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What is Thermo-Wood?

When searching for the perfect sauna for your home, you will notice that select models are made of thermo-wood, especially with our fine Forever Saunas selections. Thermo-wood is the official term for heat-treated wood. Exposing wood to heat in a controlled environment makes it more durable and weather-resistant while preserving its looks and qualities. 

Treating wood with fire is an ancient method, long used by various cultures to turn long sticks of wood into sharp spears or to make wood planks more resistant to insect infestation and rot. Fire removes moisture from the wood and changes its composition. Nowadays, there are a lot of methods to make wood stronger and have a longer useful life. 

Aside from being ideal for saunas, manufacturers prefer heat-treated wood because it weighs less, resists warping, and is easier to work with. Outdoor saunas are exposed to the sun and rain, and regular use of  saunas exposes the wood to repeated cycles of moisture and drying. Therefore, saunas must be built using a durable material. We will pay great attention to why thermo-wood is a good choice for your next sauna. Continue reading! 

Why is Thermo-Wood Beneficial for Saunas?

Although there are several modern methods to make wood stronger, manufacturers still prefer to make sauna cabins with thermo-wood for good reasons. Thermo-wood looks and feels natural. Understand that most fine sauna cabins are made of long-dimensional wood planks, so the treatment should preserve the wood's look, feel, and aroma. That is especially true when using beautifully rustic aspen or spruce wood plants for the sauna cabin – it would be a shame to stain or paint these gorgeous woods, right?

Speaking of wood types, aspen and spruce are the ideal choices for sauna cabins. Aspen and spruce are popular for sauna construction due to their durability and resistance to decay. Both retain their desirable characteristics and appearance with heat drying. Treatment also extends their useful life and resistance to weather. With thermo-wood, you can enjoy its beautiful appearance as you relax in your sauna, and feel the fine wood grain with your fingertips and smell the subtle woodsy scent.

Another important advantage of thermo-wood is the distinct lack of use of preservatives, glues, and salts, unlike in other wood products. Exposure to heat and moisture tends to release these compounds, so most other types of wood products are not used in sauna cabins. You do not want to breathe in these chemicals as you enjoy a sauna session. 

When done properly and with proper maintenance, thermo-wood can last longer  than any other type of wood. It has a low moisture content and does not absorb water from the air easily, which makes it more resistant to rot. In addition, thermo-wood has good insulating properties, so the sauna cabin retains heat and conserves energy. Most sauna cabins, like those in the Forever Saunas line, have shingles that serve as the roof that protects the cabin from rain and snow. 

How Do They Make Thermo-Wood? 

There are several methods to make thermo-wood, and the process is complicated. It is more than just exposing wood to a heat source. Almost all timber is processed by heating as part of the wood seasoning process. Heat kills insects that can cause infestation and reduces moisture content, so the wood shrinks in size and becomes more durable. 

For use in saunas, the production of thermo-wood comes with extra steps. Manufacturers use an airtight oven with sensors called a kiln, which is large enough to house thousands of cubic feet of sawn lumber and still have space for circulating air. Humidity levels are carefully controlled while the wood is heated up to the north of 419°F (or 215°C) for several hours to days, depending on the type of wood used and the moisture content. The air circulation is also carefully controlled to ensure that the resulting product has a uniform appearance without warpage or cracks. 

The trick here is that natural wood varies greatly on its condition, porosity, moisture content, and presence of defects, so the process is closely monitored to prevent the wood from swelling, cracking, or warping. Thermo-wood does not use chemicals or produce waste products, so it is friendly to the environment. 

What About Other Types of Wood Products?

Due to reasons stated previously, other wood products may not be suitable for sauna cabins. Wood products are often impregnated with chemicals that may leach into the air due to repeated cycles of high humidity and heat. You can try having a sauna made of actual wood logs, but the resulting cabin will be heavy and difficult to assemble. 

Since you probably want a nicely-built sauna cabin, choosing thermo-wood is the way to go. Choose models that only use such wood throughout, including the benches, armrests, wall panels, and floors, for a genuine experience. It is chemical-free and affordable, and the sauna cabin will be durable and easy to build.

Choose Your Sauna Carefully and Buy Now!

There are well-built sauna brands made exclusively with thermo-wood, like Forever Saunas. The cabins are made of thermo-spruce which is naturally low in moisture content, so it is fairly resistant to rot. Spruce is also light in weight, so the sauna cabin is easy to assemble at your home. Natural spruce exhibits fine grain and a beautiful pale color that adds a luxurious touch to your space. Meanwhile, aspen is prized because of its faint forest aroma and resistance to splitting. Aspen is great for seats because it has fine, even grain and texture. No tropical hardwoods are used in the cabins, so you will surely have a well-built cabin that will last for many years. 

If you want to know more about thermo-wood, please visit a related blog at My Sauna World. If you want the best thermo-wood saunas available, please browse our collection of Forever Saunas. We have a beautiful collection of barrel saunas, including spacious four and six-person sauna cabins so you can relax and lounge! In addition, we have cabins that have windows and full front glass for amazing views. Shop Forever Saunas now and enjoy having a fine sauna in your home!

Use coupon code WELCOME10 for 10% off your first order.


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