Traditional Finnish saunas have been used for centuries as a way of relaxing and rejuvenating the body. Saunas, in basic form, are insulated, heated wood rooms.
Unlike newer infrared saunas that heat the objects in the room, traditional saunas heat the air within the room. Traditional saunas are generally lined with low-density soft woods that can resist heat rather than absorb it, so that it is comfortable to the touch once the room is heated.
Excellent woods for saunas include redwood, cedar, spruce and eastern white pine. Construction can be made simple with pre-fabricated sauna kits which include all of the necessary materials--from the hardware, stove and benches to doors, wood panels, frame and ceiling.
Custom-cut kits are also available so the sauna can be built to the owner's specifications.
Traditional saunas are heated by electric, wood or gas stoves. Wood stoves are generally the cheapest, and for some individuals they provide a more "authentic" sauna experience.
Gas stoves are inexpensive as well, although a gas line installation is required to run the stove. Electric stoves are the most expensive option, although they are the most compact and efficient type to use.
The amount of energy that the stove produces needs to correspond correctly with the size of the sauna. If the stove is too small for the room size, the sauna will not heat effectively.
The role of the rocks
Traditional saunas provide high heat with low humidity. Temperatures generally range from 185 to 195 degrees F.
The rocks within the sauna stove distribute the heat. Small pieces of igneous granite work best, since they can easily absorb high temperatures without cracking.
Once the rocks have been heated (time ranges between 30 and 45 minutes) and heat is distributed throughout the room, hot water is poured on them to create steam. This steam creates the relaxing, cleansing experience.