Insulation value of different types of wool

Hello,
I’m wondering how the insulation values of different types of wool compare to one another? As in wool batting vs felted wool vs knit or woven materials? I just made myself a parka liner from a felted wool blanket (Swiss link) and it’s working well. I have a young friend who loves to mush dogs but is always cold and was thinking of making something similar for her but I’d love it if it could be warmer and lighter weight. I got to thinking that wool batting may give a better insulation value for its weight, but I really don’t know. Does anyone have insight into how different wool preparations compare in insulation value? Also if anyone has any other suggestions for a light weight natural insulation I’m all ears. Down is obviously fantastic but I’m a little bit bewildered by how to construct a down garment at home… but maybe I just need to research that more.

Thanks for your help!

Eloise

wool insulation has two main things.
1. the structure (aka, air trapped in the individual fibre core) of the fibre itself
2. the air between the fibres.

For 2, this is why squishy wool (has more crimp) makes warmer sweaters.

Then there is how the insulation settles over time.  Felt or fabric would probably settle less where as loose fibre would settle most.  Carded would be somewhere between.

With this knowledge, we can choose the fibre - squishy/down/high crimp for more insulation, then choose the style of how it's held together to match our needs.  

Unfortunately, this is where things get complicated as the felting or fabric structure dramatically influences how much air is trapped in the cloth.  But tradition tells us that a woolen spun, down breed wool, knitted in a looser gage is one of the most insulating sweaters.  However, it doesn't block the wind, so it's often combined with a worsted spun, tightly woven, highly fulled (like felting but for cloth) outer layer.  

r ranson wrote:wool insulation has two main things.
1. the structure (aka, air trapped in the individual fibre core) of the fibre itself
2. the air between the fibres.

For 2, this is why squishy wool (has more crimp) makes warmer sweaters.

Then there is how the insulation settles over time.  Felt or fabric would probably settle less where as loose fibre would settle most.  Carded would be somewhere between.

With this knowledge, we can choose the fibre - squishy/down/high crimp for more insulation, then choose the style of how it's held together to match our needs.  

Unfortunately, this is where things get complicated as the felting or fabric structure dramatically influences how much air is trapped in the cloth.  But tradition tells us that a woolen spun, down breed wool, knitted in a looser gage is one of the most insulating sweaters.  However, it doesn't block the wind, so it's often combined with a worsted spun, tightly woven, highly fulled (like felting but for cloth) outer layer.  

Thanks for taking time to respond r ranson! I think I’m following what you are saying, but it seems I don’t have the basic knowledge of fiberous things to grasp it fully. If you’re willing, I’d love to have a few things clarified.

1. You said squishy wool has more crimp. Could you define crimp? Is that descriptive of each fiber or of how the fibers sit together (air space between)? Is it related to the species the wool comes from or the processing method or both?

2. You said, “ tradition tells us that a woolen spun, down breed wool, knitted in a looser gage is one of the most insulating sweaters.” What is woolen spun? Down breed wool?

Thanks so much for your time!

I'll try to remember to go out in the morning and get a photo of one of the hoggets to illustrate crimp "on the hoof" for you. She's got a truly gorgeous fleece.

Crimp is one of the main ways they categorized wool.  More crimp means each fibre has more squiggly.   Like curly hair vs wavy in humans.

Down is a category of breeds of sheep from the downs of England.  It is what most modern sheep come from as the wool works well with industrial machines.  They are known for high crimp and consistent wool.  They also make an excellent meat sheep and thus replaced a lot of older breeds during the English industrial revolution.



Woolen spun is a way of making yarn that has a lot of air trapped in the yarn and is quite fluffy.  The opposite would be worsted spun which creates a smooth, dense yarn and fabric that doesn't allow much air through.  Most yarns are somewhere between the two as full woolen and full worsted take a lot of skill and labour to produce.

A Cowichan sweater is a good example of a higly insulated sweater that takes advantage of wool and yarn.  Although the kind of sheep has changed over the 20th century, it's still an amazing sweater.


source

Whereas a fisherman sweater needs to keep out the wind so would be tightly knit and often have smoother yarn.

Here is what crimp looks like out in the paddock. Test subject J loves having her photo taken.



16-month-old hogget (young ewe) showing spiral twists at tips of fleece.



Closeup showing how the spiral strands form a wavy pattern...the crimp. Wool with a strong crimp has more natural loft than straighter fleeces.