Why We Don't Superwash Our Merino

The short answer

Unlike most big merino sock brands, we don't superwash our merino.

Here's why.

Superwash wrecks the very thing that makes merino worth wearing: the natural water-repelling outer layer on every fiber. That layer is what keeps your skin drier, cuts friction and helps stop blisters before they start.

We make socks for hikers, trail runners and ultra runners. People who need their feet to hold up on the big efforts. Performance isn't negotiable and should not be washed away.

Many merino socks out there are superwashed. Most people have no idea. Here's what's really going on and why I feel after being superwashed, it isn’t true merino anymore.

What superwash actually is

Under a microscope, a wool fiber looks a bit like a pine cone, covered in tiny overlapping scales.

Those scales are part of what makes wool so good. Yes, the scaled outer surface can cause some shrinkage and felting, particularly when the socks are washed with a lot of agitation.

And that is what led the big mills and sock companies to develop and choose superwash. They chose easy-care, over fiber performance.

Superwash is the industry's shortcut. It's a two-step process:

A chlorine bath that eats away at the scales (the outer surface of the merino fiber)
A plastic resin (a polyamide called Hercosett) bonded over the wool fibers to smooth out what's left.

Why?

For ease of washing. Wool you can chuck in the wash like a synthetic… but it's not really merino anymore imo. Superwash also softens the feel of the fiber, which lets mills get away with coarser, cheaper wool. We don't need that trick, because we knit with superfine merino.

You'll also see it described under other names with similar, varying processes, such as Total Easy Care (TEC). TEC is a machine-washable standard, usually met with the same chlorine-and-resin treatment.

It's the industry norm. Most of the big merino sock brands use it.

Why we skip it

The outer surface is everything.
Untreated merino has a clever two-part design. The outside of each fiber naturally repels liquid water, while the inside soaks up sweat vapour from your skin. Hydrophobic outer, hydrophilic inner.

That's what keeps your skin drier and your feet comfortable, mile after mile. Drier skin means less friction. Less friction means fewer blisters and irritated, soggy skin after a full day of hiking.

Superwash strips that outer layer away, and with it, what makes merino great.

The science backs it up. A 2024 study by AgResearch here in New Zealand left superwashed and untreated wool in seawater for 90 days. The superwashed wool broke down more than three times as much (26.9% vs 8.1%).

In short, in wet conditions, that stripped surface left the superwashed wool far more open to breakdown

The researchers' explanation: untreated wool has a natural water-repelling layer bonded to its surface, and the chlorine treatment breaks those bonds and strips it away. That's the same layer we want working on your feet.

I asked myself – choose between easy washing, or socks that keep my feet drier, dry faster and reduce blisters?

It’s a really easy one to answer.

- Shaun
Founder.

How to look after them

Untreated merino just needs a bit of respect in the wash. Our merino blend socks are an awesome blend of performance and durability (hence our 500 mile limited warranty) but they’re not invincible and Heat and rough washing are what shrink it.

Rules to wash by: