Skip to Content

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
no knots

QF1A/1b1/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
12-25 mm

QF2/3

2/3

Knots from 25 to 50 mm
No sapwood, no heart, no edge knots.

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
Flat wood

QF5X

5X

Large knots up to 12 cm. No pinholes. No brown oak.


Chêne en qualité 2 ou QF1b/2

QF 1b/2

Healthy knots 12-25 mm

Chêne en qualité 3 ou QF2/3

QF 2/3

Knots 25-45 mm

Chêne en qualité 4 ou QF3/4X

QF 3/4X

Knots 45-80 mm

Chêne Kern

KERN

Heart 2 faces