Can I wash wool without it shrinking? Great question! Yes - we all want to know whether we can wash that 'DRY CLEAN ONLY' piece in our closet. Will it turn out ok, or will I ruin it even if I wash it by hand?
Here are some points to consider...
Woven fabric can still shrink, though it would not shrink as noticably as a knit or crochet piece. This is due to the fact that the yarn is spun with a tighter twist and is more compact. Also, wool suiting can be treated during finishing to help prevent shrinkage.
If you're wanting to wash wool suits - I would advise against that. The thing is that suit jackets generally have a lining. This lining, though it may be washable, would be pretty much impossible to iron if you washed it by hand.
There's no way you could get an iron into all the nooks and crannies of a jacket lining to make it look good. If you had a steamer maybe you could do it, but both the wool fabric and the lining might be susceptible to shrinkage by steam.
Not to mention having to press the creases in wool pants! My Dad used to be a Policeman and he would spend quite some time pressing the creases in his wool uniform pants - and he had a special tool for that! Oh boy! It's just not worth the risk - Dry Clean a wool suit or wool jacket!
Do you want to try to wash wool sweaters by hand? Check the fiber content. Does the sweater contain more than 50% wool or animal fiber? If so - it is still at risk of shrinking. Not so much as 100% wool, but there's still a risk.
If your sweater is a wool blended with an acetate or acrylic, then chances are it is less likely to shrink. BUT consider this too...if the acrylic content is high and the wool content low, you still can not wash the sweater in a hot wash.
Why? The reason this time is that acrylic loses its' "memory" when it is heated. What was a nice bulky, springy sweater after a hot wash would be all saggy and loose. It would most definitely be larger than before. Heat "kills" acrylic. So never tumble dry an acrylic yarn either, unless it says it's okay on the instructions! Learning how to wash wool is pretty complicated, eh?
I have successfully washed 20% - 25% wool sweaters on a cold "wool cycle" in the washing machine. A "wool cycle" does less agitation, to help prevent felting. However you must use a mild detergent or soap suitable for wool. The strong alkalies of regular detergents can seriously damage wool fibers.
This is how to wash wool sweaters by hand. Use lukewarm water only for all stages. Lukewarm feels just warm on your hands.
Hope this information helps you decide how to wash wool clothing. I have done my share of experimenting.
I have shrunk wool sweaters by disregarding the instructions and tossing them in the washer.
Now I know what to do and am very careful when I wash wool. Still, there may be a time when you might want to felt a wool sweater and try crafting something with it.
Check out my pages on felting - maybe you'd like to try it out!