Door Industry Journal - Summer 2016

Also online at: www.dijonline.co.uk 62 THE door industry journal summer 2016 garage doors feature Woodrite – What is Accoya®? Since adding Accoya® to its range of timbers in the form of the Thetford range of garage doors, Woodrite has seen sales steadily rising. The eye-catching feature is the 10-year warranty on finish. What is it about Accoya® that makes this possible and what else has the wood to offer? Accoya® wood is the result of decades of research and development that has brought together a long- established, extensively proven wood modification technique and leading-edge patented technology – acetylation to create a high performance wood, ideal for outdoor use. Accoya® has properties that match or exceed those of the best tropical hardwoods and treated woods, yet is manufactured using wood from sustainable sources. Why does wood rot? The physical properties of any material are determined by its chemical structure. Wood contains an abundance of chemical groups called “free hydroxyls”. Free hydroxyl groups absorb and release water according to changes in the climatic conditions to which the wood is exposed. This is the main reason why wood swells and shrinks. It is also believed that the digestion of wood by enzymes initiates at the free hydroxyl sites – which is one of the principal reasons why wood is prone to decay. What is Acetylation? Acetylation effectively changes the free hydroxyls within the wood into acetyl groups. This is done by reacting the wood with acetic anhydride, which comes from acetic acid (vinegar when in dilute form). Acetyl groups are already naturally present in all wood species. This means that the manufacturing process adds nothing into the wood that does not already occur within it. The end product, Accoya® wood, does not add toxins to the environment. The effect of altering