Sustainable construction means longevity, through using wood material with the longest possible life cycle. For pressure-impregnated wood, requirements for certification should be applied in accordance with the Nordiska Träskyddsrådet (NTR) regulations: the treated wood must meet the wood treatment classes NTR AB, NTR ABmod, NTR A and NTR Amod, depending on the intended area of use.
A wood product that has been prepared in accordance with the Nordiska Träskyddsrådet (NTR) regulations and which is NTR labelled has a technical service life of 25 to 30 years, depending on area of use and level of maintenance. The actual service life will almost certainly be longer than the technical service life; depending on the prevailing conditions and the structure, service lives in excess of 50 years are not uncommon.
Wood products in NTR A class (in contact with the soil – fence posts, for example) have an expected service life of 20 years, compared to the service life of untreated wood in soil, which is just four years. So, the service life of treated wood products is five times that of untreated wood. NTR-certified wood products provide the lowest life-cycle costs in comparison with other construction materials.
