LONDON – Accsys Technologies now offers North American species red alder as part of its line of modified-wood products. Like the original, award-winning Accoya wood, Accoya Alder undergoes a proprietary modification process called acetylation that improves its durability, hardness, water absorption, and dimensional stability while retaining its natural strength and beauty.

Alder boasts a fine grain and a medium tone—a clean, attractive look popular for construction of interior doors, cabinetry, flooring, and moldings. By applying the patented acetylation technology, Accsys Technologies has expanded the opportunities for alder to exterior applications, including screens, outdoor furniture, windows, and exterior doors, while still maintaining the species’ aesthetic qualities.

Accoya wood’s acetylation technology alters the wood’s reaction with water by permanently replacing the molecules that want to bond with water with more stable acetyl groups. Acetyl groups are naturally present in all wood species, which means that nothing toxic is added. The altered cell structure of the wood makes it an unrecognizable wood source for insects and prevents fungal decay.

Though the acetylation process has been studied by scientists for more than 75 years, Accsys Technologies was the first company to make the technology commercially successful, using radiata pine. Alder has been introduced after several years of R&D, material testing, and prototype trials, including doors, windows, flooring, and outdoor furniture. Accoya Alder offers the same performance properties as original Accoya radiata pine, including a European durability class 1 rating of EN 113:199 in use classes 1-4, 80% improvement in dimensional stability, and a30% higher Janka hardness than the pre-modified wood.

“Since its introduction, Accoya wood has been widely used on the exteriors of innovative residential, commercial, and government projects around the world, providing a stunning visual effect along with the durability to withstand even the harshest environments,” said John Alexander, head of product developmentat Accsys Technologies. “The addition of Alder expands specifiers’ design options for the exterior while retaining long-term performance benefits.”

David Venables, European director of the American Hardwood Export Council said, “The launch of Accoya Alder is a very exciting development for the wood trade. American hardwoods are highly available and increasingly fashionable for interior applications. The improved durability provided by the wood modification process enhances exterior performance and gives specifiers a wider choice of natural sustainable and high-performing products. This is a validation of the opportunities for American hardwoods in the field of wood modification, and we are keen to see continued innovation and application of this technology on American hardwoods.”

The Accoya product line carries a 50-year above-ground and 25-year below-ground warranty against rot and decay. The wood is sourced from FSC- and PEFC-certified forests and has achieved Cradle to Cradle Gold certification.

Accoya Alder will be available throughout North America, Europe, Asia, and many other parts of the world through our network of Accoya wood distributors. For more information about Accoya Alder, please visit

Source: Accsys Technologies

Have something to say? Share your thoughts with us in the comments below.