Various procedures are used for testing the durability of wood and wood based materials for decades. Generally they can be divided in field and laboratory tests, whereby lab tests allow more defined and reproducible conditions and benefit from shorter test durations. However, while laboratory test results are hardly transferable to real life situations, field tests ensure more realistic conditions. For instance natural weathering and detoxification of biocidal compounds through so called “non-target-organisms” is assured only under outdoor field exposure. Due to these dissimilarities a diverse and in some cases also unrealistic classification of wood durability can be obtained when testing a material exclusively under laboratory conditions.