Accoya wood
Accoya® wood is a high performance wood which is more durable than teak, redwood or hardwood. It is sustainable, dimensionally stable and highly reliable. Accoya® has been developed to have performance properties that match or exceed those of the very best tropical hardwoods and is made only from fast growing, sustainably-sourced wood. It is non-toxic and, because it is so stable, it is easy to maintain which has both financial and significant environmental benefits. It also boasts superior resistance to the effects of UV exposure meaning that the natural appearance of the wood is retained for longer.
Preservation process
There are a number of different processes that can extend the life of wood. These aim to increase the durability and overall resistance of the wood to stop it being damaged by insects and fungus making it more resistant to decay. Accoya® wood has a number of patents pending relating specifically to its methods of preservation, which make its processes unique. However its technology is based on wood acetylation, a process that has been studied by scientists, globally, for around 80 years.
Wood contains chemical groups called "free hydroxyls". These absorb and discharge water according to the climatic circumstances to which the wood is exposed. This is one of the main causes of wood shrinking and swelling in size. It is also understood that the digestion of wood by enzymes begins at the free hydroxyl locations - which is one of the main reasons that wood is prone to decay.
Acetylation, in essence, changes the free hydroxyls within the wood into acetyl groups. This is done by creating a reaction between the wood and the acetic anhydride, which comes from acetic acid. When the free hydroxyl group is changed to an acetyl group, the ability of the wood to absorb water is significantly decreased, making the wood more stable and, because it is no longer digestible, much more durable.
Sustainability
By significantly enhancing the durability and dimensional stability of fast-growing and abundantly available certified wood, Accoya® wood provides compelling environmental advantages over slow-growing hardwoods (which are often unsustainably sourced), woods treated with toxic chemicals, and non-renewable carbon-intensive materials such as plastics, steel and concrete.
Accoya® wood is non-toxic, protecting the environment from poisons in treatments leaching into the earth. It may be safely reused and recycled and the manufacturing process adds nothing to the wood that does not already occur naturally within it. It has Class 1 durability making it the most durable wood possible. It also has a lower lifetime material consumption versus other materials. Accoya® wood has highly improved thermal insulation in comparison with commonly used wood species – this makes it ideal for applications where energy conservation is important.
Produced from abundantly available and fast-growing sources such as Radiata Pine Accoya® wood is created from sustainably sourced woods, including, FSC, PEFC and other regionally certified woods. It is an environmentally compatible substitute for carbon intensive materials. This helps to mitigate global warming. In addition it is fully reusable and recyclable and although reuse is recommended Accoya® wood may be safely incinerated for bio-energy or composted.
For all these reasons Accoya® wood is one of the very few building products to have acquired Cradle to CradleSM Gold Certification. For more information please refer to [www.c2ccertified.com]. Accoya® wood procedures are also assessed annually by an independent certification body to ensure that they meet FSC 1 and PEFC 2 Chain of Custody guidelines.
Accoya® projects
Accoya® wood is suitable for a wide range of exterior wood structures and has been used in a number of varying external applications including window frames, doors and shutters, cladding, siding, facades, decking and garden furniture. It has also been put to more imaginative use, such as in the building of traffic road bridges, the largest of which opened in the Netherlands in autumn 2008 to support two lanes of traffic across a 30 metre span which has a design life of 80 years. This formidable wood has also been used to create art structures, decking, boats, zoo fences, swimming pools and to contribute to the environmental credentials of energy efficient homes.
In May 2008, Accoya® wood featured on a live version of the popular Channel 4 program Grand Designs presented by British designer, writer and TV presenter Kevin McCloud. The challenge was to build a sustainable house in just one week, using traditional techniques and materials in conjunction with modern technology. Once completed the house was dismantled to be re-erected for display at the Building Research Establishment’s (BRE) Innovation Park in Watford.
Global accreditations
Accoya® wood is inspected several times each year by the notified certification body, SKH (Netherlands), within the KOMO® guidelines for modified wood, in accordance with assessment directive BRL 0605.
Accoya® wood has been tested in accordance with SKH publication 97-04 in respect to durability, dimensional stability, mechanical properties, workability, gluability and finishing, and has been shown to satisfy the requirements demanded of a wood species for use in KOMO® certified joinery and façade cladding.
Titan Wood, the company behind Accoya®, was certified by the Window and Door Manufacturers’ Association (WDMA) as a Hallmark Certified Supplier after meeting the requirements of the WDMA I.S.4 “Industry Specification for Preservative Treatment for Millwork” in October 2009. This rating certifies the quality of exterior millwork and gives government and private agencies a method of identifying windows and doors that are manufactured in accordance with the WDMA’s highest standards. The WDMA Hallmark® is a mark of excellence among architects, contractors and other specifiers. Products eligible for Hallmark certification are subjected to a rigorous verification process in order to ensure conformance with requirements.
Accoya® wood has been evaluated according to the VFF Merkblatt HO.06-4 for its suitability in RAL certified joinery. A provisional acceptance of Accoya® wood has been given in October 2009 and it has been added to the “approved” wood species list of the VFF (Joinery and Facades Association).