High Pressure Treatment provides an assured long term protection against all forms of wood decay and insect attack. This treatment process greatly extends the service life of a wide range of our timber products.
Treatments are carried out through a proven industrial high pressure vacuum process that forces the Twood preservative deep into the cellular structure of the timbers to give a highly effective and permanent protection.
The latest preservative is based on copper together with a combination of triazole biocides that together provide a robust protection against all decay organisms.
The treated timbers have an initial pale green colouration which slowly weathers in outdoor environments to a honey brown and eventually to a natural silver grey. This change in appearance does not diminish the overall long term preservative protection.
We do offer a treatment option where a rich brown colour can be added to the treatment if required.
All our high pressure treatments are carried out to meet the Use Class requirements required in BS 8417 – the industry’s code of practice for the preservative treatment of timber.
These Use Classes define the eventual end use of the timber in terms of its likely susceptibility of decay or insect attack. The higher the Use Class, the greater the degree of preservative protection is required.
The expected service lives of our high pressure treated timbers therefore vary depending upon their end use. For instance 15 years for external ground contact timbers to up to 60 years for internal construction timbers. Please ask us for further details on specific service life expectations.