For some reason this is the only screenshot I could find from when I was considering ventilation in my design. I ended up putting a vent in the bottom of the door, but rarely use it because the stove seems to pull in plenty of air through the 1/2" gap under the door. The vent up high and at the rear of the sauna I always open. Halfway for 1 or 2 people, and fully open for more than 2 people. I think a second upper vent would be justified at times.
