We mainly use Finnish PEFC-certified wood in our production that is sorted in accordance with our specific and strict requirements. The high and even quality of our production is based on a logistics chain that is carefully managed from forest to final product. Together with our suppliers, we select and use only the raw materials that are best suited for our production in terms of type and quality.
Pine grown in the northern latitudes is our main raw material. We only use sound knotted wood to ensure the high quality of the final products. As a result, Lunawood is known for its top quality.
The properties and quality requirements of the spruce that we use in production are similar to those of pine. Lunawood mainly uses spruce in the production of exterior cladding boards and other related products. In terms of production, knots are the main difference between pine and spruce: in spruce, the knots are smaller but relatively hard, which makes them break more easily during the processing.
Various other wood species are suited for thermal modification. Lunawood’s product selection includes two knotless wood species, thermally modified Radiata pine and European ash. Radiata pine is used in the production of knottless exterior cladding and interior products. European ash being denser and harder than softwoods, is excellently suited for the construction of decking and flooring.
Thermal modification of wood is a clean and ecological means to improve the properties of the wood. Only high temperatures and steam are used in the process, which makes the final product completely natural and chemical-free.
In thermal modification wood is treated with high temperature (+185 to +212°C). Water vapour is used as a protective gas and heat conductor that enables heating to wood beyond its auto-ignition temperature. The processing enables the properties of the wood to be modified to meet to the requirements of various uses. Varying the process allows the production of just those properties that are required in the end product. The treatment enhances various properties of the wood including dimensional stability, thermal insulation capability, resistance to decay, reshaping properties, and hygiene.
Thermal modification of wood can be roughly divided into three phases. During the first phase (see figure), the temperature of the wood is raised and it is dried. The second phase is the actual thermal modification of wood, during which the moisture content of the wood reduces close to zero and the temperature is at its highest. The maximum temperature and duration of the treatment is chosen based on the desired properties. Finally, the treated wood is cooled down and moisturized to the desired level.
Lunawood produces two standard heat treatment classes, Lunathermo-S and Lunathermo-D. The difference between the classes is in the heat treatment temperatures.
Lunathermo-S (stability) has an attractive shade of light brown and its dimensional stability is greatly improved. The wood is heat treated with milder temperatures (+185°C ±3). Lunathermo-S products are mainly for indoor use but can also be used in protected outdoor areas.
Lunathermo-D (durability) has a darker brown shade. Its resistance to decay and dimensional stability are greatly improved. Lunathermo-D is thermally modified using higher temperatures (+212°C±3), and the products are suited to both indoor and outdoor use.
Lunawood is a pioneer in thermowood on a global level. Combined with the world’s greatest thermowood production capability, this provides the company with endless opportunities to manufacture products that have just those properties that are required in their intended use.
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