Nordic wood processing with quality to be proud of
The Nordic Wood Preservation Council (NWPC) publishes an industry standard for wood protection classes that is in line with the European standard for ranking and assessing the durability of wood products and its treatment or modification.
Over the years, the Nordic Wood Preservation Council and the Swedish Wood Preserving Institute, together with Swedish and Nordic research institutes and Universities, have had a significant influence on the development of standards in the field of wood preservation in Europe and the world.
The wood protection classes according to the NTR-system are coordinated with the European standards EN 351-1 and EN 599 which the whole of Europe follows. However, the NTR-system goes several steps further by specifying User Class and Penetration as well as a number of very concrete rules to achieve good durability and high and consistent quality.
The NTR wood quality system is far-sighted and includes all wood materials and new technologies. With this, modified wood products such as, heat-treated wood, silica-treated wood, linseed oil-treated and more can compete on equal terms. Customers and specifiers receive correct, factual and comparable documentation of the durability of wood products.
For a producer of durability modified wood, it is easy to connect a new product or process to the NTR wood quality system and the cost of participating is small in relation to the producer’s other costs for development and marketing. The real challenge is to prove the new wood product is durable and has a robust quality in industrial manufacturing. The rigorous approval tests takes up to 5 years to carry out in field tests and trials to assess a wood product’s resistance to rot and more. Products that have passed the test have the right to label the product with NTR-mark.
The NTR brand is a guarantee of a long service life, durability and quality.
The requirements for durability and quality are high in the EN standard and even higher in the NTR system, which means that only products with improved durability pass the tests and receive labelling rights according to NTR. The wood protection classes in NTR wood quality system and the European standard are designed to provide a significantly improved durability compared to untreated wood.
Responsible specifiers and buyers
The customer / buyer must take his responsibility as he has a key role and must be familiar with wood sorting and durability classification in order to be able to independently verify product documents and test reports if you intend to choose other than NTR-classified wood. Many non-approved products present test certificates that are irrelevant to assess durability and economic life. Require relevant documentation! The NTR system helps the buyer to make a fact-based decision.
The most common wood protection classes for consumers and construction are NTR A, NTR AB and NTR Gran.