Aluminum foil, Dnipropetrovsk region.

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Aluminum foil for bath and sauna, 30 square meters, 13 μm.
Thermal insulation for saunas and baths is made indoors and, most often, mineral wool is used for this purpose, which has a number of advantages: it does not deteriorate under the influence of high temperatures, characteristic of a steam room, and does not rot. It is also recommended to sheathe the ceiling and walls with cotton wool and plates based on mineral fibers, and so that such insulation does not lose its useful properties over time, it is worth thinking about vapor insulation in advance. This will be helped by aluminum foil paper, which perfectly seals and reflects the radiation of heated objects.
Thermal insulation is especially important for a Russian bath, since the level of humidity in it is twice as high as in a sauna. However, in any case, the use of materials that emit toxic substances when heated is unacceptable.(//tractor-service.com)
The use of aluminum foil in the construction of baths and saunas allows you to preserve the full range of thermal radiation inside the room as much as possible. It provides fast heating and long-term preservation of heat with lower heating costs (THERMOS EFFECT). Installing foil in baths and saunas directly on the ceiling and walls under the paneling with the polished (mirror) side inside the room gives a tangible thermal effect. Such a design scheme quickly heats up and retains heat for a long time.
Vapor barrier metallized material foil paper is made on the basis of kraft - paper with applied aluminum foil. The material is mostly intended for use in steam rooms. Its use allows you to significantly reduce the escape of steam, reduce heat loss through the walls (reflectivity of the aluminum layer exceeds 95%) and prevent dampness in the walls arising from periodic changes in temperature and humidity inside the room. The absence of polymers in the constituent elements of the material indicates the possibility of using foil paper in a high-temperature environment of more than 100 °C, i.e. in saunas, where the temperature of dry steam reaches 100-120 °С.

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