Efficacy of linseed- and tung-oil-treated wood against wood-decay fungi and water uptake

Most European wood species do not have durable wood. In order to be used in outdoor conditions, non-durable material must be protected. Non-biocidal solutions for wood protection have been attracting a lot of attention, particularly in class 2 and 3 applications. One non-biocidal technique is treatment of wood with water repellents, such as wax emulsions and oils. Linseed oil and tung oil are frequently used water repellents. This research reports on the performance of linseed- and tung-oil-treated Norway spruce and beech wood against wood-decay fungi. Additionally, short-term hydrophobic properties were determined (with a tensiometer), as well as long-term hydrophobic properties (by soaking in water) in laboratory and outdoor conditions (electrical resistance measurements). Wood treated with tung oil and linseed oil is protected against brown- and white-rot fungi; however, tung oil was found more effective. Not only did the oils tested prove efficacious against wood-decay fungi, but also they worked against short-, medium-, and long-term water uptake as well. Oil treated wood takes up less water during laboratory tests, as well as during outdoor testing.