Through the process of thermal modification, we open up a wide range of applications for our wood from Finnish forests, from exterior cladding and windows, doors and furniture to decking or flooring, landscaping and interior paneling. Please click below for our latest brochures with general information about TMW Raahe Oy or a closer look on our way of thermal modification as well as for a brief overview of profiles we offer.
Actually we summarize herewith the two main characteristics of our thermally modified wood. So, what do we mean with these terms are explained in detail below.
Finnland’s climatic conditions make our wood so special. The north of our land is mostly covered by ice and snow. Thereby, the vegetation period of the boreal coniferous forest extends to about short but intense 100 days.
The sun rarely sets these times, allowing the trees to take full advantage of the beautiful summer nights for growth. Their pursuit of light leads to a very straight shaped wood with only small notches. This makes it much more stable compared to this from same tree species grown elsewhere. That’s why we proudly name our wood “Finnish shaped”.
The process of treating wood with heat is not a recent discovery. Even the Vikings used wooden posts with a charred exterior when building their forts, as these lasted longer compared to untreated ones. But it was not until the 1990s that Finnish companies took a pioneering role and standardized as well as commercialized the thermal modification of wood. This technique enables us to improve the properties of our native spruces and pines to such an extent that they meet the standards for durability classes I to II. As a result, they become perfectly suitable for both interior and exterior use and eliminate the need for tropical woods. During thermal modification, we steam-heat our wood to temperatures up to 250°C. The absence of oxygen is imperative here, to prevent it from igniting. Still, the intended enhancements of its physical and chemical structure occur:
Its natural substances like (hemi-)cellulose and lignin are partially decomposed and expelled together with moisture and resins of our wood. In addition, organic acids, a by-product here, significantly enhance the resistance to microorganisms, fungi, and insects that cause decay. In this way, the weather resistance and durability of our wood is increased and it becomes more resistant to cracking, splintering, and bending. Its shrinkage and swelling is also greatly reduced due to a now very limited ability of water absorption. Finally, the high temperatures cause the sugar molecules in our wood to caramelize, giving it its typical brown color. The natural structure and grain are preserved overall, resulting in its beautiful appearance. All of these advantages are permanently, throughout our wood’s entire cross-section and result from a completely natural and chemical-free process. That’s why we proudly name our wood “Steam refined.”
We do not simply offer thermally modified wood. We are offering a solution, that has been grown and refined in line with Finland’s most important value: pure nature.
Finns are the happiest people in the world for the 6th year in a row, now. So, we would be happy to get in contact in with you and answer your issues – really.