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DURABLE, STABLE
& SUSTAINABLE

INNOVATION
IN WOOD

The possibilities wood offers can be seen wherever we look: as furniture, decoration, musical instruments, structures – wood is a material that is aesthetically pleasing, endlessly practical and is our only naturally renewable building material. However, as an organic material that is susceptible to its surroundings, wood presents natural challenges when used for certain exterior applications. 

Historically, the only way to overcome these challenges was to treat the wood with preservative chemicals or to choose tropical hardwoods from rapidly diminishing forests – offering only partial solutions to the natural challenges that are faced when using wood as a building material. 

If an alternative existed which offered all of the best characteristics of wood, was sourced from sustainable forests, had zero toxicity and provided dimensional stability and durability that matched or exceeded even the best tropical hardwoods, an ideal material would have been found.

Accoya® wood is the solution.

IDEAL FOR WINDOWS,
DOORS, CLADDING AND MORE

Accoya® wood is the result of decades of research and development that has brought together a long-established and extensively proven wood modification technique – acetylation – and leading-edge patented technology to create a high performance wood, ideal for outdoor use and challenging applications.

Accoya® wood has properties that match or exceed those of the best tropical hardwoods, yet is manufactured from sustainable sourced wood.

Already the material of choice for a wide range of demanding outdoor applications, Accoya® wood can be used for virtually anything from windows to doors, decking to cladding, bridges to boats and even for
applications that are presently only feasible with nonsustainable and man-made materials.

Accoya® is the future of wood.

ENABLING
NATURE WITH
HIGH TECHNOLOGY

Accoya® wood is modified all the way through, not just at the surface like traditional envelope treatments. This modification technique has two key advantages:

Using an array of sophisticated and proven analytical techniques, the producers of Accoya® wood ensure that every batch is of consistent quality and reaches the highest possible level in durability and dimensional stability versus the unpredictability of other choices.

When Accoya® wood is cut or jointed there are no exposed nonacetylated surfaces in any dimension. This completely negates the need to apply additional chemical preservatives on-site, as is necessary with unmodified or envelope-treated woods.

KEY
FEATURES 

Accoya® wood is produced from sustainably sourced, fast growing wood and manufactured using Accsys’ proprietary patented modification
process from surface to core.

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 even teak
  • Virtually rot proof
  • 70 year minimum service life stated by TRADA
PERFECT FOR COATING
  • Improved stability means coatings last up to two times longer
  • Easier to coat, less preparation and sanding required
BAREFOOT FRIENDLY
  • Low thermal gain
  • Barefoot Friendly
  • Ideal for all decking situations in extreme temperatures
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
CONSISTANT 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

ENABLING NATURE NATURALLY

Wood acetylation is 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. The
Accoya® wood patented production process combines this work with years
of proprietary research and investment to deliver consistent results on a
commercial scale.

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 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.
Enabling nature

NATURAL SCIENCE

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 naturally 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. 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.
Natural Science

ACETYLATED L-JOINTS OUTPERFORM ASA AND UNTREATED L-JOINTS AFTER 15 YEARS* 

The BRE (Building Research Establishment) is an independent institute based in Watford, UK. In durability field testing to European Norm (EN) 330:1993 – which parallels America Wood-Preservers’ Association (AWPA) E9 – simple mortice and tenon joints (L-joints) are assembled, coated and placed outside, with the coating over the joint deliberately broken to allow typical water ingress. This test represents a worst case scenario for joinery
products and requires the coated wood to be exposed to normal environmental factors.

In February 1998, L-joints were installed at the BRE Garston field exposure site (Watford, UK) facing the prevailing south westerly weather on an elevated test rig. The test remains in progress with inspections at regular intervals. The durability class 1 acetylated wood condition is unchanged and continues to look good, while the unmodified wood has degraded completely after 7 years of exposure.

The BRE reported: “In simulated accelerated joinery field trials that represent a worst case scenario joinery product by enabling moisture ingress into the joint pine, sapwood wood L-joints acetylated to a slightly lower modification level than Accoya, after 15 years exposure in the UK are performing very well.”

EXCELLENT COATINGS PERFORMANCE TESTED BY BM TRADA

The translucent stain finish was seen to have remained fully intact over the 42 month outdoor exposure period on all the boards with no visible failures in evidence apart from where the coating had been broken by an end-fissuring. No evidence of any peeling of the stain coating was seen along fissures where they occurred. No evidence of mould colonisation was observed on any of the boards. Other competing cladding material coatings failed in the same tests with severe issues.

LONGER LASTING COATINGS

Accoya® wood is the ultimate substrate, and its lower maintenance requirements add to its cost effectiveness and environmental credentials. Coatings may be transparent, translucent or opaque, allowing for more adventurous colour schemes that will endure.

All major coatings systems can be used on Accoya® wood, with significantly improved performance, due to the wood’s outstanding dimensional stability and resistance to UV degradation. Extensive tests have shown that the natural beauty of Accoya® wood lasts longer, even in the most severe weather conditions.

TRIED AND TESTED

Extensive laboratory and field testing by leading institutes around the world (including in New Zealand, USA, UK, Sweden, Malaysia, Indonesia, Russia, the Netherlands, Germany and Japan) has shown the performance of acetylated wood to be extremely reliable. 

Accoya® wood has been thoroughly tested for performance characteristics such as 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 modification techniques are measured.

NATURALLY BEAUTIFUL WOOD 

Accoya wood retains its natural colour after acetylation demonstrating that the natural beauty of the wood lasts longer in exposed conditions. This, coupled with Accoya® wood’s improved dimensional stability and excellent thermal properties, means that wooden windows, doors and cladding/siding can once again compete effectively with artificial alternatives.

OUTSTANDING DURABILITY

Accoya® wood’s durability is Class 1, matching and even exceeding the performance of nature’s most durable woods. Scion, formerly known as the New Zealand Forest Research Institute, has published a report which concludes that Accoya® wood is more durable than four of the most naturally durable species. After six years of exposure in accelerated decay chambers and exterior ground contact tests, Accoya® wood was in much better condition than the cypress, cedar, kwila and teak when tested to the same rigorous standards. Radiata pine with copper chrome arsenate (CCA) treatment to the H3.2 and H4 New Zealand industry specifications for ground contact was also notably outperformed by Accoya® wood.
Outstanding durability

DIMENSIONALLY STABLE

Accoya® wood offers dimensional stability (resistance to swelling and shrinkage) in both radial and tangential directions. Tests have shown up to 80% reduction in swelling caused by moisture uptake, depending on the source species and conditions. From oven dry to water saturated conditions, the swelling and shrinkage of acetylated wood is only minimal and, in fact, better than tropical hardwoods. Dimensional variability resulting from thermal changes (ambient or radiant temperature variations) is, like most woods, minimal.

THIS IS THE FUTURE OF WOOD...

Accoya® wood has been tested over prolonged periods in all types of weathering conditions – above ground, below ground and even in water – and has been proven to withstand even the toughest of external environments. Not only is its durability proven, but it has also been shown to retain its appearance, requiring much less frequent maintenance than other wood species. This gives added reassurance to the manufacturers, architects, specifiers, builders and property owners who have chosen Accoya® wood for a diverse range of projects. Accoya® wood is also being tested for additional uses by leading independent institutes worldwide.

WINDOW FRAMES, DOORS & SHUTTERS

Accoya® wood is the material of choice for these products as it has low thermal conductivity and is more durable and more dimensionally stable than the best tropical hardwoods. It may be finished with opaque coatings, or for those who enjoy the natural beauty of wood, finished with transparent coatings. Accoya® wood’s low maintenance requirements add to its cost effectiveness and environmental credentials.

PORCH AND EXTERIOR FLOORING

Accoya® allows solid wood flooring in environments previously unthinkable such as wet areas and over-radiant heating without risk of excessive distortion. 

OUTDOOR FURNITURE & EQUIPMENT

Accoya® wood is perfectly suited to tables, chairs, play frames, planters and landscaping timbers as it is non-toxic and able to withstand the rigors of different weather conditions.

CLADDING, SIDING & FAÇADES

Accoya® wood is suitable for cladding, siding and façades where aesthetics, less frequent maintenance, dimensional stability and durability are key factors. Accoya® gives a wide range of coatings choices for unprecedented choice without compromising performance.

DECKING & MARINAS

In specifying decking, jetties and pontoons, beauty, strength and all-weather performance are important. A material that will not cup, bow, warp, split, swell or be affected by fungi, water uptake or rot is desirable. It is also crucial that the wood is non-toxic and therefore totally safe for people and animals. Accoya® meets these requirements, even in salt water splash zones. 

BRIDGES & CIVIL WORKS

With its high strength to weight ratio and overall superior performance, Accoya® allows wood to be used in demanding applications such as heavy traffic road bridges. 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® wood offers unparalleled performance in this application, replacing tropical hardwood.

...THIS IS ACCOYA

By significantly enhancing the durability and dimensional stability of fast-growing and abundantly available certified wood species, Accoya® wood provides compelling environmental advantages over slow-growing hardwoods (which are often unsustainably sourced), woods treated with toxic preservative chemicals, and non-renewable carbon-intensive materials such as plastics, steel and concrete. 

  • The Accoya® wood patented modification process adds nothing to the wood that does not already naturally occur in it
  • Class 1 durability - facilitating a longer lifespan, improved carbon sequestration potential and lower lifetime material consumption versus
  • other materials
  • Outstanding dimensional stability, resulting in lower maintenance frequency and therefore less coating over the lifetime of the product
  • Superior thermal insulation, providing energy conservation advantages when used for applications such as windows and doors
  • All Accoya® wood is produced from well managed sustainable sources including FSC® and other regionally certified woods
  • Low carbon footprint: Accoya® wood is an environmentally compatible substitute for carbon intensive materials
  • Environmentally compatible: 100% recyclable and reusable, naturally renewable
  • Rapidly renewable materials: use of abundantly available and fast-growing source species
Accoya

IMAGINATION UNLIMITED

Accoya® wood is already being used for many new and exciting applications. It opens up all kinds of creative possibilities and is inspiring architects and designers to look at new and different ways of using wood instead of manmade products, safe in the knowledge that their creations will be sustainable and long lasting. Wherever you can imagine wood, imagine Accoya® wood. 
Imagination unlimited

ACCOYA® ACCREDITATIONS

Accoya accreditations
C2C

Accoya® wood is one of the very few building products to have acquired Cradle to Cradle SM Certification on the elusive C2C Gold Level.
Cradle to Cradle (C2C) provides a means to tangibly and credibly measure achievement in environmentally-intelligent design including the use of environmentally safe and healthy materials and instituting strategies for social responsibility.

FSC
FSC

Of the various schemes for sustainable forestry available, the Forest Stewardship Council (FSC®) is regarded as the leading and most comprehensive certification program available. This program not only focus on benign environmental performance but also safeguard social interests for all stakeholders involved.

FINGER JOINTED ACCOYA FOR JOINERY
SPECIFICATION SHEET

KEY FEATURES

Accoya® wood is produced from sustainably sourced, fast growing wood and manufactured using Accsys’ proprietary patented modification process from surface to core.

DIMENSIONALLY STABLE
OUTSTANDING DURABILITY 
PERFECT FOR COATING
BAREFOOT FRIENDLY
NATURALLY INSULATING* 
EXCELLENT MACHINABILITY
INSECT BARRIER
CONSISTANT QUALITY THROUGHOUT 
NATURALLY BEAUTIFUL WOOD
FROM SUSTAINABLE SOURCES
RETAINED STRENGTH & HARDNESS
NON-TOXIC & RECYCLABLE 

ACCOYA FINGER JOINTED SPECIFICATION

Accoya® finger jointed is bonded with EPI adhesive. It offers fixed width, engineered sections for joinery under the KOMO joinery certificate for finger joint quality. Accoya® has been finger jointed under the KOMO scheme successfully since 2007, predominantly for the Dutch market. NOTE: Finger joints are rated for use as joinery and not in-ground.

Finger joint quality certification for opaque joinery use:

UK AND EIRE JOINERY CERTIFICATION SCHEME 

Accsys Technologies declares that Kerrydean Ltd has successfully completed a training programme and are entitled to consider themselves ‘Trained users of Accoya®’ and, as such, can market themselves accordingly,

Date of issue 29th September 2014 - Click here to view our certificate

Issued to Kerrydean Ltd

Declared by

Accsys Technologies
Brettenham House
19 Lancaster Place
London
WC2E 7EN

Rob Harris
Chief Executive Officer
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