Heat storage: the right wall structure for the sauna

Having your own small sauna is something great. It can stand in the garden or in the basement and is not so laborious to build yourself. The only important thing is the structure of the wall so that the heat is not lost again immediately.

Build a sauna yourself

A sauna basically consists of a wooden crate with seats or loungers and the appropriate heating technology. You can buy the latter complete with a temperature controller, but you build the wooden house yourself.

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Building the wall

The wall of a sauna consists of a wooden frame that is filled with insulating material and then clad.

Build studs

To build the statorwork, you need canted oils and screws. Then you have a frame with subdivisions for the insulation mats together.

Choose Kanthölzer, which correspond to the thickness of the insulation material, so that no unnecessary air is created in the frame later.

Dress first page

Then put a vapor barrier and the formwork on the outside. You can choose any material that you then treat with color or glaze (when the sauna is outdoors).


Now insert the insulation material. Optimally, you have set the longitudinal and transverse struts in the frame so that the insulating mats fit exactly and they only need to crop the material on the edge to the right size.

Attach the warmer reflector

A good sauna is not only insulated, it has a heat reflector on the inside above the insulation, which ensures that the heat that reaches the wall is reflected back into the room. An aluminum foil is usually used for this because aluminum reflects heat very well. At the same time, the film prevents the moisture that prevails in the sauna from getting into the insulation material.

Clad the sauna inside

Now screw roof battens onto the timbers of the frame. These slats create a space between the cladding and the aluminum foil so that moisture does not collect underneath.

Then you cover the sauna walls from the inside, again with a material of your choice. You should definitely use wood, not wood-based panels. Wood helps prevent mold from forming in the room despite the moisture, because it can absorb and release moisture as required.

Nevertheless, it is important that you ventilate the sauna well after use so that the moisture can escape. Because wood can store a certain amount of moisture, but not infinitely. It also gives off when the room cools down, causing condensation to settle in the coldest places.