What Is Superwash Wool?
If you've ever shopped for yarn, you've probably noticed the terms "superwash" and "non-superwash" on yarn labels. While both begin as natural wool, they behave quite differently due to the way they are processed.
Understanding what superwash wool is—and how it compares to non-superwash wool—will help you choose the right yarn for your next project.
What Is Superwash Wool?
Superwash wool is wool that has been specially treated to make it machine washable and more resistant to shrinking and felting.
Naturally, wool fibres are covered in tiny overlapping scales. When exposed to heat, moisture, and agitation, these scales interlock, causing the fabric to felt and shrink.
The superwash process modifies or removes these scales so they can no longer lock together, allowing the finished yarn to be washed in a machine without felting under normal care conditions.
How Is Superwash Wool Made?
There are two common methods used to create superwash wool:
Polymer Coating
The most common process removes or smooths the outer scales before applying a very fine polymer coating around each fibre. This creates a smooth surface that resists felting.
Scale Modification
Some newer treatments use alternative processes to modify the fibre scales while reducing the amount of synthetic coating required. These methods are designed to improve the environmental footprint of superwash processing.
Benefits of Superwash Wool
Superwash wool offers several practical advantages:
- Machine washable for easier care
- Resistant to shrinking and felting
- Soft against the skin
- Bright, vibrant dye colours
- Excellent for baby garments and everyday wear
- Easy to care for in busy households
Because of its convenience, superwash wool is popular for garments that will be washed frequently.
Things to Consider
While superwash wool is incredibly practical, it behaves differently from untreated wool.
Some knitters notice that superwash yarn:
- Has less "grip" while knitting
- Can feel smoother or silkier
- May stretch or grow slightly after washing
- Doesn't bloom or full in the same way as non-superwash wool
For projects that rely on structure—such as cables or colourwork—it's worth checking your gauge after washing.
What Is Non-Superwash Wool?
Non-superwash wool is wool in its more natural state. The fibre scales remain intact, giving it characteristics many knitters love.
Non-superwash wool generally offers:
- Better elasticity and memory
- Greater stitch definition
- More natural texture
- Better insulation
- The ability to lightly felt or bloom after washing
Many traditional knitters appreciate the authentic feel and performance of untreated wool.
Which Should You Choose?
The best choice depends on your project.
Choose superwash wool if you're making:
- Baby garments
- Children's clothing
- Everyday sweaters
- Socks
- Gifts that require easy care
Choose non-superwash wool if you're making:
- Traditional sweaters
- Colourwork garments
- Felted projects
- Heritage knitting
- Projects where stitch definition and structure are important
There's No Right or Wrong Choice
Both superwash and non-superwash wool have their place in the fibre world. Superwash offers convenience and easy care, while non-superwash celebrates the natural beauty and performance of wool.
Understanding the differences allows you to choose the yarn that best suits your project, lifestyle, and personal knitting preferences.