Thermally treated aspen is an ideal material for sauna benches, as thermal treatment significantly improves aspen’s natural properties. Due to the treatment, the wood’s moisture movement decreases, durability improves, and thermal conductivity reduces, making it pleasant against the skin in a sauna. Thermally treated aspen is also naturally knot-free, resin-free, and splinter-free material, whose beautiful, dark shade creates a luxurious atmosphere in the sauna.
Why does thermal treatment improve aspen’s properties for sauna use?
Thermal treatment changes aspen’s chemical structure, making it essentially more durable and stable material for the sauna environment. In the process, the wood is heated to a high temperature (typically 160-220 °C) under oxygen-free conditions, permanently altering its cellulose and hemicellulose structures.
As a result of this process, aspen’s moisture movement is significantly reduced, which means that bench wood doesn’t react to the sauna’s varying moisture and temperature conditions. The dimensional stability of the bench wood improves and cracking decreases, which considerably extends its lifespan.
Thermal treatment also reduces the wood’s thermal conductivity, which makes thermally treated aspen feel pleasant against the skin even in a hot sauna. Thanks to the thermal treatment, aspen doesn’t heat up as quickly as untreated wood, so its surface feels more comfortable for the bather.
Additionally, thermal treatment makes aspen biologically more durable, which improves its rot resistance in humid conditions. This is an especially important characteristic in the sauna environment, where moisture and heat create favorable conditions for microbial growth.
What are the key benefits of thermally treated aspen as sauna bench material?
The most significant advantage of thermally treated aspen as bench material is its excellent thermal property – it doesn’t heat up quickly and remains pleasant against the skin even in hot steam. This makes the sauna experience more comfortable and safer.
Another important advantage is the material’s hygiene. Thanks to thermal treatment, aspen withstands moisture better, which reduces the growth of mold and other microbes. Additionally, the wood is a naturally antibacterial material, making it an excellent choice for sauna environments for hygiene reasons.
Thermally treated aspen is also an exceptionally durable material. It withstands well the extreme conditions of a sauna: continuous variation between moisture and dryness, as well as high temperatures. This extends the bench wood’s lifespan and reduces the need for maintenance.
In addition to practicality, thermally treated aspen is an aesthetically pleasing choice. Thermal treatment gives aspen a beautiful, warm brown shade that brings a luxurious atmosphere to the sauna. The material’s smooth, splinter-free surface is pleasant both to look at and touch.
How does thermally treated aspen compare to other bench wood alternatives?
Thermally treated aspen offers an excellent balance between comfort of use, durability, and appearance compared to other bench wood alternatives. Compared to black alder, another popular bench material, thermally treated aspen has better dimensional stability and withstands the sauna’s moisture variations better.
Black alder naturally has a beautiful reddish shade, while thermally treated aspen is darker and warm brown in color. Both materials are knot-free and resin-free, making them excellent bench wood alternatives. The choice between these two is often aesthetic – whether you prefer black alder’s natural reddish or thermally treated aspen’s deeper brown shade.
Thermally treated radiata pine is another alternative, which is often more affordable than thermally treated aspen. Thermally treated aspen, however, is more durable and more pleasant against the skin due to its density and structure. Aspen is also naturally more knot-free and more consistent material than pine.
Compared to untreated aspen, the thermally treated version is considerably more durable and stable, making it a longer-lasting choice for sauna bench wood. Thermal treatment also deepens aspen’s natural color and highlights its beautiful grain pattern.
What special considerations are there in choosing and using thermally treated aspen?
When choosing thermally treated aspen, it’s important to pay attention to the quality of the material and the uniformity of the treatment. High-quality thermally treated aspen is knot-free, evenly colored, and free of cracks. High-quality bench wood is also precisely planed, ensuring a smooth and pleasant surface.
In installation, it should be noted that although thermally treated aspen moves less than untreated wood, it’s still good to leave small expansion gaps between the boards. Fastening should be done with stainless-steel fixtures to avoid rust marks on the wood.
Thermally treated aspen doesn’t require special surface treatment, but regular cleaning extends its lifespan. In sauna cleaning, it’s advisable to avoid strong chemicals that can damage the wood’s natural properties. Mild sauna cleaning agents and regular ventilation are sufficient to keep thermally treated aspen in good condition.
Over time, thermally treated aspen may fade slightly due to sunlight, especially in saunas with windows. This natural patina is often considered aesthetically pleasing, but it’s good to be aware of when choosing the material.
Why is Finnish aspen particularly suitable material for saunas?
Finnish aspen is excellent sauna material because it grows in the demanding northern conditions, making it dense-grained and durable. Finnish aspen has fewer knots and its quality is more consistent than in many other aspen species, making it an ideal bench material.
Domestic aspen is also a responsible choice. Finnish forest management is sustainable and closely regulated, ensuring the raw material’s ecological credentials. Using local material also reduces emissions from transportation and supports domestic work and expertise.
Finnish aspen has a long tradition in sauna culture. It has been a valued bench material for decades before the development of thermal treatment technology. Thermal treatment has further improved the properties of this traditional material and made it one of the best high-quality bench wood materials available bench wood alternatives on the market.
Genuine Finnish raw materials complement Finnish sauna culture well, which values quality, durability, and naturalness. When using Finnish aspen, the sauna is a genuinely Finnish and high-quality entity.
At Pieksäwood, we manufacture high-quality sauna wood products from Finnish aspen in Pieksämäki, in the heart of Savo. With our over 20 years of experience in thermal treatment and our modern production line, we can offer products that meet even the highest quality requirements. We control the entire manufacturing chain from our own sawmill to finished planed products, which guarantees consistent quality and responsible production. You can see examples of high-quality sauna implementations in our reference gallery.