Alternatives to preservative impregnation are emphasized in Germany and other European countries. Even though these treatments significantly improve wood's resistance to decay, they often do not have a beneficial impact on the dimensional stability. One alternative product, which may be used in ground contact for items like poles and railway sleepers, could be beech (Fagus sylvatica L.) laminated veneer lumber (LVL) impregnated with low-molecular phenol-formaldehyde (PF). PF resins are often used for bonding and impregnation purposes. In this research, low-molecular weight PF was used, which allows a penetration and fixation within the cell wall. Various PF-resins were used to impregnate beech veneers and LVL was manufactured with a variety of process parameters. In ground durability tests started in 2015 and were evaluated based on EN 252 (2015) on the test field at the University of Goettingen; Germany as well as in Stamsmåla, Sweden. The durability classes (DC) were determined based on the decay rates. The evaluation showed that very durable products for in ground contact can be produced from beech wood, but durability clearly depended on the resin type and loading.

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