There are a number of considerations for preservative treating timber deck boards.
All commercial anti-slip timber deck boards should be preservative treated to protect against insect attack, rot and decay. Deck boards installed in areas used for access and escape routes may also need to be treated with a fire retardant.
You also need to consider which ‘Use Class’ should be specified, depending on the application of the decking. The two classes associated with outdoor timber decking are Use Class 3 or Use Class 4. Use Class 3 is the most common. This is described as ‘Above ground contact, exterior use’. Use Class 4 applies to ‘In ground contact or fresh water, permanently exposed to wetting’.
A less common thing to consider is if planters or hot tubs are going to be situated on the decking, then you should treat to Use Class 4. Such post design features are not often considered, but items such as these will cause regular in ground contact or water contact on the decking, leading to eventual failure of the boards.
WPA Benchmark is a quality scheme that gets right to the heart of treated wood fitness for purpose. It provides independent reassurance that timber has been treated correctly for its end-use and will deliver a service life in line with BS 8417 specifications.
All Marley Eternit deck boards are now treated within the Marley Eternit Benchmark scheme, carry an additional 40 year warrantee and are fully labelled in accordance to the new European Biocides regulations.
Operated by the Wood Protection Association, the UK authority on wood preservation, WPA Benchmark has the credibility and market relevance essential to build buyer confidence in treated wood performance.