What is Tanalised Timber?

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Using timber isn’t just about cutting down trees and using raw product, timber requires treatment in order to get the best from it and guarantee longevity from the products that you’re manufacturing. Picture any forest or wood, fallen trees will eventually begin to rot and decay, this is exactly what the tanalised wood is designed to avoid.

At Power Sheds, we’re proud to offer high-quality timber that stands the test of time, and all our shed base kits are made from pressure-treated tanalised timber. Let’s take a look at exactly what tanalised timber is and the effects that the process has on wood.



Tanalised Timber: What is it?


Tanalised timber, often known as pressure-treated, is a timber that has been impregnated with a preservative solution by using an industrial vessel that does this under high vacuum pressure. Amongst other things, one of the treatments used on the timber is called Tanalith E and is used because it stops the wood from rotting and has proven qualities that work to stop fungal decay and insect ingress.

When it comes to making shed bases, using tanalised timber means that the base, which is exposed to much damper conditions and regular insect attacks than other areas of the shed, will last a lot longer and not begin to suffer when it comes to quality and structural integrity.


How Does Tanalised Timber Treatment Work?

Tanalised timber treatment is carried out at high pressure and must be done on an industrial scale. The timber is placed into a large container on an industrial scale, at this point it is completely flooded and submerged with the tanalising wood preservative. Once the timber is flooded, the whole container is put under high hydraulic pressure, which forces the preservative into the timber and ensures it’s effectively treated. The final step is to relieve the pressure in the tank and break the vacuum, this allows the low pressure in the timber to draw in the preservative.

This process means that tanalised timber can only be done on a large scale and isn’t something that smaller manufacturers, or even those at home, can do to their timber. Once the treatment is finished, the tanalised timber will have a slight green colour to it.


A shed base made using tanalised timber


Why Don’t We Make Completely Tanalised Sheds?

As mentioned before, tanalised timber is perfect for use on shed bases thanks to its increased protection against wet conditions and attack from insects. However, this doesn’t necessarily mean that it’s the right choice of treatment for the entire shed. As tanalised timber has to be made on such a large scale, it means that the wood is not ideal for being cut down to size for a shed. Once tanalised timber is cut down the ends of the wood are exposed to the elements and it’s no longer as well protected as it was before.

These ends are the easiest part of the timber for water to get into. Some companies (although very few) paint the ends green to hide this lack of treatment, they may also paint the facias (not with a preserver) so they are the same green colour. This all means that important parts of the shed are practically untreated, however, the label ‘pressure treated’ is added to sound good to the purchaser.

At Power Sheds, we choose not to use tanalised timber in our shed manufacturing. Instead, all of the timber we used on our sheds is high-grade Scandinavian wood that has been dip treated in preservative to help sustain its lifespan. From there, you can paint your shed and add a preservative annually to help keep it in great condition.


How Long Will Tanalised Timber Last in the Ground?

As a rule, the outside of the tanalised timber should last for around 30 years, with the inside having an expected lifespan of around 60 years. The tanalised timber treatment process is special in that it doesn’t require any regular upkeep, unlike many wood treatments that may need a new coat annually.

As with any wood product, the location and exposure to elements will have a major deciding factor on how long it stays rot-free and in good condition. You can, of course, also choose to apply paint or any extra treatment to the wood in this time.


At Power Sheds, we believe in using the best possible materials in the manufacture of our sheds. So, whether you’re purchasing a shed, a log cabin or tanalised timber shed base, our goal is to make sure your shed looks great and stays in the best possible condition for many years.