Can Accoya wood survive 2 years in the Thames?

Accoya fenders
Accoya fenders

The moment of truth: stripping back
the surface moss and slime to reveal
well-preserved Accoya wood

Spoiler alert: yes it can.

Accoya is timber that has been modified by a process called ‘acetylation’, which increases its durability, allowing it to resist rot and defy the elements.

In 2020, the Environment Agency tested a fender – an essential part of flood risk management – made out of Accoya at Duke Shore Wharf.

The timber was supplied by International Timber, who worked tirelessly to deliver the most eco-friendly solution, considering factors such as glue in the lamination process and potential effects on the environment.

Together, they worked with the Environment Agency team to understand the diverse wildlife inhabiting the area and to provide a suitable habitat for these organisms.

After a year on a Thames wharf wall…

After one year on the wall of the wharf the fender was inspected. There was no sign of any deterioration or delamination in the wood. And the level of colonisation by seaweeds and other marine life was at least as good as on the reclaimed hardwood fenders to which it was compared.

Nine further fenders

After a further year, the Environment Agency commissioned nine more fenders at Deptford Walls, Greenwich. To provide biodiversity benefits, the innovative design for the new fenders included habitable spaces for marine life.

Accoya fender

The fenders have a complex surface, with
deliberate nooks and crannies to encourage
macroinverterbrates and crustaceans

“The Thames water is a tough environment with brackish salt water and active marine organisms,” points out John Alexander, Group Director of Sales, Accsys. “These degrade all but the most durable wood types. It’s a real endurance test for a wood product.”

“The Accoya’s performance is in line with our expectations, after running sea trials of up to 13 years from the Pacific Ocean to the North Sea.”

The lack of toxic or plastic-based additives to Accoya is vital to its use in these environments, eliminating the risk of potential leaching into the water causing environmental or ecological harm.

This article is from issue 3 of Designing Timber magazine. Read more articles from Designing Timber here.