Tree of the Month – Radiata Pine

This month we are looking at Radiata Pine – a tree which on the surface doesn’t seem to offer anything special – however its ability to be modified gives it amazing new qualities and for this reason you shouldn’t underestimate the potential of Radiata Pine.

The world’s most planted pine

Although Radiata Pine is native to California, it is heavily planted in Australia and New Zealand, making up over a quarter of Tasmania’s timber plantations and 89% of New Zealand’s plantations forests. In fact, it is now thought to be the world’s most widely planted pine.

Radiata Pine is:

  • A coniferous evergreen tree which is widely used in the construction and decorative industries
  • The sapwood is typically white to pale yellow, with a straight grain
  • 33% heavier than dried Western Red Cedar, and owing to its brittle nature is not as effective as Douglas Fir when it comes to load bearing
  • Fine textured, low in density and relatively soft
  • Its low density makes it easy to dry – apart from the core
  • A fast-growing tree – just 28 years to harvest
  • Widely used in the construction industry because it is easy to work with
  • A softwood in origin, however its capacity for taking on preservatives and to be chemically modified has made it a highly sought-after product

A wolf in sheep’s clothing

Radiata Pine’s superior ability to take on preservatives has made it a perfect candidate for modification, which means that under the right process this quick-growing softwood can take on the properties of slow-growing tropical hardwoods. And, with the world looking to bring a halt to rapid deforestation and more sustainable timber production methods, this modification of Radiata Pine has brought about a long-awaited solution to a problem of global significance.

A long history of modification

Radiata Pine has a long history of being modified, with the process of being tanalised introduced in the 1940s to make the product strong enough to use in-ground. Whilst this treatment process does prevent rotting, it does not stop natural movement in the wood. The use of copper in this treatment process is also associated with giving the product a green colouring, while concerns about the health implications of some forms of modification have seen certain methods banned in some countries.

Transforming ordinary into extraordinary

However, in recent years, British company, Accsys Technology has come up with a new modification process called ‘acetylation’, which transforms softwoods such as Radiata pine into a superior product that surpasses the qualities of stability and durability in other slow-growing hardwoods, and without incurring the environmental costs.


  • Acetylation is the process whereby water-attracting hydroxyl elements are drawn out of the wood and replaced with something else (known as acetyl groups).
  • This near-enough stops the cells in the wood from absorbing water, making it dimensionally stable and rot and insect-proof too.
  • This makes Radiata Pine (in its changed form) three times more stable than conventional timber and more long-lasting. It has a class-1 durability rating and a minimal service life of 70 years according to the Timber Research and Development Association.

And if you’re thinking you need to get some of this wonder wood, then the product you’re looking for is called Accoya® – which is somewhat catchier than modified acetylated Radiata Pine.

  • Accoya®  is made from New Zealand Radiata Pine, because they trim the branches so there are no knots.

Westbury – number one fan of modified Radiata Pine

Accoya® outperforms cedar, teak and many other treated softwoods and hardwoods and it is non-toxic and 100% recyclable. Because the Radiata Pine is so fast growing, this means Accoya® can be created from well-managed sustainable sources rather than tropical forests that leave behind a trail of deforestation. Accoya® also remains CO2 negative over its full lifecycle. It also boasts superior thermal insulation giving it environmental advantages even when in situ.

You won’t be surprised to find out that this is the timber that we use here at Westbury. Our garden rooms are made Accoya® which means they won’t move, they won’t warp and they won’t crack.

When combined with our high-tech paint system, which makes the timber impermeable to the elements, our Accoya® products can last a lifetime and because the timber is stable, users won’t even have to repaint their products for 10+ years.

With the product guaranteed to last a lifetime, this means that you only need to buy once so you won’t be wasting the planet’s finite resources or your own – and this is a big part of what we’re about at Westbury.

So, with just a bit of science and modification, the bad boy in timber just became the best boy in timber.