Accoya®: a decade of durability

The two tests

Architectural designer, Gordon Aitken, chose Accoya to clad his Scottish home in 2006, due to its many preferential credentials: “I initially chose Accoya due to its exceptional durability and 50-year above ground guarantee, as well as being impressed by its environmental credentials and aesthetic qualities.”

Gordon’s home was the very first in the world to be clad in Accoya and its location in a harsh, northern climate would be an interesting test for the modified wood product.

At the very same time, the Timber Research and Development Association (TRADA) commenced a test-rig research project to assess the performance of Accoya over a period of 10 years when exposed to natural weathering.

Gordon’s Fife home results

Fast-forward to 2016 and Gordon Aitken’s home has endured no shortage of rain, sleet, snow, extreme temperatures and piercing sun. His 30m² of Accoya cladding is present on both north and south facing facades, coated with a translucent Sikkens protective coating system.

“Since it was installed in 2006, we have experienced a lot of harsh weather conditions, with the north façade being particularly exposed. But in the last 10 years, I have only maintained the cladding once by cleaning it with a mild soapy water solution, restoring it to “as new” appearance,” says Gordon.

10 years ago (left) and now (right)

And TRADA’s

It seems that TRADA experienced similar success for Accoya from its test-rig research. A natural test exposure facility was set up at TRADA’s HQ, using Accoya as vertical cladding, coating it in a Sikkens high-build opaque and medium-build semi-translucent coating system. After 10 years’ exposure to natural weathering, observational evidence reported that regardless of coating used, the cladding remained in excellent condition.

An extract of the report said: “Neither rig showed any evidence of any coating breakdown or substrate instability with the possible exception of the rig coated with the semi-translucent woodstain where slight fissuring around the nail heads was seen to have developed on the north facing aspect…arguably the greatest significance of the findings resides in the fact that the Sikkens coating, in both cases, showed no requirement for maintenance after 10 years.”

In fact, the report concluded that: “the results of the test have shown that the use of Accoya as a substrate for exterior cladding systems can achieve significant benefits in terms of longer performance and reduced maintenance to typical lifetime expectations when conventional softwoods are used.”

Accoya is manufactured by Accsys Technologies and proves popular with both architects and joiners. It has a variety of uses that range from windows and doors, to external cladding, decking and other structural projects. Using only wood sourced from FSC® certified sustainable forests and Cradle to Cradle Gold certified, Accoya also maintains excellent environmental credentials, coupled with its now proven durability accolades.