Timber Treatment – ACQ what is it and the benefits

Here at George Hill in Oldham we have an onsite treatment plant, which therefore allows us to treat any timber required. Our trade customers such as joiners, carpenters and builders all know the benefits of using treated wood. ACQ is one of the treatment methods we provide. However, ACQ is a technical term and jargon so weโ€™ll explain more.

ACQ – Alkaline Copper Quat

ACQ treated timber is a copper plus quat system that provides protection to wood against decay, rot and insect attack without the use of arsenic and chromium. Quats are regularly used in disinfectants and cleaners and are biodegradable in soil. ACQ treated wood does not contain hazardous chemicals and is therefore regarded as a safe to use.



ACQ treated wood can be used for many projects and is regularly recommended for Fencing & Fence Posts, Decking, Outdoor Furniture such as Tables and Benches, Gazebos. It is recommended where long-term protection against decay, rot and insects is a priority.ย 20130523_134726



Of course treated timber will last much longer than untreated wood. It can be a false economy to buy cheaper untreated timber. Without treatment against the elements wood can rot very quickly and may even need replacing after as little as 12 months. Oil based treatments and stain will provide protection and offer the choice of different colours and finishes but takes time to apply and should be done in dry conditions. Therefore buying treated timber means the job can be finished quicker.


Painting and Staining

ACQ treated timber can be stained or painted to suit your choice of colour scheme or theme. Good quality oil based paints and stains are best. Water repelling covering can be used to improve the weathering performance over a period of time. It is, however, important that the timber is dry and clean prior to application . Left untreated, or with clear treatment, ACQ will initially weather to a natural brown color and turn grey with long-term exposure to the elements and sun. We recommend using galvanized or stainless screws and nails used with ACQ.ย DEEO2500


George Hill on-site Treatments

We can treat timber as a stand-alone service too. Treatment is carried out by ourselves onsite at our Oldham Sawmill Site (off Ashton Road A672). Other trade and Timber Merchants use our treatment services too. However, it can save money and time if you order pre-treated timber from us.

To order ACQ treated timber or if you have wood you need treating, feel free to contact us for more information.






Decking Screws

Timber and Building Merchants

George Hill is a leading independent timber merchant and building supplies provider in the North West, with branches in Oldham, Manchester, Bolton and Nelson. Founded in 1919 weโ€™re family run, and have been for 99 years.

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