What is löyly?

The word

Finland's official country site describes löyly as the steam made by throwing water on the heated stones, which raises the humidity. (thisisFINLAND (Ministry for Foreign Affairs of Finland))

The Finnish Sauna Society says a heater warms the room and the bathers and also turns water thrown onto the hot stones into steam.

Temperature

thisisFINLAND reports that the Finnish Sauna Society recommends a hot-room temperature of 80–100 °C (176–212 °F), while noting some people prefer about 70 °C. (thisisFINLAND (Ministry for Foreign Affairs of Finland))

Harvia says that at 80–100 °C the air may feel dry and the steam sharp, even when water is thrown on the stones. Harvia says at lower temperatures of 50–60 °C you can use plenty of water and the air feels humid and soft.

Humidity

NASS says relative humidity in a traditional sauna ranges from as low as 10% with no water to 60% or more. NASS puts typical Finnish sauna humidity with a fair amount of water on the rocks at 25–35%. (North American Sauna Society; North American Sauna Society)

NASS says a "dry" sauna is simply a Finnish sauna with no water ladled onto the rocks. (North American Sauna Society)

Throwing water

HUUM recommends ladling about 80 ml (2¾ oz) of water at a time and waiting a few minutes before the next ladle. Finnleo advises sprinkling one ladle of water at a time rather than pouring or dumping it.

Wood-heated saunas

The Finnish Sauna Society says a heat-storing wood heater is heated before bathing and usually takes a few hours to heat.

Read next

• Sauna stones
• Sauna ventilation
• Traditional vs infrared sauna