Selecting the heater
The volume and structures of the sauna affect the selection of heater. An average of 1 kW of heater power is required for each cubic metre of sauna volume. The power requirement increases if there are window surfaces or heat-storing surfaces such as brick, concrete or non-insulated log in the sauna.
When building or renovating your sauna room, remember that the walls and particularly the ceiling require good thermal insulation. One square metre of stone, glass or similar noninsulated surface increases the heater power requirement as much as if the sauna room cubage were increased by 1.2 cubic metres. If the interior wall of the sauna room is noninsulated log, multiply the cubic volume of sauna by 1.5. You should also pay attention to sauna room ventilation. Efficient air circulation ensures that the bathers can enjoy clean air that is easy to breathe.
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