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3 Types of Chemical Treatments Used to Protect Timber Fences

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Timber fencing is universally popular for it's natural looks, affordability, and the way the material blends with the rest of the garden. However unlike other fencing materials, timber fencing is also attractive to subterranean termites serving as a food source. Luckily to prevent termite and wood-borer damage, as  well as rot and fungal growth, homeowners building timber fences use a number of different chemical treatments that help to protect their fences. Three of the most common chemical preservatives used are explained in more detail below.

1. Light Organic Solvent Preservatives (LOSPS)

Light organic solvent preservatives (LOSP) products are often used for fence palings in low risk termite areas, but typically only for sections of timber that are above the ground. Radiata Pine and Western Red Cedar are common species that are treated with LOSP products.

LOSP products contain fungicides and insecticides that are impregnated into the timber product. These treatments are usually colourless, however green and brown stained LOSP timber products are available.

2. Copper Chrome Arsenics (CCA's)

CCA treated timber products are preserved using a combination of chromium copper and arsenics.  Used since the 1930s, the chromium chemical locks the arsenic and copper into the timber, helping to prevent these from leaching out.

Because of their toxic nature, CCA treated timber are recommended for use only in landscaping and residential fencing applications. In a timber fence, the CCA treated timber will most likely be used for in ground fence posts. Because of the potentially harmful and volatile chemicals there are a number of safety recommendations for those who work with CCA timbers.

3. Alkaline Copper Quaternary (ACQ's)

Used as a greener alternative to CCA's, ACQ preservatives are water based treatments containing fungicides, insecticides, copper and ammonium compounds and used to repel insects including borers and termites, and prevent fungal growth.

The strength of the ACQ chemical treatment used will depend on the level of moisture and environmental conditions where the timber fence is being built. It's important to remember that ACQ treatments accelerate corrosion of metal fastenings used to secure timber sections, so it's important to plan for this by using anti corrosive fastening products like stainless steel. ACQ's products can also give timber a green tinge, however this can be overcome if pigments are used during the treating process.

As you can see, there are a number of different treatments that can be used to protect your timber fence from succumbing to termites and the elements. Your timber fence contractor (such as Noble Works Australia) will be able to recommend specific timber treatments based on the type of fence being built, it's location and the environmental and climatic factors where the fence will be built.