Serious issues and concerns identified – our research casts doubt on the suitability of chemically treated wooden posts in ground contact
Why did we run this survey?
We have now finalised the results of the AFI survey on wooden posts and the effectiveness of the treatment since CCA use was suspended by the European Union back in 2006. The survey was intended to establish a current view of the life expectancy of chemically treated timber posts compared to the 15-year life suggested for materials treated to the UC4 specification (BS8417) and the impact on the industry of failures to reach this life expectancy.
This action was taken after discussions with the Wood Protection Association (WPA) on the possibility of introducing a guarantee scheme which would compensate contractors in full if posts failed prematurely, rather than just the cost of replacement posts.
The survey received responses from across the industry, mostly from fencing contractors. Almost three quarters of the responses were from organisations where more than half of their business is timber in ground contact.
Over 75% of the respondents had experienced failures between 2006 and 2012 with the figure rising to 90% for failures since 2012. These failures are having a negative impact of all the businesses surveyed with failures varying from at least one per year up to four or more per year, for 60% of those surveyed.
The majority of users are currently using timber with alternative treatments/species and looking to use alternatives to wooden posts where they can.
The UC4 specification (BS8417) is well recognised by the industry with almost three quarters of those responding using UC4 exclusively for wood in ground contact. There is no doubt that the industry has lost faith in the ability of suppliers to supply posts which can be relied upon to last 15 years in ground contact – 90% of the replies confirmed this.
The responses indicated that if there was a guarantee scheme available the vast majority of the industry would be behind it.
There was a general view that current treatments do not provide a consistent performance in terms of life expectancy and that, as a consequence, chemically treated wooden posts are not living up to suppliers guarantees for in ground contact. The 15-year life suggested by UC4 may well be what the treatment companies wish to provide but, in practice, it fails all too often.
Although our survey is now closed, we encourage anyone working with timber to continue to advise us of issues.