Tanalised / Pressure Treated Garden Timber

Earlier this week we received a review on one of our products, part of it was:

“The first thing I noticed was how badly it had been pressure treated with green splatters on a number of pieces”

I personally really hate a bad review, this was one but unfounded, we try our hardest to provide a top quality product with a top class service and will review everything that is said to improve where we can.Sometimes though it just comes down to understanding a product that you are buying and the expectations that match it.

This review has prompted me to write this quick post as from this statement it is clear that customers are not realising what tanalised timber actually is: I shall explain a little about it so people can gain more understanding of what you are buying and that there are no faults at all nor “badly” carried out.

Tanalisation / Pressure treatment are one of the same, it is the identical process and is carried out normally on pine timber for outside use as a rot protection:

Terms

The two terms used are describing exactly the same timber treatment:

  • Tanalised is actually a trademark, as is ‘Tanalith E’ which you will see sometimes.  This brand has been around since the 1940’s.
  • Pressure treatment is the process carried out using ‘Tanalith E’ or similar.

Process

The treatment process is carried out by placing the timber in a big tank.  The door is shut and a vacuum is created inside it.  Then the pressure treatment fluid is allowed to enter and is forced in the wood under the pressure.  It penetrates to a depth of a few millimeters.

Pressure Treatment process using 'tanalith' or similar

Ingredients

The main ingredient is copper with other chemicals added.  Copper is excellent for protection against rot and insects.  The other chemicals (Biocides) protect against other rot that the copper can’t such as ‘brown rot fungi’.  These substances are not harmful at all and can be used around animals and children.  Fish may be sensitive to it.

Rot Proofing of Timber 

It does exactly what it says and protects the timber from rot really well, internally they say about 60 years and externally about 30 years against any form of rot.  It’s pretty good stuff!

Promotional video explaining the Tanalisation process / Pressure Treatment

Please note after watching the process, it is in a huge tank under a vacuum, it cannot be at fault or ‘Badly’ done.

Limitations of tanalisation / Pressure Treatment

So now we understand how the process works, as the video explains, the timber will be:

  • An initial light green colour.
  • Weathers to a light honey brown.
  • Eventually to a natural silver grey.

This change of colour is not any indication of loss of preservative protection. Subsequent decorative finishes can be added to create the look you desire, you will see many examples of this across our website and catalogue.

We supply fixings that will have a comparable life to the timber for many of our products but please note if timber is cut, notched, sawn etc then a comparable treatment will need to be applied to carry on protecting the timber.

Perceived Faults in Pressure Treated / Tanalised Timber

Occasionally, a customer will perceive faults in the process without a full understand of it such as the above review. Some of these perceived faults are:

Formation of salts: 

With impregnated wood it may seem as if salts are formed on the surface of wood. It is actually resin that colours yellow/green due to the impregnation. These stains will vanish in time. This is an example and shows the ‘Splatters’ complained about in the review:

One of our fence panels displaying the formation of salts and "Splatters"

One of our fence panels displaying the formation of salts and “Splatters”

You can see from this picture green portions on the fence panel. This cannot be helped and is part of the pressure treatment process. You may see this on your new pergola, planter or gazebo, please expect this, it is completely normal.

Fungi and blue moulds:
Wood impregnated by boiler pressure induction will become very humid while being processed. As a result, the wood can be affected by mildew and fungi, especially during the warm seasons. These visual imperfections of the product will vanish or can otherwise easily be removed by hand.  Fungi do not affect the quality or strength of the wood.  Since wood can swell and shrink as a natural product, the dimensions listed in the catalogue and product pages can show small deviations.
This is an example from one of our show buildings. You can also see a small split in the timber which is also completely normal (more information: Splits in Timber is normal)
Blue mold and the formation of salt crystals.

Blue mold and the formation of salt crystals.

 All of these blooms, stains, salts etc can either be washed off or left, they will eventually go and is a standard feature of any timber that has been pressure treated. Our customer with the bad review went on to say:
“The pergola is up now and after fixing it and rubbing down the green splashes”
This was extremely worrying and I have advised him since, but, please do not “rub down” the ‘Splashes’! Doing so will remove the protection. Removal of resin bubbles is fine with a sharp knife but do not rub down the surface.
As we have learnt these are not a splash, these are the inherent properties of timber and the tanalisation process and are the cause of the copper ingredient reacting with the moisture and sap within the timber itself.
Here’s another example of a perceived fault:
Light bleaching after the tanalisation process.

Light bleaching after the tanalisation process.

I have added green lines on his product to highlight it more for you. You will notice there are some lighter lines. These lines will have been caused after the pressure treatment process and during storage. Light affects timber, it cannot be helped.
During storage certain parts may be covered due to packaging, positioning etc. Other parts are exposed to light. Light will start to react with the timber turning it first to brown and then to a silvery colour. Again this cannot be helped and should be expected.
After a few weeks all of the new structure will reach the same colour due to light exposure.
Of course you can add your own preferred colour to any tanalised timber. Tanalisation / Pressure treatment is of course only a rot proofing treatment is is NOT a decorative or weatherproof finish. Further treatment is highly recommended to stop cracks and splits, prevent warping and to maintain its good looks

Log Cabin Bargain Time of Year

These offers have finished 🙁

It’s that time of year and if you’re after a bargain the next few months is the time to buy your log cabin.  Everything has a season and ours is drawing to a close.  The nights are drawing in, Autumn followed by winter is not too far off, we may as well close shop until the Spring appears. But for you, if you’re canny and wiley, which perhaps you are now is a perfect time to find a log cabin, shed, garden building etc.  Now is the time of year for the garden industry that we start looking deeply at our stocks.  We don’t want to enter a quiet spell with full stock so we have to lose it.  Generally at near cost.  Bargain time for you! Take for instance the recent items we’ve added to our sales.  We have some pressure treated buildings still in stock that we really don’t want to carry so we’re offering them at hugely discounted prices. There’s only one of each, when they’re gone they will disappear and never be repeated. Here they are:

Heino pressure treated log cabin

Rome pressure treated log cabin

Pressure treated flat roof garage.

These really are a huge bargain.  If these log cabin suit your needs, please buy them quickly.  There’s only one of each!

There are several more than these shown, these are the highlights, have a wander though our log cabins category for many more substantial offers.

Pressure Treated or Tanalised Log Cabin

These two terms are used a lot in the garden industry.  Timber is often described as ‘tanalised’ or ‘pressure treated’.  Options are given with garden buildings, including our log cabins for them to be tanalised, others give them options of pressure treatment.

Terms

The two terms used are describing exactly the same timber treatment:

  • Tanalised is actually a trademark, as is ‘Tanalith E’ which you will see sometimes.  These brands have been around since the 1940’s.
  • Pressure treatmentt is the process carried out using ‘Tanalith E’ or similar.

Process

The treatment process is carried out by placing the timber in a big tank.  The door is shut and a vacuum is created inside it.  Then the pressure treatment fluid is allowed to enter and is forced in the wood under the pressure.  It penetrates to a depth of a few millimeters.

Pressure Treatment process using 'tanalith' or similar

Pressure Treatment process using ‘tanalith’ or similar

Ingredients

The main ingredient is copper with other chemicals added.  Copper is excellent for protection against rot and insects.  The other chemicals (Biocides) protect against other rot that the copper can’t such as ‘brown rot fungi’.  These substances are not harmful at all and can be used around animals and children.  Fish may be sensitive to it.

Rot Proofing of Timber 

It does exactly what it says and protects the timber from rot really well, internally they say about 60 years and externally about 30 years against any form of rot.  It’s pretty good stuff!

Limitations with Log Cabins

For the treatment of rot there is no real limitations, it works and works really well.  The main problem with pressure treatment of our log cabins is:

  • It is NOT a weatherproof treatment

You can of course not bother treating it, the cabin is not going to rot, well, not for thirty years or so but because it is not a weatherproof treatment you can expect the logs to absorb water which will result in rings and marks just like your coffee table at home with a hot mug of hot chocolate.

  •  It will discolour, it fades to a honey brown and eventually to a silvery grey.

Overtime it will discolour.  We can pressure treat / tanalise your log cabin in green or brown but the same appearance will result.  Normally over about five years.

This cabin was provided with Green pressure treatment:

Green Pressure Treated Log Cabin

Green Pressure Treated Log Cabin featuring the Sten Log Cabin

This one is done in brown tanalised pressure treatment:

Brown pressure treated log cabin

Brown pressure treated log cabin Featuring the Halvar Log Cabin

There isn’t a great deal between them but both will end up looking the same in a few years.

  • All of the wood is treated.

And this may be a problem for you.  When the logs are put into the vacuum tank there is no way to cover one side, all of it gets treated so what you see on the outside is what you see on the inside.

Summary

If Holland read what I’m about to say I may well get ‘questioned’ on it, but, I really hate pressure treated log cabins.  I try and steer my customers away from it.

In my mind as it’s not weather proofed you will still have to give your cabin a proper treatment, preferably with something expensive so you rarely have to repeat it.  If you want it to stay looking good you have to treat it.

Most people love the bright airiness of the cabin, do you really want to be staring at green or brown walls and ceiling, we go out of our way to source white wood over red wood so you have exactly that, an almost white interior, to spoil it with tanalisation just isn’t on really.

However, with that being said, other customers I will positively encourage such as this one:

Tanalised Log Cabin Garage

Tanalised Log Cabin Garage

Now here is a prime example when tanalisation / pressure treatment is excellent, it has a damp car stuck in it, it’s open to the elements internally.  Rot treatment makes sense! Here’s another one when I strongly recommend it:

Highly recommended to pressure treat this log cabin

Highly recommended to pressure treat this log cabin

Another prime example, I’d suggest to this customer to pressure treat the log cabin.  It’s constantly open to the elements internally and externally.  It makes sense.

All my other cabins, hmm, I don’t think it’s necessary, you’ve got to treat it anyway so why not put the money you would have spent on tanalisation into your treatment such as Sadolin, Sikkens or our excellent range of log cabin Paints and Log Cabin Stains designed for smooth planed pine wall logs.

I think it’s a bit like marmite, love it or hate it ….. up to you!