TREATMENT & PRESERVATION


Kiln Drying

It is most vital that all outside timbers are treated with a preservative to ensure they have a maximum life span. The first process for certain products is to be dried which takes place in our brand new kilning facility on site in Woodcote. Moisture measuring probes are carefully inserted into each batch of timber before the train enters the kiln. It is then heated and the air circulated on a computer controlled cycle for approximately 7 days until the timber has reached the necessary average moisture content.

Pressure Impregnation

The most effective timber treatments are applied using a vacuum pressure process. We have our own pressure impregnation plant and use one of the leading brands – ‘Wolmanit CX’ (please click on this link for more detailed product information). Treated timber will have a natural pale green colour but can by special arrangement be mixed with a brown dye if required. When dry it is completely harmless to plants and animals and safe to use.

The process involves a large steel cylindrical vessel into which the timber is placed. The door is closed and the air is withdrawn using a vacuum pump. Whilst under vacuum, the preservative fills the cylinder completely and is then pressurised forcing the liquid deep into the wood. Finally the preservative is drained off and a further vacuum is performed to remove the surface excesses. Once removed from the vessel the timber is taken to a draining area until dry enough to handle.


Why just "Treated" timber isn't good enough

Ask any timber merchant the question “…is it treated?” for any products you are purchasing designed to be in ground contact, and the answer will normally be “Yes”. That is usually the end of the conversation, but it shouldnt be – and here’s why –

Take a look at the two pine posts below. From the outside, both look the same (treated), but cut in half you can see the true picture of how long they are likely to last:

Figures (A) are green on the outside but completely untreated on the inside! And will last no more than a few years.

Figures (B) have treatment right through the sapwood, the most vulnerable areas, and well into the heartwood. Posts treated in this way should last for many years, at least 15-20 years in fact!

'Guarantees' are not Guaranteed!

What is the point of having a guarantee on an inferior product? They generally only relate to the replacement cost of the original post you bought.

Assuming you can prove you bought the defective posts from that supplier, you then have the far greater cost of re-installation that you will have to pick up yourself. And what will you be replacing it with…another inferior post!

How we do things differently

No compromise on quality of treatment

We set no limits on kilning times or amount of treatment chemical used, and specifically use the treatment chemical we believe to be THE BEST, not the cheapest! All our tagged posts are treated to (Hazard) Class 4 (if your posts are Class 3 or lower, they will NOT be suitable).

We control every part of the treatment process

From selecting the correct species and quality of timber used, the Kiln Drying process, and vacuum pressure treatment impregnation. We have extensive on site facilities to achieve this unlike the majority of our competitors.

We work closely with our chemical supplier

This allows us to run constant independant checks on our treatment quality and penetration. As well as on site, samples are sent to be analysed under laboratory conditions.

Each post individually tagged & recorded

Our posts are each clearly end tagged with our company name and a unique identification code for any future reference. Unlike some other tags and labels used in the industry, ours are designed NOT to deteriorate over time.

Choosing the right product

This checklist provides a comprehensive guide in selecting timbers you are using for in ground contact. If the answer to any of the questions is negative then they should be avoided:

What species is the Timber?

Redwoods – especially pines are regarded as only species suitable for in ground contact

Spruce / Firs
or non Redwoods

Has it been dried to a moisture content of below 28% before treatment?

Kiln drying the posts correctly reduces moisture content dramatically

Less treatment absorbed when the posts are wet

Has all the machining been done prior to treatment?

Machining exposes untreated areas

‘Brush on’ treatments are no match for vacuum impregnation

Is the treatment chemical used mixed to the correct concentration?

Correct mix should always be used

Weaker chemical is less effective

Has the Timber been treated to (Hazard) Class 4?

British Standard ensures post longevity

If answer is Hazard class 3 or below, timber is NOT suitable

Our Guarantee

“We guarantee that if you purchase posts with our named and numbered end tag, that each post is selected and processed to the standard required to achieve a minimum 15 year desired service life.”

We hope that this guarantee will give you the positive reassurance when choosing our products.