Virtually all wood preserving treatments today work by impregnating toxic chemicals (such as arsenic, oils, ammonia or metal compounds) into the cell walls of the wood. This works to fill the voids within the wood but this doesn’t change the underlying chemistry. The toxicity of such products also have negative environmental implications during the serviceable life of the wood as well as during its disposal.

As an alternative, Accoya alters the wood’s structure to the core, creating an inhospitable environment and helping to control unwanted organisms, such as bacteria, viruses and fungi. The main alternative non-toxic preservative treatment to Accoya’s acetylation is “thermal modification”, a process which works by breaking down the edible components of the wood. However, the process both discolours and weakens the wood, rendering it unsuitable for many uses.

The Accoya production process does not weaken the original wood – in fact, its hardness is slightly improved and its bending strength uncompromised. Indeed, no modification process exists which offers the performance benefits and retained physical properties of Accoya.