It is important to note that colder air mass will always try to move downwards. Room temperature air in the sauna sinks down to the floor level unless it can be circulated properly with the air mass inside the sauna. To achieve the “natural draw effect” and to pull fresh air through the sauna room, it is imperative to position your in-vent directly under the heater so that the heat of the rocks, accompanied with Finnleo’s open air heater design, can properly pull new air into the sauna room. Place the exhaust vent opposite your heater in-vent (as closely as possible) to your maximize air exchange and to optimize the level of the out-vent (which is most often positioned 2 feet above the floor). The goal is to avoid heat loss, while still keeping it high enough to achieve adequate air exchange. If mechanical venting is desired, please contact our technical staff or your local dealer for more information relating to venting your sauna properly.