Accoya wood's durability is Class 1, matching and even exceeding the performance of nature's most durable woods. Durability is assessed by measuring weight loss over time in exposed conditions. Acetylation has been shown to improve resistance to brown rot, white rot and soft rot significantly, with the percentage reduction in original mass being negligible compared to unmodified wood.
One of Accoya wood's main advantages is that its key properties can be analysed by standardised scientific measurements after modification, enabling its durability to be guaranteed.
Accoya wood has superior resistance to UV degradation, with extensive tests demonstrating that the natural beauty of wood lasts longer in exposed conditions.
| Wood Species | Durability/Class* (1=highest) | Janka Hardness Newton** | Radial & Tangenital swelling between 60-90% RH | Tangenital Shrinkage between 60-90% RH |
|---|---|---|---|---|
| Accoya® | 1 | 3950 | 0.4 | 0.7 |
| Scots Pine | 4 | 2900 | 1.0 | 2.4 |
| Western Red Cedar | 2 to 3 | 1450 | 0.5 | 1.2 |
| Dark Red Meranti | 2 to 3 | 4300 | 0.9 | 1.8 |
Comparison of the Technical specifications of different wood species and Accoya®.
* Based on classification by EN350. Durability class 1 corresponds to a 60 year service life in applications such as windows, doors, balconies and cladding in the British Standard BS 8417.
** Janka hardness and bending strengths are based on wood conditioned at 65% RH and 20°C. Values for all values are heavily influenced by local growth conditions.