Timber Pressure Treatment

The pressure treatment process adds extra moisture into the timber.

Timber is a naturally porous material and as such can absorb or release moisture depending on the weather conditions.

This uneven natural process is generally not detrimental and some movement in the timber is unavoidable. This can include splitting, warping & twisting. Larger section posts are more susceptible to these characteristics.

During hot weather fence panels & feather edge boards may become distorted. These should return to a more normal appearance during cooler, wetter weather.

These natural characteristics do not usually affect the structural performance or life expectancy of the timber.

We do not recommend using dark stains or paints as they attract heat which may cause additional movement in the timber during hot summers.

Treated timber that has been crosscut,notched or drilled must be retreated using a good quality endseal to reinstate the protective layer.

Our timber is pressure treated with preservative using the following process:

Timber Treatment Process

The majority of our timber is pressure treated with "Tanalith E" preservative.

Timber is treated to different Use Classes (UC) depending on what end use the Timber is intended for.

The Timber we stock is treated to UC 3 or 4.

  • UC 3 is for external use above ground
  • UC 4 is for external use in ground contact

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This is a text-based metric/imperial converter which means it has some limitations in the format in which it expects the data.

Things like 1' 6", 12ins or 2.3m are fine but don't mix imperial and metric formatting, for example 1.5ins (for an inch and a half) won't work, you can use 1 1/2 ins however.

The units that are recognised are as follows:

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    • yd, yds, yard, yards
    • ', ft, foot, feet
    • ", in, ins, inch, inches
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    • cm, cms, centimetres
    • mm, mms, millimetres