OAK Natur
Character: It features some bigger knots, and rather dynamic colors and graining but without harsh color variations, with lamellas having some tint variation. Only minor flame pattern is permitted. Knot: Healthy, well intergrown knots in sizes of up to 15 mm Ø, and black knots in sizes of up to 5 mm Ø are permitted, also in groups. Sapwood: Fundamentally, it is not permitted, but healthy tangential sapwood, up to 3 – 4 mm in width and 5 – 10 cm in length, is permissible.
OAK Rustic
Character: It is characterized by the sapwood and the knots, as well as its prominent textural and color variations. Flame pattern is permitted. Knot: Healthy, well intergrown knots in sizes of up to 15 mm Ø, and black knots in sizes of up to 5 mm Ø are permitted, also in groups. Sapwood: Healthy sapwood is permitted up to about the 1/3 of the lamella width.
ASH Natur
Character: Its color is defined by the natural growth of the tree – with darker and lighter slats. Without any particularly striking, harsh textural and color variations. Knot: Healthy knots up to a diameter of 3 mm, and dark knots up to a diameter of 1 mm are permitted, except for those in groups. Red heartwood: Not permitted.
ASH Rustic
Character: It is characterized by accentuated colors, particularly the red heartwood, and the knots and a vivid texture. Knot: A healthy knot, up to a diameter of 10 mm, is permitted. Red heartwood: Dark tone and red heartwood is permitted even across the whole width of an individual slat.
According to the EN 13489 standard, 3 % of different grade than indicated is acceptable.