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Accoya Troubleshooting Guide

A Quick Accoya Troubleshooting Guide

If you have selected Accoya wood for any renovations or structures in your home, you are benefiting from a product masterfully designed and engineered for low maintenance and an extended service life of over 50 years.

However, all materials exposed to exterior conditions are subject to natural degradation. Accoya is no exception. If you have used Accoya for your doors, windows or conservatories, for instance, you should expect the product to change over time.

We’ve put together a quick troubleshooting guide for when this happens, covering common Accoya problems to do with degradation or wear.

Accoya Paint Problems

If the coating on your Accoya wood is uneven or blotchy, there are two main possible causes. Either the coating was poorly applied or the product’s chemical formulation is incompatible with Accoya.

Before applying coating to any wood, it is vital to sand down the surface to prevent the coating from catching on uneven timber fibres. The wood’s moisture content must also be below 6% and sufficient time should be left between layers.

Accoya’s compatibility with commonly used coating products is part of its appeal, but it’s still important to double check that the chemical formulation of your paint or stain of choice won’t leve undesirable results. We highly recommend asking the advice of your joiner or supplier before selecting a coating.

To fix either of these Accoya paint problems, you can either get the coating re-done professionally or attempt it yourself if you have the right equipment by sanding the wood back down to a plain finish and starting over.


Due to its high resistance quality, Accoya is sometimes left uncoated, which leaves it subject to a progressive greying of the colour. This is as a result of UV exposure, and is perfectly natural. The rate at which this weathering occurs will vary according to the amount of UV the wood is receiving based on its positioning, surroundings, elevation and surface structure. It’s important to note that if the surface of the wood is partially shaded, such as by a tree of neighbouring property, the greying will be uneven.

You should be advised of this common Accoya problem when selecting the wood for your property, and be offered the option of applying a protective coating. If this wasn’t the case and you’re not happy with the new grey colour, you will be able to sand back the timber to a clean surface and apply a new coating with a brush.

Surface Growths

Research has shown that when compared to unmodified pine, Accoya has a similar or lesser rate of mould and yeast growth. However, as with all softwoods, there is still a high risk that surface growths will appear in damp areas. Such environmental factors, as well as temperature and sunlight, will inevitably impact levels of mould or yeast development.

Using a coating that is specifically formulated to resist to the growth of both blue stain and black spot mould growth is a key preventative measure, as is regular cleaning. It may be somewhat of a cliché, but prevention is always better than cure. Regularly wiping down the joinery to reduce the level of dirt contamination will significantly reduce the risk of unsightly mould growth.