If you've ever stood in a sauna in a polyester swimsuit and felt like you were slowly being cooked, you're not alone. There's a better option — and it's not what you'd expect.
Merino wool swimwear performs exceptionally well in saunas, steam rooms, and hot pools. Unlike synthetic fabrics that trap heat and cling as you sweat, merino actively regulates your body temperature — keeping you comfortable whether you're in the heat or moving between hot and cold environments.
It sounds counterintuitive. But once you understand how merino handles heat and moisture, it makes complete sense.
Why merino works in a sauna or spa
Merino is a natural temperature regulator — it works in both directions, keeping you cool when it's warm and warm when it's cool. In a sauna or steam room, that means it manages the heat rather than amplifying it.
The lanolin in merino fibres also resists odour naturally, which matters in a shared spa environment. And because merino absorbs moisture gradually rather than sitting wet on the surface, it doesn't feel heavy or clammy as you move between environments.
How we found out
We designed swimm for the water — ocean swims, pool laps, beach days. Saunas and spas were never part of the plan.
Then our customers got involved. Messages started coming in from people who'd worn their swimm pieces into the sauna at their gym, the steam room at a day spa, the hot pools at a thermal resort. The feedback was consistent: it felt completely different to anything they'd worn in those environments before.
We hadn't designed for it. But the fabric didn't care — it just did what merino does.
A note on care
Rinse in cold water after sauna or hot pool use and lay flat to dry — same as after a swim. The minerals in some thermal pools can affect any fabric over time, so a prompt rinse goes a long way.