The generic term for Accoya is acetylated wood. Acetylated wood had been studied by wood scientists for many decades before Accoya came to the market. Consequently, there are examples of long term trials where acetylated wood has demonstrated its exceptional performance.
In addition, there is a standard European test for the durability (rot resistance) of timber by which it is possible to directly compare the durability of Accoya with that of any other timber and since we know what to expect from the other timbers we can conclude what to expect from Accoya. Both the BRE (Building Research Establishment) and TRADA (the UK’s leading independent timber research association) support the claims made about the durability of Accoya and therefore we can offer the unrivalled 50 year warranty.