Building a greener tomorrow, one board at a time! www.thermalwoodcanada.com
ThermalWood Product Information Background It has been known for centuries that burning the surface of wood in open fire will make it more durable in exterior use. Even the Vikings used this method in tools and outdoor structures. Heat treatment of wood was scientifically studied in the early 1900 s in Germany and the US, and has since become an increasingly researched and developed technology. More recently, in the 1990s, research work has been carried out in Finland, France, and the Netherlands. The most intensive and comprehensive research work was conducted by the VTT technical research centre in Finland. The Manufacturing Process ThermalWood is manufactured using a method developed by VTT. The process is based on the use of high temperature and steam with the wood material heated to a temperature of at least 180 C. Besides providing protection from burning and cracking, the steam also affects the chemical changes taking place in the wood. No chemicals are used in the treatment, resulting in an environmentally friendly product. It is more stable than normal wood in conditions of changing humidity, and its thermal insulation properties are improved. If carried out at a sufficiently high temperature, treatment also makes the wood resistant to decay. The process enhances the grain and deepens color. The ThermalWood process which is patented by the Finnish ThermalWood Association can be divided into three phases: 1. Temperature Increase and kiln drying: The air and wood temperature in the kiln is rapidly raised using heat and steam to a level of around 100 C. Thereafter the temperature is increased steadily to 130 C and drying takes place. Either green (un-kilned) or kiln-dried raw material can be used. Steam is used as a vapor membrane to prevent cracking of the wood. The steam also facilitates chemical changes taking place in the wood. At the end of this phase the moisture content is reduced to almost zero. 2. Intensive Heat Treatment: During the intensive heat treatment phase the air and wood temperature is increased to a level of between 185 225 C. The peak temperature depends on the desired end use of the material. When the target level is reached the temperature is held constant for 2 3 hours. Steam is used to prevent the wood from burning and cracking and it also continues to influence the chemical changes taking place in the wood. 3. Cooling and Moisture Conditioning: The temperature is reduced using water spray systems. Conditioning and re-moisturizing takes place to bring the wood moisture content to a workable level over 4 percent. 1
ThermalWood Processing Stages The intense heat in the ThermalWood process results in a number of desirable physical and aesthetic properties including an enhanced grain pattern and a richer, darker color. Treated & Untreated Aspen Temperature Effect Treated & Untreated Birch 2
Environmental Aspects Since no chemicals are required and only water and heat are used, the ThermalWood process is environmentally friendly. Extractives released from the wood by the treatment are processed - for example by burning to avoid any odor nuisance. The relatively small amount of waste water generated during the processing is piped to a waste water works after the solid components are separated out in a special settling basin. When used for outdoor materials the life expectancy is considerably higher than that of non-thermally modified wood, reducing the frequency of maintenance and replacement of installations such as decking. Another notable benefit of thermally modified wood is the reduction in thermal conductivity in the finished product, resulting in an increase in the insulation properties of the wood. When used for exterior cladding, heat/electricity costs can be reduced. Key Characteristics Density / Strength - Density (kg/m3) is determined by measuring the weight and dimensions of a sample. On average the ThermalWood process reduces the density by approximately 10 %. Generally the strength of wood has a direct co-relation with density and as the process slightly lowers the density, the strength value is affected, but there is minimal change in the weight-to-strength values. Bending Strength / Modulus of Elasticity - Material treated at temperatures below 200 C does not experience a significant loss in bending strength, while a significant loss in bending strength can be found in material treated at temperatures above 200 C. The ThermalWood process has been found to maintain or even slightly improve the modulus of elasticity. At this stage further testing is required before tables are available for specifying horizontal load bearing structural usage. Compression Strength - The Compression strength is mainly dependent on the actual density of wood. According to tests it is has been found that the ThermalWood process has no significant effect on the compression strength values. Splitting Strength - The process can cause some reduction in the splitting strength depending on treatment temperature; the reduction increases as the temperature goes over 200 C. Screw Holding Strength - The screw holding strength has a strong correlation with density. The main effect on screw holding strength comes from the general variance in wood density rather than from the ThermalWood method. It was found that material with lower density has better results when narrower pre-drilled holes are used 3
Moisture - In regard to moisture content and stability the ThermalWood process leads to a reduction in equilibrium moisture content. When treated at the highest temperatures the equilibrium moisture content can be 40-50 percent lower compared to untreated wood. Because of lower equilibrium moisture content and the changes in the chemical composition of the wood, the tangential and radial swelling decreases significantly compared with untreated material. In some cases the reduction in dimensional movement can be as much as 40-50%. Permeability - In terms of permeability, ThermalWood reduces the water uptake of wood; the levels may differ depending on the original wood species. Another positive factor of the finished wood is its thermal properties, the thermal conductivity is 20-25 percent lower compared to untreated wood, thus providing an improved insulation factor. Tests made under laboratory conditions have proven a significant improvement in biological durability. Improvements in biological durability are a result of the removal of natural food sources in the wood and also changes in the chemical and structural composition. Levels of resistance to fungal decay increase as higher temperatures are used. 4
Naturally Aesthetic One of the biggest attributes of the finished product made of thermally treated wood is its aesthetics. Depending on the temperature and length of the process, different hues of brown can be achieved; and this darkened shade in the finished product is consistent throughout the entire piece of wood - making it ideal for wood working and furnishings. 5
ThermalWood Products and Services Currently ThermalWood Canada s main product focus is on the initial process itself supplying thermally treated lumber. The oven in the Bathurst facility has a capacity of 16,000 board feet, (smaller batches can be combined). Processing rates per 1,000 board feet allow customers to supply their own wood, which is prepared, loaded, thermally processed, packaged and skidded for return shipment. All processing stages are quality controlled to ensure the selected processing program is rigorously adhered to. ThermalWood is also able to provide the raw wood for customers at the additional cost of the wood itself. Some operations such as sizing and milling for value-added products can also be provided at the facility. Most local wood species have been treated with the ThermalWood process - the main product being Red Maple and Red Pine. The quality of these indigenous species makes them exceptionally suited for this process. Species from other areas are similarly treated with the process and the modified wood is used for a wide range of products ranging from flooring and finger-jointed plywood for wall paneling from guitar necks to musical instrument bodies. ThermalWood Decking is an innovative ground level decking system that uses a concealed fastening system (Clip Juan) with a product that is superior in quality, aesthetics, and resistance to fungal degradation. This decking product is manufactured in several styles, sizes and species of wood. ThermalWood Siding can be manufactured to a specified profile, and uses the same concealed fastening system. The ThermalWood Flooring and ThermalWood Garden Line of outdoor furniture, raised garden beds, rain collection barrels, and compost bins are made from the same thermally modified wood. 6
Our Facility ThermalWood Canada Inc. is located in Bathurst, on the northeastern tip of the Province of New Brunswick, Canada. The thermally modified wood production takes place in a 46,000 sq foot facility located in Bathurst Industrial Park. Current processing is done by means of a 30 cubic meter oven having a capacity of 16,000 board feet per batch. 1750 Connolly Avenue Bathurst, NB E2A 4W7 Canada Web Site: www.thermalwoodcanada.com Face Book: www.facebook.com/thermalwoodcanada Email: fawpltd@yahoo.ca or thermalwoodcanada@yahoo.ca Contacts: Bob Lennon Pierre Friolet Phone: 506.548.9126 506.548.9126 FAX: 506.548.2452 506.548.2452 Cell: 506.547.5092 506.226.1863 7