Grading floors A&D Houtbewerking
Prime
- Knots: none, but pit knots not allowed
- Sap wood and head cracks: not allowed
- Colour difference: not allowed
- Water stains: not allowed

1-Bis
- Knots: maximum 18 mm
- Sap wood and head cracks: not allowed
- Colour difference: little allowed
- Water stains: not allowed

Rustic A
- Knots: maximum 35 mm
- Sap wood and head cracks: not allowed
- Colour difference: little allowed
- Water stains: not allowed

Rustic AB
- Knots: Maximum 70 mm
- Sap wood and head cracks: little allowed
- Colour difference: allowed
- Water stains: allowed

Rustic C
- Knots: allowed
- Sap wood and head cracks: allowed
- Colour difference: allowed
- Water stains: allowed
