Wood Protection – How to Protect Wood/Timber from the Elements?
When timber cladding is installed on a building it requires high-quality treatment to protect it from the elements.
How Can You Protect Wood/Timber from the Elements?
Untreated wood will naturally dry out and age over time, although some species will degrade faster than others. From the moment the wood is cut from the tree this gradual process begins. Depending on exposure these effects can vary over time.
To protect and preserve your timber cladding for years to come it is important that you take steps to treat and maintain the wood.
One method of protecting the timber is to cover it in a thick layer of paint. Although this treatment will preserve and protect the wood underneath, it will also spoil the natural look of the timber meaning it’s less astatically pleasing.
We suggest a different method of protecting your timber cladding, pressure treatment.
What is Pressure Treatment?
Pressure treatment is the most effective way of protecting timber used in external applications. The process involves placing the timber inside a high pressure vacuum cylinder where specialised chemicals are then forced deep into the wood. The length of time and amount of pressure is determined by what kind of treatment the wood requires (certain species will also allow more penetration than others).
What are the Benefits of Pressure Treating Timber?
This process makes the timber extremely more durable meaning it will last much longer than untreated wood. Not only does the treatment help to protect the wood from rot and termite damage but it also protects against fungal decay.
Situations Where Timber Should be Pressure Treated
Timber is categorised into different hazard classes (1-4) which illustrate their likelihood of rot and therefore the type of treatment they require. Wood that will be used inside is unlikely to get wet or rot so thus won’t need much treatment. Wood used externally, however, such as cladding, fence posts and decking, is likely to be getting wet and damp so will need the top-level pressure treatment.
Some species of timber require pressure treating in different ways. Remember that pressure treatment isn’t just coating the surface, the treatment actually penetrates the timber and as different species have different cell structures, some species are more permeable to preservative treatment than others. The higher the hazard class, the more treatment is required to penetrate the timber.
The Structure of Timber
A piece of timber is made up of two types of wood: sapwood and heartwood.
- Sapwood is the living part of the tree and has cells which transport the water up and down the trunk of the tree. This is found on the outer most part of the trunk beneath the bark. As it is living, the sapwood contains food stuffs which are attractive to insects and fungal decay.
- Heartwood is the dead part of the tree with closed cells. This is found in the centre of the trunk and as it doesn’t contain food stuffs, it is not attractive to insects or fungal decay.
When we pressure treat timber, we treat the sapwood rather than the heartwood. This is because we need to prevent the sapwood’s condition from deteriorating and because it has open cells which can accept the treatment. We don’t treat the heartwood as it is naturally durable and because its cells are dead meaning it won’t accept the treatment.
Timber Selection
When selecting a species for a particular end use, we must therefore consider the following:
- How easy it is to treat the sapwood.
- How durable the heartwood is.
Pressure Treatment with NORclad
Here at NORclad we supply a wide range of beautiful timber cladding and façade solutions, and when pressure treating our wood we use a revolutionary new wood preserving process. This process impregnates wood cladding with a blend of preservative and Brunnea pigment, meaning that the wood will hold its colour for longer with little/no maintenance required. Our pressure treated wood also comes with a 30-year warranty against rot and fungal decay.
Contact our team today to find out more.
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