Will merino wool shrink after washing?

28 September 2020 | Marie Knowles

Merino is nature’s performance fiber, able to stretch and bounce back to shape. Writer Marie Knowles explains why icebreaker merino is durable and long-wearing and won’t shrink in the wash.

Our merino garments are easy-wear and easy-care. In fact, you can clean them in a washing machine without them shrinking. Merino fibers have an internal spring-like coil that holds the fiber’s shape. So, even our beautiful, soft knitwear is machine-washable. Just follow our simple care tips, below:

• Normal machine wash
  Use a normal warm or cool machine wash cycle with regular powder or liquid detergent. Separate light and darks as usual. Don’t use bleach, or softeners, which affect the natural performance properties of the merino fiber.
• Hang to dry
  With the exception of socks, hang your garment to dry on the line. You can tumble dry your socks, turned inside out, and on a low heat.
• Store folded
  Always clean your garments before storing – this helps prevent odors, stains and the build-up of dirt. For best results, store folded rather than hung.

Naturally stretchy

Merino wool is a naturally resilient and stretchy fiber, thanks to its internal spring-like structure. You can extend it 30% of its length without it breaking. And if you stretch it to 20% of its length it will bounce right back to the original. This means that when you wear our merino wool pieces, whether it’s socks out on the trail or our 100% merino base layer tops, they will keep their shape wear after wear.

Merino wool fibers are actually stretchier than nylon. Tests show that if you stretch nylon it breaks at 10% extension, versus merino’s 30%. Similarly, polyester fibers also stretch to a lesser extent than merino wool.

Naturally durable

The merino sheep is one of the world’s toughest breeds. It’s able to thrive in the extremes of its rugged mountain home because of the natural engineering of its fleece. If its wool fibers were not strong and durable for maximum protection, the sheep would not survive. That’s why we call merino nature’s performance fiber.

Naturally sustainable

Because merino fiber is made in the mountains, rather than a petrochemical laboratory, it’s naturally renewable and biodegradable (under certain conditions). Unlike synthetic microfibers, which are made from plastic, merino fibers don’t contribute to plastic microfiber pollution in the ocean. Synthetic microfibers are washed out of clothing – up to 700,000 in a full load of washing – and end up in our waterways and oceans. Wearing clothes with a high natural fiber content can help reduce the amount of synthetic microfibers that are released into the environment.

More care tips

Want to get the most out of your icebreaker? Here are some more tips:

• Avoid fabric softener
  It coats the merino fibers and reduces their natural ability to breathe and regulate moisture and temperature.
• Only dry clean if the label says so
  Some icebreaker merino garments are suitable for dry cleaning, but always check the label first.
• Limit ironing
  Merino bounces back into shape easily after washing, so you may find that you don’t need to iron your merino at all. Instead let any creases fall out naturally by laying your garment out flat, or hanging it over the back of a chair. However, if you do need to iron use a cool or specific wool setting and turn your garment inside out.
• Avoid bleach
  Chlorine destroys merino wool fibers, so please keep it away from your icebreaker.

You can find our full care guide here