Influence of top layer density and thickness on hardness of two-layer floor elements

The subject of this paper is testing the hardness of two-layer floor materials with top layer made of ash wood in tangential cut, and bottom layer made of pine wood, radial cut, with cross wood fibre layout in both layers. Tests were carried out for top layer thickness 6.6 mm, 4.0 mm and 2.0 mm. Strong correlations were noticed between the hardness of floor elements and the density of the top layer for each thickness variant. Overall statistically significant influence of bottom layer density on the hardness of two-layer floor elements was observed in samples whose top layer was 2.0 mm thick.