Oak Grades Explained: From QF/1a to QF/5
Updated: 3 days ago
Two quotes for oak planks, a twenty percent price difference, and both state "first choice". Anyone who regularly purchases oak knows that moment. Without a shared language for quality, you are comparing apples and oranges. That language does exist: EN 975-1. As soon as you speak it, purchasing becomes much clearer.
Why oak is sorted
A hundred-and-twenty-year-old oak has seen its fair share of things. Branches that died off and became overgrown, a harsh winter that tore a crack, a year with so much growth that the grain ripples. All of that is in the wood and comes to the surface when sawn. No two planks are alike.
Sorting is therefore not about good or bad wood, but about predictability. A sorting establishes which characteristics occur to what extent, so that you know what is coming off the truck. Importantly: a sorting describes the average appearance of a batch, not every plank individually. A single section that turns out to be larger does not determine the class.
Squared oak: QF/1a to QF/4
Squared oak — called 'bekantrecht' in Flanders and in part of the Dutch trade — is sawn timber with sharp edges up to 100 mm thick. Sawn to a fixed width and bundled by width, it is called 'avivés' in the French trade: from 100 to 400 mm wide, in lengths up to 500 cm. The grades range from strict to generous, and the difference lies almost entirely in the knots.
QF/1a — defect-free. Straight-grained wood with an almost closed appearance. For sections narrower than 120 mm, one sound knot up to 10 mm is permitted; for wider sections, two. The yield per log is low, and this is reflected in the price.
QF/1b — practically defect-free. Three sound knots up to 12 mm for parts under 120 mm wide, plus one additional knot per 40 mm of extra width. Knots smaller than 5 mm do not count. For many customers, this is the commercial optimum.
QF/2 — lightly rustic. Three knots up to 25 mm, again with an extra knot per 40 mm of width. This is the image most people have in mind for oak, and by far the most requested grade for furniture and interior work.
QF/3 — rustic. Knots up to 40 mm and one dead knot up to 20 mm. Pronounced character, but without the annoying defects: no bark inclusions, no brown core, no rot, no cut pith.
QF/4 — extra rustic. Sound knots up to 70 mm without quantity limit, two dead knots, and wane of up to 10% of the width. Popular for floors and tabletops with a country look. Rot and through holes are excluded here as well.
And then there is QF/5
If you look up QF/5 in EN 975-1, you will find nothing. This class is not listed in the standard — the market invented it itself for everything that does not fit into categories 1 through 4. Production remnants, batches with a non-standard characteristic, and timber that the sawmill sorts according to its own description. That does not make it any less usable; there are often competitively priced batches among them that are perfectly suitable for the right application.
However, one rule applies more strictly here than elsewhere: because there is no underlying standard, you have nothing to fall back on in the event of disagreement. With QF/5, the written description is the only agreement you have. Therefore, always ask for a bundle sample and a description on the order confirmation before calling off.
The X and the XX: sapwood
An X or XX may appear after each squared class. An X means that healthy sapwood is permitted on one visible side over less than two-thirds of the thickness; XX applies to both sides. If nothing is stated, a good dealer supplies sapwood-free material — and charges accordingly. If you ask for QF/2 when you mean QF/2 X, you are paying unnecessarily for stricter sorting. The reverse, incidentally, occurs more frequently, and you only notice this when unpacking.
Timber beams : appearance and load-bearing capacity in one code
With timber beams, there is an additional factor that plays no role with planks: strength. For load-bearing applications, CE marking is mandatory, and the load-bearing capacity is determined by visual strength grading according to the French standard NF B 52-001. That sounds like a second layer of paperwork, but it is not that bad.
For beams thicker than 100 mm, there is a fixed link between appearance class and strength class. QP/A corresponds to D30, QP/1 to D24, and QP/2 to D18. Therefore, a single designation on your order determines both the appearance and the structural value. QP/A is fully sharp-edged visible timber, QP/1 is the working beam for most roof structures, and QP/2 is the robust timber with wane and heavy knots for garden work and canopies.
Unedged and sheet wood : QB and QS
If you purchase unedged, with wane edges and bark, QB applies to closed logs and QS to selected loose sections, both from A to 4. Those who do the division themselves achieve the highest yield and the widest sections here.
Note one rule here that surprises many buyers. A log is sorted as a whole, and the standard allows for some leeway: at least 65% of the volume falls into the specified class, less than 25% may be one class lower, and less than 10% two classes lower. For selected individual parts, the bar is set higher — there, at most 10% may fall below the lowest specified class.
What you gain from this
Three things make your next purchase measurably better. Always state the grade *and* the sapwood designation, so QF/2 X instead of "first choice". For board timber, explicitly ask about the distribution within the log, because that is where the difference lies between two quotes that look identical on paper. And ask for a bundle sample before ordering — a good supplier will send this free of charge, or have a selection ready for you on site.
We sort entirely according to EN 975-1 and NF B 52-001 and do not use our own house codes. Therefore, you order from us using the same designations as from a French sawmill, and can compare quotes side by side without translation. Are you unsure between two sorting options? Contact us — and we will compare them.
All seventeen sorting grades are listed with photos and limit values in our quality guide. Download it here as a PDF (22 pages) — no form, no email address required.
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