Welcome to the world of Accoya®

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Sustainable high performance wood

Ideal for windows, doors, cladding, decking and many more applications

Accoya® wood is a high performance wood. Created from sustainably-sourced wood, Accoya® undergoes a proprietary, non-toxic acetylation process that permanently modifies the wood to the core.

The result: an environmentally friendly solid wood with durability, dimensional stability and beauty that matches or exceeds even the best tropic hardwood.

Accoya® wood is sourced from sustainable sources, including FSC® and has class leading environmental credentials such as Cradle to Cradle™ Gold certification by the highly prestigious McDonough Braungart Design Chemistry (MBDC) organization.

Accoya® wood is perfect for demanding applications such as windows and doors, where it is important that tolerances are tight yet regardless of the conditions, they open year round. Accoya® is perfect for siding where wood’s natural beauty is desired, but sustainability and high performance are of the utmost importance. In decking, where it is important that boards do not warp, twist, bow split, Accoya® is up to the challenge.

Italian Alpine Villa

Features & Benefits

Extensive laboratory and field testing by leading institutes around the world (including in New Zealand, USA, UK, Sweden, Malaysia, Indonesia, the Netherlands and Japan) has shown the performance of acetylated wood to be extremely reliable. Accoya® wood has been thoroughly tested for dimensional stability, durability, paint retention and in-ground conditions to ensure optimal performance. Indeed, it is so reliable that for many years it has been – and continues to be – used by scientists as the benchmark against which other treatments and modifications are measured.

Key Features

Dimensionally Stable
  • Swelling and shrinkage reduced by 75% or more
  • Doors and windows open effortlessly year round
  • Reduced maintenance costs
Outstanding Durability
  • Lasting 50 years above ground, 25 years in ground/freshwater
  • Class 1 durability, surpassing
Perfect for Coating
  • Improved stability means coatings last up to two times longer
  • Easier to coat, less preparation and sanding required

Features & Benefits

Naturally Insulating
  • Offers improved insulation in comparison with commonly used hardwood and softwood species
  • Ideal for applications where energy conservation is important
Excellent Machinability
  • Easy to machine and process
  • No special tools are required
Insect Barrier
  • Indigestible to a wide range of insects, including termites
  • Greatly reduced vulnerability
Consistent Quality Throughout
  • Consistent, measurable modification quality from surface to core
  • No need to apply chemical preservatives when cut or planed
Naturally Beautiful Wood
  • Process does not compromise the wood’s natural beauty
From sustainable sources
  • From FSC, PEFC and other regionally certified woods
  • Naturally renewable
Retained Strength & Hardness
  • The process does not compromise the wood’s strength
  • Hardness is increased
  • High strength to weight ratio makes it suitable for challenging applications
Non-toxic & Recyclable
  • Protects the environment from the harmful effects of common treatments
  • May be safely reused, recycled and incinerated
Barefoot Friendly
  • Ideal for all decking situations in extreme temperatures
  • Low thermal gain
  • Splinters are much less than other wood species when used for decking

Outstanding Durability

Accoya is already inspiring architects, designers, specifiers and individuals around the world with its outstanding qualities and the possibilities it offers for using wood in exterior applications.

Class 1 Durability

Cellulose is a major structural ingredient of wood but it is also a major food source for several different insects and decay fungi and makes a great shelter for others, too. Rot causes wood to degrade – particularly when it is used outdoors and exposed to moisture – limiting its service life.

Thanks to the acetylation technology pioneered by Accsys Technologies, Accoya wood offers you an environmentally compatible, durable wood that can be used with confidence in outdoor applications and will last for many, many years.

Simply the Best

As ‘Class 1’ suggests, this is simply the best level of durability possible in wood. Whilst some wood species are naturally durable, natural durability is known to be a variable and inconsistent property.

Accoya wood, on the other hand, is consistently durable. The properties of every batch are analysed by standard scientific measurements after modification, enabling its durability to at least match and even exceed the performance of nature’s most durable species, including teak.

Additionally, durable woods tend to be slower growing species, whereas Accoya is made using fast growing, sustainably forested radiata pine, so old growth forests are not threatened or depleted to create Accoya.

Longer Lasting

Accoya wood’s durability makes it very long lasting, at least:

  • 50 years above ground
  • 25 years in-ground or freshwater contact

Accoya wood forms an effective barrier to insect attack; it is indigestible to microorganisms and insects and therefore more durable to wood-destroying fungi and virtually rot-proof.

Outstanding Durability
Insect Barrier

Where Durability Counts...

Heavy Traffic Road Bridge: "Several independent European research institutes tested Accoya’s suitability for this project. After rigorous testing, we found that its dimensional stability and incredible durability put it head and shoulders above other species and showed that it is suitable for laminating in large sections measuring 1080 x 1400 mm. Accoya is non-toxic and made from sustainably grown timber and these things were also considerations,” Sieds Hoitinga, Project Manager, Province of Friesland, the Netherlands.

Canal Lining: Certain environments are particularly punishing and few are harsher than canal banks where wood is used to hold back the earth, exposing it to water, microbe-rich soil and – most obviously at the waterline – air. Accoya offers unparalleled performance in this application, replacing tropical hardwood.

Decking: Applications like decking, where the wood is frequently wet and close to or in contact with the ground, demand a durable wood that is an effective mould and insect barrier. Acetylation has been shown to significantly improve performance against brown rot, white rot and soft rot. Accoya wood has also proven to be an effective barrier to wood destroying insect damage in multiple field tests and laboratory trails undertaken in many locations in the world. This includes tests with multiple species of termites.

Acetylation Process

Accoya is based upon acetylated wood technology, a process that has been studied by scientists around the world for more than 80 years.

This method of improving wood has been proven to deliver such superior performance that it has long been used as the "gold standard" against which other methods are measured.

Acetylation Process

The physical properties of any material are determined by its chemical structure. Wood contains an abundance of chemical groups called "free hydroxyls". Free hydroxyl groups absorb and release water according to changes in the climatic conditions to which the wood is exposed.

This is the main reason why wood swells and shrinks. It is also believed that the digestion of wood by enzymes initiates at the free hydroxyl sites - which is one of the principal reasons why wood is prone to decay.

Acetylation Process

Acetylation effectively changes the free hydroxyls within the wood into acetyl groups. This is done by reacting the wood with acetic anhydride, which comes from acetic acid (vinegar when in dilute form).

When the free hydroxyl group is transformed to an acetyl group, the ability of the wood to absorb water is greatly reduced, rendering the wood more dimensionally stable and extremely durable.

Acetylation Process

Acetyl groups are already naturally present in all wood species. This means that the manufacturing process adds nothing into the wood that does not already occur within it.

The end product, Accoya® wood, does not add toxins to the environment. The effect of altering the wood's chemical structure, as opposed to merely altering its chemical content, is to create an end product that is dramatically superior to its source species.

Acetylation Process

Accoya wood is modified right through the cross section whereas, by contrast, virtually all other treatments merely insert chemicals (such as oils, ammonia or metal compounds) into the wood, improving durability, to a degree, but not dimensional stability.

Accoya Academy

Accoya wood is the world's most durable, stable and sustainable timber ideal for windows, doors, cladding & decking and has a Minimum Service Life of 60 Year. See for yourself, why not learn more about Accoya, modified wood by Accsys Technologies.

Accoya Academy
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Accoya® Wood used for decking for private residence in Southern Italy

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James Latham

Available at www.lathamtimber.co.uk/contact-us