A Guide To Wool Fabric: Different Types, How It's Made & More

Mar 14, 2024

Looking to clean up your wardrobe and adopt a slow fashion mentality? Wool can be a great material to welcome into your eco-closet. Here's what you need to know about the different types of wool, how they're made, and how to spot a sustainable, durable wool garment.

Wool is a natural fabric made from the hair of an animal. While wool is most often associated with sheep, it can also come from alpacas, llamas, goats, camels, and rabbits. Because of its breathability, longevity, and versatility, it's used to make clothing, upholstery, blankets, carpet, and more.

Turning wool into fabric takes a few steps. And according to a professor at the Fashion Institute of Technology and the designer of Born Again Vintage Bridgett Artise, the raising and processing (first and last) steps are what you really want to pay attention to when shopping for a sustainable garment. Here's how it all works:

It starts with shearing (or cutting) the coat of a wool animal. This usually happens about once a year.

While PETA claims that shearing hurts the animal, this is an extreme outcome and generally happens if the animal isn't given the proper time to recoup its fleece before the next shearing. Meaning, the animal is only harmed if the farm or shearer in question cares more about profit and the amount of wool than the animal itself.

Otherwise, shearing is pain-free for the animal and necessary for maintaining the health of the flock. When sheep that are bred for wool don't get sheared, their hair can get too long and start to trap debris, making the animal prone to illness.

After the animal has been shorn, the wool is sorted to remove the unusable pieces of the fleece. Once those waste pieces are repurposed or put to the side, the rest of the wool is scoured to remove the natural lipid lanolin and dirt from the fibers.

Traditionally, scouring is done with warm water, but some wool producers opt for using chemical additives to speed up the process.

Then, the wool most often meets its first machine—the picker. The picker separates the fibers and combs out larger debris still entangled in the fleece.

Next, the wool is "carded" to make sure all of its fibers are straight, elongated, and lying in the same direction. This can be done by hand or with a carding machine specifically designed for the task. Once carded, you're left with what's known as roving—wool that's ready to be spun into yarn.

From there, the roving is spun into yarn in one of two ways: worsted or woolen. The worsted system results in soft and dense wool, while the woolen system results in irregular and light wool.

After the wool yarn is created, the wool is ready to weave or knit into fabrics!

Chemical treatments, like a chlorine wash to prevent felting, can be applied before or after the final garment is produced.

Unfortunately, treating wool with chlorine involves using tons of water and electricity. The process also creates water runoff with concentrated amounts of adsorbable organohalogens (AOX) toxins, making it potentially harmful to the environment.

Chlorine-treated wool is also known as washable wool. To avoid contributing to this environmentally taxing process, look for pure untreated wool, chlorine-free wool, or AOX-free wool.

There are many varieties of wool. Here are some of the popular types you'll likely find on the rack:

Wool is an inherently durable fabric. With the right care, it can last you forever. It’s also super versatile, and there are so many types and blends out there to choose from.

Overall, Artise considers wool a very sustainable fabric. She especially appreciates the fact that it's a natural material that is compostable as long as it's not chemically treated.

On the flip side, wool is a tad temperamental and can felt or shrink if it isn't properly washed. (Check out a wool care guide here.) Some people may also find certain wool fabrics uncomfortable or itchy.

And though the material is sustainable by nature, it can be treated with toxic chemicals.

Take good care of your wool garments and they should last you a lifetime. Since wool is so durable, Artise says it's a great material to thrift, borrow, or buy secondhand.

When you do want to buy new wool, consider it an investment piece. Take the time to do the research before deciding on the right choice for you.

"If you're interested or happen to like a particular brand, you need to take the time to find out where their wool is sourced," starts Artise.

Peek around a brand's website to see how their animals were raised and how often they were shorn. Avoid companies that have been accused of mulesing, aka cutting crescent-shaped pieces of skin from the rear of the animal to prevent flies (and maggots) from creeping into the folds of its wool. It's painful and harms the overall well-being of the animal.

On the processing side, go with pure wool that has not been chlorine-treated (AOX-free). If you can't find information about a company's wool online, Artise recommends writing in to ask about it.

These third-party certifications verify wool that has been created with the well-being of the animal and the environment in mind:

Wool is environmentally friendly from the jump—but if you're looking for a wool staple for your wardrobe, get ready to play detective. "We all have a specific role in regard to how we can contribute more to the sustainability of anything," Artise tells mbg. That means that in the end, that cozy wool sweater will be worth the little extra legwork.

Alex Shea is a storyteller and generational healing life coach with words in Byrdie, Verywell Mind, HuffPost, Shape, and more. Outside of publications, Alex writes stories that touch on, and sometimes intertwine, themes of grief and magic.

With a unique view on life, she taps into her own experiences to guide folks to live life for themselves, empowering them to explore their inner wild and find their own way in adulthood. Her weekly newsletter is a tiny way she furthers her mission to hold space for the unfathomable, romantic, and messy parts of life that make it that much more beautiful.