Understanding Timber

Due to the nature of timber, the appearance of wood grain and number of visible knots may vary. Knots embedded in the wood are a common feature of timber products and are part of the material’s rustic charm. Dead knots are rotten and usually black – this is unacceptable.

Each tree that gets turned into timber to use for our products is unique in colour, shape, density and wood grain – these unique characteristics are retained after processing. Where timber varies in density, it absorbs the chemical preservatives used in pressure treating differently, potentially resulting in colour variations. Over time, these colour variations will fade as your timber product is exposed to sunlight. As timber ages, it takes on a silvery colour.

Our timber is pressure treated with chemicals that enable us to protect our products from environmental conditions as much as possible and offer a 20-year anti-rot guarantee. This process pushes chemical preservatives into the wood, to help protect it from the elements once it starts its life as an outdoor product. This treatment commonly leads to green and white spots appearing on the surface of the wood, but these can be brushed off easily.

Resin can appear in spots or streaks on treated timber products – this is a common occurrence as the wood changes in volume and thickness during storage and processing. Resin also comes to the surface of the wood in warm weather and when placed in direct sunlight. To remove resin, careful scrape the surface of the product, or use turpentine.

Blue-stain mould and discolouration is especially common during warmer periods, although pressure treatment stops serious fungal infestation. During storage of freshly pressure-treated timber, there may be some occurrences of mould stain caused by the fungus. These stains are no cause for concern and can be wiped off or left to gradually disappear on their own when exposed to the elements. Black mould is unacceptable and below our quality standards.

Rough spots can occasionally be caused whilst the timber is being machined during processing. Whilst the wood is sawed, planed and milled we do everything possible to avoid damaging the wood, although slight fraying is unavoidable during processes such as crosscutting and rounding over posts.

Also known as ‘wood movement’, shakes are splits that are caused by the natural expanding and retracting of the timber as moisture reacts with its core as it gradually absorbs and releases moisture from the air.

Warping occurs due to swelling and shrinking – as wood varies in density and texture as it is exposed to moisture, this is not uniform and cannot be prevented against. Warping and cracks as a result are natural, and do not affect the structural characteristics or strength of the timber. You can counteract warping by watering your timber products.