The sauna is a small, tetragonal, cross-timber building with an insulated ceiling and walls. The building usually consists of two rooms – a vestibule and a steam room. The steam-room contains a big, cobble-stone piled stove, benches for sitting and the sauna platform where one can sit or lie down. This room also has containers filled with water which can be used for washing or refreshing yourself.

Sauna-goers can cool themselves down in the vestibule, which also has benches for sitting and pegs for hanging clothes. Wash-basins and other sauna equipment can also be found in this room.

Light comes in through small windows or a ventilation slot. During hours of darkness, candles and lamps are used. Generally, there is no electricity supply due to the distance from other buildings and the presence of heat and humidity.

Saturday was usually designated as the sauna day, but the sauna can be heated on other days as well, if required. Heating up a smoke sauna takes several hours, which is why one starts to heat the sauna around noon, making it ready to enter before the evening darkness.

The quality of a smoke sauna depends greatly on the heating process. Every sauna is a little different and it should be heated by a family member who is well acquainted with its unique character. In former times, the sauna was heated by elderly women. This custom may not have survived to the modern day, though there is still a designated person tasked with the heating.

The sauna is heated with wood from dry deciduous trees, alder being considered the best firewood. Firewood is added to the sauna stove several times during the heating process, but the definitive heating time depends on the size of the sauna, the outside temperature and the peculiarities of the sauna stove. More firewood is added as the previous batch is consumed. Initially there is much smoke in the sauna, so the door is kept a little ajar to allow the smoke to escape more quickly. At some point during the heating process, the sauna starts to “eat the smoke” – a distinct smoke border forms about one metre above the floor. The formation of the smoke border signals that the heating process is more or less half-finished, at which point the door is closed, but smoke still comes out through the crevices.

When the last batch of firewood has been burned, the sauna must be ventilated and left with closed doors for about an hour. Before sauna-goers enter the building, “harsh steam” is thrown into the heater to clean the air in the sauna one last time. This steam is released through the door, and the sauna benches and platform are swept clean as well. Dry threshing whisks are placed in hot water to soak. The sauna is then ready for use.