Hugo Morvan wrote:What Kyle says resonates true with my sauna building experience.
What i gathered is that you need to have the air flow going into the sauna from the bottom close to the place where the stove is to get fresh oxygen in and a hole up high to the outside world so heated air can leave as well to guarantee enough air flow (oxygen) for the sauna-takers. When battling the heat you don't want to feel that you can't breath on top. The blast of heat in a small space is sufficient to get temperatures to boiling point. That is with a regular sauna wood stove, the power of a rocket stove is much bigger and will heat it up superfast. People manage to build a sauna in a tent even. Following that line of thinking you could argue no insulation at all.
My experience is that some people, mostly females prefer less hot temperatures so they go in at the beginning in a normal set up and the men join a bit later. With a rocket stove it gets hot really quick, and then you lose your heat rapidly if not insulated at all. Then you have to light another fire, which is quite messy when you're wet and sweaty and want to relax. It's something to take into consideration. A normal sauna stove is quite a bulky metal thing and has the lava rocks on top, which heat as well and serve as a thermal mass. Lovely to throw water on there infused with some eucalypthus or a hydrosol of pine tree.
Nothing gets you more thoroughly clean then a sauna. All the pores open and gush out sweat and dirt. I have a shower adjacent , the cold water makes me resistant against the heat for a bit longer and when heated up it makes me resistant for a bit against the cold water. A lake would even be better a place where you can take a dip in.
I had a sauna party with many people and a kid almost touched the stove so build a little light weight safety rack. Heavier at bottom , because of the log base, light hazel standing wood and tied together by willow.
Air inlet next to stove is the door is 3 inch short.