Accoya® is wood, but not as you know it. It is modified timber in which a process called acetylation, a cutting-edge patented technology, enables it to resist rot, defy the elements and stay strong for decades. Guaranteed for 50 years above ground and 25 years in ground or freshwater, its performance and properties are remarkable. From joinery for the home to bridges submerged in water, Accoya® long life wood is a leading material that stands up to every application challenge – decking, wood cladding and more.


Due to its improved properties – such as increased durability, improved thermal insulation and longer coating life as a result of increased dimensional stability – Accoya® wood provides several environmental gains during its use phase. This makes Accoya® a good option for those wanting to use sustainable building materials.

First, the durability of Accoya is Class 1 (EN 350), the highest durability class possible, has extensive quality certifications (KOMO, RAL, BBA, WDMA, etc.) and is guaranteed to last 50 years above ground and 25 years in direct soil contact. This facilitates a longer lifespan which enables lower material consumption (less replacement!) over the same period compared to most other materials. This also means that Accoya has carbon sequestration advantages as it locks CO2 for a longer time from the atmosphere. In fact, because of low emissions during production combined with the increased life span and good recyclability, Accoya window frames are even assessed to be CO2 neutral over the full life cycle, for more information see environmental assessments

Furthermore, the superior dimensional stability of Accoya means it requires less frequent coatings maintenance with the subsequent environmental benefit (and lower costs as well). Combined with the increased durability this means that the planned Service Life of Accoya (77 to 90 years, depending on exposure conditions) is superior to regular timber.

Finally, compared to other durable wood species, Accoya offers superior thermal insulation, which yields energy conservation advantages in applications such as window frames.

Accoya wood products have an incredible amount of green benefits –

  • Highly durable, guaranteed for 50-years above-ground, 25-years in-ground
  • Dimensionally stable, reducing shrink and swell by 70-80%
  • Requires minimal maintenance including coatings life
  • Easy to machine, glue and coat
  • Reduced cupping, bowing, twisting, or cracking
  • Indigestible to insects
  • Sustainably sourced from FSC certified and other well managed forests
  • Retains strength and increased hardness
  • Non-toxic

Sustainability credentials:

  • Cradle to Cradle Certified Gold
  • Cradle to Cradle Product Innovation Institute’s Material Health Certification (Platinum Standard)
  • Google’s Healthy Materials Program, Portico – 15 out of 16 points
  • ICC-ES Report ESR-2825 verifies that Accoya wood meets code requirement – approval for applications above-ground or ground-contact requiring protection against fungal decay or termites as described by the code.
  • Declare Label by the International Living Future Institute, Red List Free
  • LEED v4


As outlined in the various sections, in every stage of the life cycle Accoya provides compelling environmental advantages. As they value transparency at Accsys, all claims about our sustainable timber are always referenced to recognized standards. Therefore, the environmental performance of Accoya® is thoroughly tested and published following uncompromising leading independent international methodologies such as Life Cycle Analysis (LCA following ISO 14040/44) and Environmental Product Declarations (EPD following ISO 14025 and EN 15804). Besides this they seek to acquire the most respected ecolabels worldwide.

Visit Accoya to learn more about their eco-friendly modifies wood products.