Placing the sauna on an even surface that can bear the weight of the sauna is important. The surface can be evened out with stone chippings, or if you want to have a more solid foundation, you can cast one from concrete. If you want to insulate the sauna foundation, we recommend placing at least 5–10 cm of ground frost insulation under the gravel, which effectively cuts off the thermal bridge to the cold ground underneath. Under the sauna, we recommend placing 9 concrete slabs on top of the hard surface to lift it higher (see the image of the foundation) and putting roofing felt (bitumen roofing) on top of the slabs throughout the width of the sauna. When the base of the sauna is clearly up in the air, it has ventilation and dries well.
Foundations
Make sure that the ground on which the sauna is placed is stable. If necessary, the base of the sauna can be evened out with stone chippings or a concrete casting can be made under the modules. If you want to insulate the base, we recommend placing at least 5–10 cm of ground frost insulation under the gravel, which effectively cuts off the thermal bridge to the cold ground underneath. Never place the sauna directly on the ground. Pay attention to potential maintenance activities when choosing where to install the sauna. The warranty does not cover any indirect costs, such as the demolition or construction of terraces. Before building a foundation, it is also good to prepare for the drainage of water from the sauna to its final location (the sauna already has its own drainage installed).
Screw piles
There are various sizes, lengths and types of screw piles on the market. The selection is wide, because the choice of screw pile is also influenced by other things than the size and load capacity of the screw pile. The appropriate model is selected according to the type of soil and the depth of the frost line. You can install screw piles yourself, but ask a professional for advice on choosing a suitable model. 81
Concrete slabs
Under the sauna, we recommend placing concrete slabs on top of the hard surface to lift it higher and putting roofing felt (bitumen roofing) on top of the slabs throughout the width of the slab. When the base of the sauna is clearly up in the air, it has ventilation and dries well. It is also important to ensure that the sauna is not surrounded by tall grass, because it prevents the wood from breathing and contributes to rotting. The lower parts of the sauuna must always have enough ventilation. Below more detailed measurements of the concrete slabs.