INSULATION OF A BATHHOUSE WITH POLYURETHANE FOAM

What does a true banya require? Significant temperature and appropriate humidity (quite high) are the two main factors that distinguish a Russian banya from the steam rooms of other cultures. Traditionally, a steam room made of solid logs is considered a traditional building, but nowadays, more affordable materials are increasingly being used for banya construction. Therefore, the need for high-quality thermal insulation capable of providing the appropriate microclimate, regardless of the building materials used, becomes a pressing issue. Moreover, the roof, ceiling, and walls of such a modern banya must be insulated. The most rational comprehensive solution to this problem is considered to be thermal insulation based on polyurethane foam (PUF).

Why polyurethane foam

The main advantage of this material is its excellent thermal properties with a relatively simple installation method. Considering the modest size of a standard sauna, the overall cost of insulating with polyurethane foam appears quite modest. And considering the performance characteristics of PUF, this coating can be considered one of the most optimal options for thermal insulation of buildings available today.
According to experts, the main advantages of polyurethane foam include the following:

• Multifunctionality - the ability to insulate both external and internal areas of the sauna. Furthermore, the beneficial effect of using polyurethane foam for treating the roof and attic floor of the steam room is worth mentioning separately. The polyurethane foam coating significantly reduces heat loss through these structural components. This reduces fuel consumption and shortens the sauna's warm-up time.
• The polyurethane foam structure is characterized by 95% closed cells, which ensures minimal vapor permeability and moisture absorption. This not only ensures the required thermal insulation of the steam room but also effectively protects the sauna's wall structures from exposure to humid and hot air.
• The polyurethane foam is applied as a seamless layer over all treated surfaces, while the quick-hardening foam fills all existing cracks and voids in the walls. This monolithic insulation prevents the formation of "cold bridges" and the appearance of condensation on the interior surfaces of the sauna.

Another important advantage of polyurethane foam is its fire safety; the material is fire-retardant and self-extinguishing. This type of sauna roof insulation can significantly reduce the building's fire hazard. However, it's important to remember that maximum effectiveness can only be achieved by applying the required layer of thermal insulation to the roof (the inner surface of the roofing material), the ceiling, and the walls of the room.
 

Insulating the Roof of a Sauna

This work is most often performed from inside the attic, significantly reducing the cost of the work, allowing it to be performed year-round, and significantly increasing the durability of the sauna roof sheathing. Internal insulation of the sauna's attic space helps protect the load-bearing wooden roof structures from exposure to hot, water-vapor-laden air.
Internal roof insulation can be performed with virtually no preparation; simply cleaning the surface of debris and dust is sufficient. Polyurethane foam has excellent adhesion, so it adheres reliably to both wood and metal surfaces. It is recommended to treat not only the roof but also the sauna's attic floor in a single step, preventing any heat loss from the steam room.
Considering that polyurethane foam is certified for environmental safety, with this type of internal insulation, the sauna's attic can be used for storing bath whisks and other bath accessories. Polyurethane foam poses no health hazard, even with direct contact.
 

External or internal insulation of sauna walls?

Sometimes you hear the myth that polyurethane foam emits harmful substances when heated, but this information is untrue. The temperature at which the material's structure can begin to change is 150 degrees Celsius or higher. Such conditions are impossible to achieve in a sauna, and even then, polyurethane foam cannot cause harm to humans. Therefore, medical opinion is unequivocal: internal insulation of a sauna with polyurethane foam can be used without any harm to health. Moreover, the effectiveness of this insulation material is significantly superior to other traditional materials used in construction.