaction with the wool fiber molecules to generate heat when it has taken on a lot of moisture. But because the air pockets allow moisture to evaporate from your skin, you won't overheat when you sweat.
The combination of the fiber's natural crimp and the chemical and physical processes that take place when wool meets moisture make it the best all-season natural insulator on Earth. It actually absorbs water from both your skin and the atmosphere around you to create a dry and warm environment where it counts -- against your body. So the next time you pass a herd of sheep standing around in the pouring rain looking dopey, remember the complexity of their protective coat.
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[Terry Green]

[kadbow]

Hmmm, that is what I thought.

[Roger Norris]

Nah Terry....that aint wool...wool is plaid    :D  

Thats a pretty cool diagram, thanks.

[Terry Green]

Wool can also gain up to 18% of its weight in moisture without feeling wet.

[Lamey]

cuz its the way God made it  

[Roger Norris]

I have a thick Filson Double Mackinaw, that I have worn for years....in everything from a pouring rain to below 0 temps.....the dang stuff works. I'm one of those lucky folks who has no itch from wool. I still have some Army issue wool longjohns (I do believe they are some kind of blend)that were given to me by Uncle Sam in 1981. They are a bit tighter, but they still work.

[Steve O]

I used to have a Filson Double Mackinaw that would go on to take the dog for a walk EVERY night during the long MI winters.  The collar irritated my face when up, so I had some silk sewn over it.  Nice.

[Phrogdrvr]

Interesting read.  Always knew it worked, never bothered to figure out why.  I'm another one of the lucky people who don't get the wool itch.  A dermatologist once told me that people who aren't allergic to poison ivy, don't get the wool itch.  True in my case.

Thanks for the info Roger.

Tom

[maxwell]

Nice post, Filson wool garments have worked for me for years.

[Terry Green]

Originally posted by Lamey:
cuz its the way God made it    

Amen

[Terry Green]

Also...if you ever wear thin wool socks in the summer...

you will throw your clammy cotton socks away.    

[Roger Norris]

Originally posted by Terry Green:
Also...if you ever wear thin wool socks in the summer...

you will throw your clammy cotton socks away.      

Absolutely. I wore thin quality wool socks this passed September in Wyoming. Daytime temps of near 80, walking lots. My feet were very comfortable.

[NoCams]

Lamey said it........    

Try as he may man cannot make a fiber better than wool or a insulator better than a down feather......  

[JDunlap]

I started wearing my wool socks to work in the oilfield at the end of summer and I agree, they are cooler than cotton.

[Terry Green]

Originally posted by NoCams:
Lamey said it........    

Try as he may man cannot make a fiber better than wool or a insulator better than a down feather......    

Or carpet...if its wool from New Zealand.

[Ric O'Shay]

"This", as Brother Mudd would say, "is a way cool thread!"      

[Terry Green]

Both...wool keeps sheep cool in the summer.    

[Biathlonman]

I get posion ivy something awful and wool does itch me, even the good high dollar merino.  I still wear it as a base layer cause I can't find anything better.

[BowDiddle]

Not only are the thin wool socks cooler in the summer, but they will also reduce the chance for blisters.