Most people who own a sauna hat use it correctly without knowing why it works. Most people who don't own one assume it is decorative. Neither is quite right.

The sauna hat has one function: to insulate the head from direct heat so the session can run longer. In a sauna at 80 to 100 degrees Celsius, heat concentrates near the ceiling. A person seated on a bench has their body at a cooler level — but their head at a hotter one. Without insulation, the head reaches its tolerance threshold before the body has finished its work. The hat creates a barrier between the scalp and the hot air, raising that threshold and allowing the session to continue.

How to use it correctly:

Put it on before entering the sauna. Not after the head has already been exposed to peak heat — before. The hat works by maintaining a stable temperature at the scalp from the start of the session, not by cooling a head that has already overheated.

Wear it throughout the session. The hat is not needed between rounds — remove it in the cooling period and replace it before the next round begins.

In a Finnish-style session with löyly — ladling water onto hot stones to produce steam — the hat becomes more important with each round. The bursts of intense steam that löyly produces are exactly the conditions the wool brim is designed to intercept before they reach the hair and scalp.

Hang it between sessions. A loop handle at the crown of the PP sauna hat allows hanging on a hook or peg between rounds. This keeps the felt dry rather than leaving it to absorb ambient moisture from the bench or floor.

After the session, hang to dry fully before storing. Wool felt that is stored damp will develop an odour over time. A few minutes hanging in cool air after each session is all the maintenance required.

The sauna hat is one of the few accessories whose entire value is functional. That is also why it is worth choosing correctly.

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