When choosing wood for a wood-fired font, it is important to pay attention not only to the type of wood from which it is made. Strength, moisture resistance, thermal conductivity and other characteristics of the material that cannot be achieved without additional processing matter. The best option would be Finnish thermowood. It is a material with unique properties, resistant to mechanical and chemical influences. And if we are talking about a font on wood, then this is especially important.
Thermoboard: what is it and why is it needed?
Finnish thermowood is wood treated at high temperatures. She has no analogues, and all thanks to a special technology patented by specialists from Finland.
Heat treatment is carried out in several stages. The wood is heated in a hermetically sealed chamber. The temperature is gradually increased to +240°C, and the humidity is reduced to zero. Despite the strong heating, the tree does not catch fire, because there is no access to oxygen in the chamber. Then the wood is cooled, and its moisture content is increased to 4-6%.
Heat treatment according to Finnish technology affects the wood molecules: it becomes less porous and more dense in structure. At the same time, toxic substances are not used for its modification. As a result, we get a completely environmentally friendly and safe material.
Finnish thermowood has many advantages. Let’s highlight the main ones:
- Low thermal conductivity. Finnish thermowood practically does not heat up at high temperatures – its thermal conductivity decreases by about 25%;
- Increased strength. Thermal wood during processing becomes 5-20% denser, and, accordingly, stronger. Wood processed using this technology does not crack or wear out for several decades;
- High moisture resistance. Ordinary wood swells with constant exposure to water. The thermal board is denser, therefore it absorbs 5 times less moisture. Even with daily contact with water, the material retains its original properties;
- Pest resistance. Wood contains wood sugars that attract bacteria, fungi and insects. During heat treatment according to Finnish technology, these substances decompose, so thermal boards are reliably protected from mold, rot and pests;
- Environmental friendliness. Thermowood is absolutely non-toxic, therefore it is safe for your health. And due to the fact that the tree undergoes only temperature, and not chemical treatment, it retains its natural aroma, which intensifies when heated.
But one of the main advantages of thermal boards is durability. And these are not just big words: Finnish thermal wood lasts at least 10 times longer than ordinary wood, even varnished and impregnated.
Finnish thermowood for hot tubs
At FinSpa , we believe that thermal wood is the ideal material for a wood-fired spa. Hot tubs made from Finnish thermal board withstand regular use and do not lose their characteristics at all. In addition, a spa made of simple treated wood needs to be periodically repaired: varnished, impregnated with protective liquids, glued. Thermowood fonts do not need this, since the material itself is strong and durable.