Finnish sauna, steam room or infrared cabin: the differences

Three quite different things that are often all called a sauna in everyday speech. They differ not only in temperature but in how they affect the body, what they cost to run, and whether they can stand in a garden at all. A barrel sauna is always the Finnish kind.

Finnish sauna: dry

80–100 °C at 10–20% humidity. Dry, strong heat carried by hot air.

Throwing water gives a short burst of steam and a sudden rise in felt temperature, the moment many people go to a sauna for. The Finnish word for it, löyly, has no real counterpart in other languages.

Heat-up takes 30–45 minutes. It is the classic version, and it is what you get in every barrel sauna, whether wood-fired or electric.

Steam room

45–55 °C at almost 100% humidity. A lower temperature, but it feels heavier: sweat does not evaporate and the body cools less well.

It needs a steam generator, a fully sealed, moisture-resistant cabin and a drain. In a timber structure in the garden it is practically never done: the steam would condense in the wood and destroy it within a few seasons.

It is a solution for indoor spaces, tiled or acrylic, with a complicated installation.

Infrared cabin

40–60 °C. The emitters warm the body directly, not the air, which is why you sweat despite the low temperature.

It heats up in a quarter of an hour and uses little electricity. No heavy-duty power supply is needed, which is often the deciding factor.

But it is a different experience: no steam, no water on the stones, no wave of heat. Many people do not consider it a sauna, and understand why after their first visit to a real Finnish sauna.

What you are comparing

Finnish sauna and infrared are not a choice between better and worse but between two different things. Finnish means intensity and ritual, infrared means convenience and a low barrier to entry.

A steam room comes closest to the Finnish sauna in intensity but needs a completely different construction.

What can stand in the garden

The Finnish one, meaning a barrel or cabin with a stove. It is the only version designed to stand outdoors all year.

Steam rooms and infrared are indoor solutions. An infrared cabin could in theory go in a garden room, but the emitters' electronics tolerate damp and frost poorly, and at 40 °C in winter the contrast no longer works.

The short answer

You want a sauna in the garden, with steam, with ritual and with the walk out into the frost: Finnish, so a barrel.

You want a quick warm-up indoors, without installation or moisture: infrared.

You want a steam room: that is an investment for the bathroom, not the garden.