The right insulation material for the sauna

Regardless of which model of sauna you choose, it is important to have reliable thermal insulation. But what distinguishes such a sauna insulation? In what way can the heat storage capacity be increased? And what is the importance of individual factors such as wall thickness and material.

Sauna insulation: How to properly insulate your sauna

Reliable thermal insulation is essential for the various types of saunas, and for several reasons. After all, only an optimally selected insulation material ensures the ultimate wellness experience. That’s why no compromises should be made when it comes to precisely fitting insulation. Thermal insulation should not be put on the back burner when planning to build a sauna, but should be part of the planning phase from the outset. It is therefore essential to clarify how the insulation material should be before the actual construction of a sauna.

The correct thermal insulation of an outdoor sauna

Although all saunas require a certain type of insulation, the insulation material plays an even greater role, especially for outdoor saunas, for example, in the garden. This is because if the wrong insulation is chosen for an outdoor sauna, the heat inside the sauna cabin may be poorly retained or not retained at all, and electricity consumption will also increase immensely.

The type of wood used is a decisive criterion for thermal insulation

If the insulation is poor, the sauna heater simply needs more energy to build up a cabin temperature of 80 °C (176 °F), for example, and then to maintain it. However, it is not only the insulation that plays an important role in choosing the right material, but also its properties in general. Good insulation material must be resistant to heat and high temperatures.

It should also be strictly water-repellent, as well as absolutely non-toxic, that is, non-toxic. The material must therefore be harmless to health, even when exposed to heat. The tightness of an insulation also plays a role in sauna construction, it is primarily dependent on the planned average temperatures in the sauna cabin. The installed wood itself is also a decisive factor, because different types of wood have different properties in thermal insulation.

Cork insulation is particularly recommended from the point of view of safety

Different materials have proven to be particularly suitable for insulating a sauna. So-called mineral insulation wool, but also hemp or cork, are reliable materials to ensure reliable insulation in many cases. Cork not only provides excellent insulation, but also insulates well against sound. Thus, the heat is optimally kept inside the sauna cabin and noise from outside is kept away.

Cork is also considered to be only flame retardant, so it is also recommended from the point of view of safety and fire hazard. When choosing, the different cork variants should be considered, especially with regard to the different degrees of thickness. However, cork exudes an individual smell, not every sauna lover can get used to it. For most sauna fans, however, it is not a problem.

Purchase recommendation: cork board for thermal insulation

Very high quality cork board with a thickness of 40 mm. Used as thermal and sound insulation for walls. The insulating properties of cork are comparable to those of mineral-synthetic insulating materials.

Tepcor® Korkplatte Pinnwand 915 x 610 x 3-25 mm stark (40...

Special vapor barrier in sauna construction

The so-called vapor barrier, often made of aluminum, is also very important in terms of insulation. Laying the vapor barrier should always be done professionally and, above all, airtight. The resulting water vapor must not find its way into the masonry through cracks in the vapor barrier. Otherwise, the whole concept of insulation would be useless.

Purchase recommendation: Vapor barrier for sauna construction

Particularly stable sauna aluminum foil as a vapor barrier for the sauna walls with a high vapor tightness. A vapor barrier (aluminum foil) is a layer that is applied to the warm side of a building component (e.g. the inside of a sauna) in such a way that the diffusion of water vapor is impeded. Its purpose is to prevent unacceptably high moisture penetration of the insulating layer through diffusion of water vapor.

Angebot Spezielle robuste Dampfsperre für Saunabau, Aluminiumfolie,...

Hemp is very environmentally friendly as a renewable raw material

When insulating with hemp, it should be noted that there are still considerable differences in flammability in some cases. However, hemp is considered absolutely environmentally friendly, and in addition, the thermal conductivity of this natural material is very reliable.

Purchase recommendation: Stuffing hemp

Stuffing hemp is a natural and environmentally friendly alternative to PUR foams. Compared to construction foam, it has the advantage of being durable and permanently effective for centuries. It can be used wherever the penetration of cold air and the escape of warm air should be prevented.

Hanf Stopfhanf Ballen 25 kg Hanfdämmung Wärmedämmung...

Insulating with mineral rock wool

Mineral rock wool consists of countless rock wool fibers, the advantage of this type of insulation is the extreme heat resistance. Furthermore, mineral rock wool is completely harmless from a health point of view, but direct skin contact should be avoided at all costs. The tiny fibers of this insulation material definitely have considerable allergic potential and can cause itching in sensitive people. Anyone who wants to install mineral rock wool in insulation panels themselves should therefore be sure to wear appropriate protective gloves.

In addition, when planning with this insulation material, it should be noted that it is offered in different thicknesses. In many cases, the question arises as to why insulation is so important. When choosing the insulation material, for quality reasons, do not experiment, but choose only high-quality, approved materials.

Purchase recommendation: Insulation board made of rock wool

Best suited for partition walls with sound and fire protection requirements. Dimensionally stable rock wool insulation board for sound and heat insulation for partition walls in lightweight construction, which also meet fire protection requirements.

Rockwool Sonorock Trennwandplatte 60mm 5,625m² Dämmplatte...

Authentic sauna experience only possible with excellent insulation

Fiber insulation materials must, of course, not get into the room air inside the sauna cabin. Therefore, precautions must also be taken in this regard when selecting the appropriate insulation materials. Not only in terms of heating time, but also for reasons of energy and electricity consumption, thermal insulation of the sauna cabin can not be dispensed with.

So, no matter whether indoors or outdoors, no sauna will do without a functioning insulation. Which variant is the best, of course, also depends on the respective wall thickness. However, insulation does not have a significant impact on the actual lifespan of a sauna, as this depends on various other factors, but most importantly on the care of all materials and furnishings of a sauna.

Conclusion – Which sauna insulation has the best properties?

No sauna, whether indoor or outdoor, can do without reliable insulation. Today, thermal insulation for sauna construction is offered in many variants. Each material offers the user its individual advantages. Each material offers its individual advantages to the user.

No matter which variant you choose, it depends, among other things, on the appropriate wall thickness. Especially if you have decided to take the construction of the sauna into your own hands, it is important to get comprehensive information about the “perfect” insulation. In this way, you can significantly reduce the power consumption of your sauna.

Purchase recommendation: sauna insulation board

SPU Sauna Satu is used for wall and ceiling insulation in saunas and ceilings in damp rooms. The amount of Kingspan SPU Sauna Satu required is only about half the amount that would be needed for mineral wool. For example, if you install SPU Sauna Satu on the wall, the space can be increased up to 10 cm. The aluminum surface reflects heat back into the room, improving thermal insulation.

Kingspan SPU Sauna Dämmplatte 600x1200x30mm


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