Thermal Modification thermal modif ThermalWood Canada prides itself for being a leader in the thermal modification manufacturing of wood products. Our in-house thermal modification process has been studied for many years, yet is simple at the base. Using our specially designed kiln, the wood is heated at a precise temperature, essentially cooking the lumber. This process changes the characteristics of the wood. Notable advantages include: Improved dimensional stability Eliminates the risk of decay and damage caused by insects The high heat chemically transforms sugars in the wood. This makes the wood unattractive to potentially harmful insects, and acts as a barrier against decay caused by humidity and other water damage. Uniform darker coloration throughout the thickness of the lumber This makes it a great choice for outdoor or indoor uses where high humidity is present.