Our quality grading
Main thickness 27 mm
We have established quality standards for grading our sawn timber in 160+ wide derived from European standardsNF EN 975-1using the symbol "QF" for the Q of Quercus (the oak) and F for the Freezes and square edged oak.
The attached photos are just a starting point for explanation.
We distinguish qualities according to two main families:
Grading on both reference faces
QF1AQF1A/1b QF1b/2 QF2/3
Each board is inspected on both sides to ensure a selection of compliant knots. Particular attention is paid to the flatness of the board, as it is often intended to be re-sawn to thickness.
Grading on one reference face
QF1-2X QF2/3X QF3/4x KERN QF5X
Indicated by the letter X meaning that on the underside there may be limited presence of sapwood but not necessarily on all boards. In the lower choices, a trace of closed heart is accepted.
Depending on the widths and the grading programme, we also have grading variants. Here is a table for informational purposes.
QF norm | Usual | Description |
QF1Q | 1Q | 1st choice quarter and rift sawn |
QF1A | 1 | 1st choice |
| QF1A/1b | 1/bis | 1st/bis = Blend of 1st choice and bis knots 12 mm |
QF1b | Bis | Some small knots 12-15 mm |
QF1b/2 | Bis/2 | Healthy knots |
QF2/3 | 2/3 | Knots from 25 to 50 mm |
QF1X | 1X | 1st choice/ Bis with sapwood tolerated on the back face |
QF1-2X | 12X | Select |
QF2/3X | 2/3X | Rustic A - knots up to 50 mm |
QF3/4X | 3/4X | Rustic B - knots 45-80 mm |
QF4/5C | Kern | Heart 2 faces |
QF5X | 5X | Large knots up to 12 cm. No pinholes. No brown oak. |
Download ourQuality Sheet (pdf English)
QF 1b/2
Healthy knots 12-25 mm
QF 2/3
Knots 25-45 mm
QF 3/4X
Knots 45-80 mm
KERN
Heart 2 faces
