We’ve said it before – one piece of preservative treated timber can look and feel very much like another. But those in the industry know the level of protection offered can differ, depending on the treatment process and the end use application the wood is treated for.

Performance failure of incorrectly specified or badly treated timber is giving the timber sector a bad reputation – especially in the structural and higher risk timber sectors – opening the door for competitive materials to get the upper hand.

The Wood Protection Association (WPA) has established through market research and experience of its members, that the problem for treated timber buyers and specifiers is two-fold.

  • Knowing what to ask for: being familiar with the Use Class (UC) system of timber treatment;
  • Getting what they ask for: being assured the purchased timber is treated correctly for its end use.

Through the work of the WPA, its members and industry partners, including Timber Development UK (TDUK), significant progress around the first point – treatment Use Class awareness – has been made over the past three years, but all parties recognise there is still more to do. With regards to the second point, there is a plan.


Independent, third-party accreditation is of vital importance, it raises buyer confidence and gives added assurance of fit-for-purpose goods and services – treated timber is no different. This has driven the WPA’s work of trying to enlist as many UK and overseas timber treaters, onto the WPA Benchmark Quality Approved Treated Wood Scheme – you don’t need to be a member of the WPA to be accredited.

WPA Benchmark certification is awarded to treaters who demonstrate their quality systems and processes are reliable and robust. Compliance involves auditing every aspect of the treatment process. It covers an assessment of the incoming wood quality, moisture content, preservative management, treatment cycles and measurement of results. Sample analysis of treated products is required to demonstrate compliance with the preservative penetration and retention requirements of the scheme (Use Class 4 products).


Commenting on the actions to raise awareness of WPA Benchmark, scheme administrator Neil Ryan said: “Promotional advertising and editorial articles are consistently appearing in trade publications. We’ve also worked on our website so visitors can go directly from every page to our list of accredited WPA Benchmark Approved Treaters – all of which have website links to each business site.”

Verified businesses are increasingly using their WPA Benchmark quality achievement branding in their own marketing collateral which, said Mr Ryan, is essential in elevating accreditation status and getting the Scheme recognised more widely.