Most of the fencing products you buy will have been pressure treated, a process which is also known as a vacuum impregnation process. The long-used preservative chemical CCA was removed from use in the EU in 2004 following European legislation. The replacement for it needs a more thorough pressure treatment process, as higher concentrations and higher quantities are needed to penetrate the timber so that they are effective.
This isn’t particularly easy, but while many operations are still not using the correct processes for effective timber treatment to achieve the required chemical loadings, we certainly are!
In fact, under the banner of our PermaTimber brand, our products have been recognised nationally for the innovation and thorough processes that we have developed over time in order to ensure the longevity and durability of your fence posts.
We are so confident in the PermaTimber products that we also give a 15 year guarantee along with our fence posts.
So what goes into the PermaTimber process to differentiate it from lesser methods?
We ensure our chemical solutions are mixed to the right strength, and these solutions are monitored and audited constantly to ensure that they’re always that way.
We consider the species of the timber and run a pressure vacuum cycle appropriate to that species, as some timbers are more impermeable than others, rather than just running a generic cycle.
As a result, our treatment process can take up to twice as long as some other treaters who are not following the correct procedure. We want to make sure we provide the best product at every stage of production.
Preparing the timber:
Next, the timber is prepared for treatment. This could mean certain species are kilned in order to remove the natural moisture of the timber prior to treatment. This would then make way for the preservative to penetrate the timber. Alternatively, with some of the impermeable timbers we mechanically incise them, with the resultant slits aiding penetration of the chemical.
As Walford has WPA Benchmark certification, the entire process is audited on a regular basis to make sure we maintain our high standards. Our chemical supplier carries out even more frequent internal audits to monitor aspects such as solution strengths, uptakes, penetration depth and so on.
Questions you should ask:
Are your posts pressure treated? If so, are they treated to Use Class 4? (Ground contact specification for B.S. 8417.)
Do your posts come with a guarantee?
Are your posts also WPA Benchmark approved? (The UK quality treatment scheme.)
Are your posts also FSC Certified? (Proof that they are from a sustainable source.)
If your timber supplier is able to answer yes to those questions, then you have found a quality supplier.
Additional information can be found here: