When building a sauna, there are three ways to consider setting up your sauna stove:
- Load wood from the outside
- Load wood from the changing room
- Load wood from inside the hot room
Options #1 and #2 involve using a ”throat” add on to a wood burning sauna stove. Also, one needs to brick around the throat and sauna, usually a three foot border, for fire retardant. In the old days, most saunas were built #1, loading wood from the outside. The main reason for this is that old saunas were inefficient, basically home made iron boxes that burned hot and fast, requiring a pretty much constant supply of firewood. Finnish ingenuity gave way to the idea that the door to the sauna stove could be steps away from an outdoor wood pile.
As stoves became a bit smaller and somewhat more efficient, people began building wood burning saunas to feed from the changing room. The theory here is that a small amount of firewood could be kept dry in the changing room and added to the stove from there. The main advantage to #2 is that the sauna stove can provide some heat to the changing room. It is estimated that between 10-15% of a sauna stove’s heat comes from the front of stove.
#3 is my choice. Today’s sauna stoves are very efficient. The Kuuma Stove is so efficient that I can take a sauna with 4 pieces of firewood. By feeding from inside the hot room, I capture 100% of the heat in the hot room, and don’t have to mess around with extensive brick framing. Also, I can monitor the fire from the sauna bench.