classes of use for acacia wood
When choosing a wood specie, several criteria must be respected according to the according usage. The first criteria is the class of employment. The class of employment or risk class is established by the European standard EN 335-2013. This European Standard defines five risk classes that correspond to the different situations in which wood may be exposed. These classes are summarized in the table below:
According to the European standard, acacia wood is the only European specie suitable for uses in risk class 4 "Outdoor use in contact with soil and fresh water, exposed permanently to moisture" just as the tropical species such as iroko, Ipe. Nevertheless, these tropical woods arrive in Europe after thousands of kilometers, which has a harsh impact on the carbon footprint. In addition, the management of some of these forests is not always respected. At the European level, two species try to compete with acacia wood, there are oak and chestnut. However, these two species are classified in class of risk 3, they can be used outside but without contact with soil and permanent humidity.
In terms of natural wood durability, acacia wood is ranked, according to European standard EN 350-2, in the 1st class with a durability way longer than 25 years such as Moabi, Teak or Ipe (see the table below).
Oak and chestnut are classified in the 2nd class which have a durability of 15 to 20 years.