Will cashmere felt?

We have all heard the horror stories: a luxurious cashmere sweater goes into the washing machine, and it comes out looking like it belongs to a toddler.

The short answer is yes, cashmere felts very easily. In fact, it felts even more readily than sheep’s wool.

While felting is usually seen as a laundry disaster, it is actually a natural property of the fiber that—when understood—explains exactly why cashmere is so warm and delicate. Here is what is happening on a microscopic level.

1. Why Does Cashmere Felt? (The Mechanics)

Cashmere fibers, like human hair, are covered in microscopic scales.

• The Trigger: When you combine moisture, heat, and agitation (like the tumbling of a washing machine), these scales open up.

• The Locking: As the fibers rub against each other, the open scales act like Velcro, interlocking tightly.

• The Result: The fibers pull closer together, eliminating the air gaps between them. The fabric becomes thicker, denser, and significantly smaller. This process is irreversible.

2. Accidental Felting: The Laundry Disaster

Most felting happens by accident. To a customer, it looks like “shrinkage,” but it is actually a change in the fabric’s structure.

• Hot Water: Opens the scales.

• Spin Cycle: Forces the scales to lock together.

• The Fix? There isn’t one. Once cashmere has felted, the fibers are fused. You can sometimes stretch it back slightly with conditioner, but it will never regain its original drape or softness.

3. Intentional Felting: “Boiled Cashmere”

Interestingly, some designers want this to happen. You might see “Boiled Cashmere” or “Felted Cashmere” on high-end labels.

• The Technique: Factories intentionally wash the knitwear at high temperatures with specific agitation.

• The Benefit: This creates a fabric that is denser, more wind-resistant, and more durable than regular knitwear. It looks more like a structured jacket than a slouchy sweater. However, this must be done with extreme precision to control the size.

4. How to Prevent Felting

If you want to keep your cashmere soft and lofty (and adult-sized), you must avoid the triggers:

1. Cold Water Only: Keep the water below 30°C (86°F) to keep the fiber scales closed.

2. No Agitation: Never wring, twist, or scrub the fabric. Squeeze the suds through gently.

3. No Tumble Dry: The heat and tumbling motion are the fastest way to felt a sweater. Always lay flat to dry.

The Verdict

Cashmere’s ability to felt is a sign of its natural origin. While it can be a disaster in the laundry room, knowing how to handle it is the key to making your investment last a lifetime.

Protect your investment: Use our dedicated Cashmere Shampoo for a safe, felt-free wash.