What makes Accoya® so durable?

Accoya® has earned the highest durability rating of any timber, lasting 50 years above ground and 25 years when submerged in freshwater. But what makes Accoya® so durable? In this blog, we take a closer look at the material and the applications it has in the manufacture of windows and doors.

The key features of Accoya®

Accoya® starts life as a fast-growing, sustainably sourced New Zealand or Radiata pine and then undergoes a process called acetylation (a wood modification technique). Acetylation replaces the water loving chemicals inside the wood such as cellulose, with acetic acid (the main component in vinegar). Acetic acid, unlike cellulose, is not hygroscopic, meaning it does not attract or hold water molecules from the surrounding environment, reducing the amount of moisture the timber will absorb and resulting in the following key features:

Dimensionally stable

Acetylation reduces swelling and shrinkage by 75% or more.

Outstanding durability

Acetylation also has an impact on the life of the timber; moulds and rots will not take root owing to the reduced water content of the material and insects are repelled as they can’t digest the wood. This has earned Accoya® Class 1 durability, surpassing even teak.

Perfect for coating

By providing a stable and durable foundation, Accoya® offers a superb substrate for coatings due to the lack of movement within the timber.

A sustainable material

Accoya® is sourced from well-managed forests recognised under the FSC® certification scheme. In addition, a vast amount of research has been carried out to assess the overall environmental credentials, including the Cradle to Cradle certification, of which Accoya® has earned the highest Gold accolade. You can find out more from the sustainability page on the Accoya® website – accoya.com/sustainability/

Why Accoya® for timber windows and doors?

As Accoya® is a durable, stable and easy to use timber it is perfect for harsh locations such as those close to the sea or where the windows and doors are exposed to the elements. To provide long life with low maintenance, at George Barnsdale we incorporate Accoya® components into our timber window and door designs. For example, in our sliding sash window design we use Accoya® for the frame linings, which traditionally have always been a vulnerable point.

To take a closer look at applications of Accoya® in the manufacture of timber windows and doors, visit our Pax House and Old Store case studies.

Old Store - wooden bifold doors
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