The long-term performance of pressure treated wood decks is being compromised by a failure to follow manufacturers installation instructions says the Timber Decking Association (TDA). According to the TDA, the need to re-seal cross cut ends, notches or borings made while installing treated wood is not being carried out in some sectors of the market. As a consequence, components are exposed unnecessarily to the risk of fungal decay resulting in a dramatically shortened service life. If a structural component is involved then the ongoing safe use of the deck becomes a major issue.

Steve Young, Director of the TDA says that market feedback indicates the practice is most widespread in the DIY and jobbing builder sectors where awareness of how to use pressure treated wood may not be as high as it is in the professional design and build sector.

Commenting on the poor installation practice he said:
“There is a widely held perception that if wood is green treated you can use it and abuse it in any situation. This is a myth. Wood protection is a controlled scientific process in which the treatment is tailored to the type of wood, the end use and the service life required. Like any other manufactured product, if treated wood is not used and installed properly it will not work as effectively as it should. Users who ignore manufacturers instructions really are inviting problems with all the time, trouble and expense involved in putting them right.”

The TDA is keen to remind deck builders that the only way a pressure treated component will deliver the service life expected is if the original treatment is not compromised:
“Sealing surfaces exposed by procedures like cross cutting maintains the integrity of the treatment” says Young who is also quick to point out that the practice also preserves any long term performance warranty given by a manufacturer: ”Quality pressure treated decking can come with a guarantee of 15 years or more but this is rendered invalid if end grain preserver is not used on cut ends.”
Cans of end grain preservative (also known as cut ends sealer) should be available for just a few pounds from the same outlets that supply pressure treated wood. End grain sealers that are accredited to the TDA’s DeckMark product quality assurance scheme are available from wood protection specialists like Arch, Osmose and ICI Cuprinol. More detailed information about good design and installation practice in general is available on the TDA web site: www.tda.org.uk

The TDA is working with other timber industry organisations like the Wood Protection Association and Wood For Good to help raise supply chain knowledge about specifying and installing pressure treated wood for decks and landscape joinery which includes access to a one-hour online training programme.

ENDS

Further information:

Contact Steve Young 01977 558147 director@tda.org.uk

Notes

1. The Timber Decking Association (TDA) is an independent technical and advisory organisation that sets the standard for materials and installation practices for decks and outdoor wood applications in the UK.

2. The Association operates the DeckMark™ quality assurance scheme for decking material manufacturers and contractors and keeps a register of businesses that it has assessed.

3. The TDA produces a range of publications aimed at both the professional designer and DIY enthusiast. Its web site www.tda.org.uk is packed with useful information about decks and the use of wood for permanent outdoor structures.

 

TDA URGES USERS OF PRESSURE TREATED WOOD TO COMPLY WITH MANUFACTURERS INSTALLATION INSTRUCTIONS.

Picture caption: Re-sealing cross cuts made on site ensures the long term, safe life of pressure treated wood. It also ensures any guarantee given by the manufacturer remains valid.