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The secret art to producing great parquet is to create gradings that are as uniform and dependable as possible. Because wood is a multifaceted natural product and every strip is unique.
Orientation thanks to the Grading Index
Every tree trunk, every wooden board and therefore every parquet strip is unique. In order to achieve the desired look for a parquet floor, Bauwerk assigns the individual strips to the so-called Grading Index based on wood characteristics. The Grading Index ranges from 1 to 6. Each one represents a wood characteristic like the "mirror" (= medullary rays), large and small knots, sapwood (= water–bearing capillaries) and various strengths of interplay of colours. Number 1 is very regular and uniform, number 6 stands for a characterful and lively look. Numbers 2, 3 and 4 represent the grading in between. Grading 13 means that all the wood characteristics from 1 to 3 can be included. A grading of 35, on the other hand, only contains the wood characteristics 3 to 5.
The basic rule is that the smaller the number, the less variation there is in the grading, the bigger it is, the more rustic it will look (12/13 = very calm, 14/23 = calm, 15/24/34/23/35 = lively, 45/46 = rustic)